ÿþ<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:st1="urn:schemas-microsoft-com:office:smarttags" xmlns="http://www.w3.org/TR/REC-html40"> <head> <meta http-equiv=Content-Type content="text/html; charset=unicode"> <meta name=ProgId content=Word.Document> <meta name=Generator content="Microsoft Word 11"> <meta name=Originator content="Microsoft Word 11"> <link rel=File-List href="DC_elevation_metadata_files/filelist.xml"> <link rel=Edit-Time-Data href="DC_elevation_metadata_files/editdata.mso"> <!--[if !mso]> <style> v\:* {behavior:url(#default#VML);} o\:* {behavior:url(#default#VML);} w\:* {behavior:url(#default#VML);} .shape {behavior:url(#default#VML);} </style> <![endif]--> <title>District of Columbia Elevation Data underlying analysis by J</title> <o:SmartTagType namespaceuri="urn:schemas-microsoft-com:office:smarttags" name="Street"/> <o:SmartTagType namespaceuri="urn:schemas-microsoft-com:office:smarttags" name="PlaceType"/> <o:SmartTagType namespaceuri="urn:schemas-microsoft-com:office:smarttags" name="PlaceName"/> <o:SmartTagType namespaceuri="urn:schemas-microsoft-com:office:smarttags" name="address"/> <o:SmartTagType namespaceuri="urn:schemas-microsoft-com:office:smarttags" name="State"/> <o:SmartTagType namespaceuri="urn:schemas-microsoft-com:office:smarttags" name="City"/> <o:SmartTagType namespaceuri="urn:schemas-microsoft-com:office:smarttags" name="country-region"/> <o:SmartTagType namespaceuri="urn:schemas-microsoft-com:office:smarttags" name="place"/> <!--[if gte mso 9]><xml> <o:DocumentProperties> <o:Author>Jim Titus in 2009</o:Author> <o:LastAuthor>Jim Titus in 2009</o:LastAuthor> <o:Revision>3</o:Revision> <o:TotalTime>22</o:TotalTime> <o:Created>2009-04-17T11:21:00Z</o:Created> <o:LastSaved>2009-04-17T11:28:00Z</o:LastSaved> <o:Pages>1</o:Pages> <o:Words>6204</o:Words> <o:Characters>35366</o:Characters> <o:Company>EPA</o:Company> <o:Lines>294</o:Lines> <o:Paragraphs>82</o:Paragraphs> <o:CharactersWithSpaces>41488</o:CharactersWithSpaces> <o:Version>11.9999</o:Version> </o:DocumentProperties> </xml><![endif]--><!--[if gte mso 9]><xml> <w:WordDocument> <w:SpellingState>Clean</w:SpellingState> <w:GrammarState>Clean</w:GrammarState> <w:ValidateAgainstSchemas/> <w:SaveIfXMLInvalid>false</w:SaveIfXMLInvalid> <w:IgnoreMixedContent>false</w:IgnoreMixedContent> <w:AlwaysShowPlaceholderText>false</w:AlwaysShowPlaceholderText> <w:BrowserLevel>MicrosoftInternetExplorer4</w:BrowserLevel> </w:WordDocument> </xml><![endif]--><!--[if gte mso 9]><xml> <w:LatentStyles DefLockedState="false" LatentStyleCount="156"> </w:LatentStyles> </xml><![endif]--><!--[if !mso]><object classid="clsid:38481807-CA0E-42D2-BF39-B33AF135CC4D" id=ieooui></object> <style> st1\:*{behavior:url(#ieooui) } </style> <![endif]--> <style> <!-- /* Font Definitions */ @font-face {font-family:Wingdings; 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Titus and J. Wang entitled &quot;Maps of lands close to sea level along the middle Atlantic coast of the </a><st1:country-region w:st="on"><st1:place w:st="on"><span style='mso-bookmark:Top'>United States</span></st1:place></st1:country-region><span style='mso-bookmark:Top'>.&quot;</span></h1> <h2><span style='mso-bookmark:Top'>Metadata:</span></h2> <span style='mso-bookmark:Top'></span> <ul type=disc> <li class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l0 level1 lfo1;tab-stops:list .5in'><a href="#Identification_Information"><span class=SpellE>Identification_Information</span></a></li> <li class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l0 level1 lfo1;tab-stops:list .5in'><a href="#Data_Quality_Information"><span class=SpellE>Data_Quality_Information</span></a></li> <li class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l0 level1 lfo1;tab-stops:list .5in'><a href="#Spatial_Data_Organization_Information"><span class=SpellE>Spatial_Data_Organization_Information</span></a></li> <li class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l0 level1 lfo1;tab-stops:list .5in'><a href="#Spatial_Reference_Information"><span class=SpellE>Spatial_Reference_Information</span></a></li> <li class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l0 level1 lfo1;tab-stops:list .5in'><a href="#Entity_and_Attribute_Information"><span class=SpellE>Entity_and_Attribute_Information</span></a></li> <li class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l0 level1 lfo1;tab-stops:list .5in'><a href="#271383040"><span class=SpellE>Distribution_Information</span> </a></li> <li class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto; mso-list:l0 level1 lfo1;tab-stops:list .5in'><a href="#Metadata_Reference_Information"><span class=SpellE>Metadata_Reference_Information</span></a></li> </ul> <div class=MsoNormal align=center style='text-align:center'><a name="Identification_Information"> <hr size=2 width="100%" align=center> </a></div> <span style='font-size:12.0pt;font-family:"Times New Roman";mso-fareast-font-family: "Times New Roman";mso-ansi-language:EN-US;mso-fareast-language:EN-US; mso-bidi-language:AR-SA'><span style='mso-bookmark:Identification_Information'></span></span> <p class=MsoNormal><span class=SpellE><i>Identification_Information</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Citation:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Citation_Information</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Originator:</i> US Environmental Protection Agency</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Publication_Date</i></span><i>:</i> February 2008</p> <p class=MsoNormal style='margin-left:.5in'><i>Title:</i></p> <p class=MsoNormal style='margin-left:.5in'>District of Columbia Elevation Data underlying analysis by J.G. Titus and J. Wang entitled &quot;Maps of lands close to sea level along the middle Atlantic coast of the <st1:country-region w:st="on"><st1:place w:st="on">United States</st1:place></st1:country-region>.&quot;</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Geospatial_Data_Presentation_Form</i></span><i>:</i> raster digital data</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Other_Citation_Details</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'>Data underlying the analysis reported in J.G. Titus and J. Wang, 2008.</p> <p class=MsoNormal style='margin-left:.5in'><i><span lang=DE style='mso-ansi-language: DE'>Online_Linkage:</span></i><span lang=DE style='mso-ansi-language:DE'> <a href="http://maps.risingsea.net/data.html">http://maps.risingsea.net/data.html</a><o:p></o:p></span></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Larger_Work_Citation</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Citation_Information</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Originator:</i> US Environmental Protection Agency</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Publication_Date</i></span><i>:</i> February 2008</p> <p class=MsoNormal style='margin-left:.5in'><i>Title:</i></p> <p class=MsoNormal style='margin-left:.5in'>Maps of lands close to sea level along the middle Atlantic coast of the <st1:country-region w:st="on"><st1:place w:st="on">United States</st1:place></st1:country-region></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Other_Citation_Details</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'>Full Citation: Titus, J.G. and J. Wang, 2008: Maps of lands close to sea level along the middle Atlantic coast of the <st1:country-region w:st="on"><st1:place w:st="on">United States</st1:place></st1:country-region>: an elevation data set to use while waiting for LIDAR. In: Background Documents Supporting Climate Change Science Program Synthesis and Assessment Product 4.1: Coastal Elevations and Sensitivity to Sea Level Rise [J.G. Titus and E.M. Strange (<span class=GramE>eds</span>.)]. <span class=GramE>EPA430R07004, <st1:country-region w:st="on">U.S.</st1:country-region> Environmental <st1:place w:st="on"><st1:City w:st="on">Protection Agency</st1:City>, <st1:State w:st="on">Washington</st1:State></st1:place>, DC.</span></p> <p class=MsoNormal style='margin-left:.5in'><i>Description:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Abstract:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>The <st1:State w:st="on"><st1:place w:st="on">District of Columbia</st1:place></st1:State> Digital Elevation Model</pre><pre style='margin-left:.5in'>(Environmental Systems Research Institute [ESRI] Grid</pre><pre style='margin-left:.5in'><span class=GramE>format</span>) represents an elevation map of the District of</pre><pre style='margin-left:.5in'><st1:City w:st="on"><st1:place w:st="on">Columbia</st1:place></st1:City> coastal zone created for the purposes of analyzing</pre><pre style='margin-left:.5in'><span class=GramE>vulnerability</span> to rising sea level.</pre><pre style='margin-left:.5in'>The domain of the data includes <span class=GramE>all of the</span> District of</pre><pre style='margin-left:.5in'><st1:City w:st="on"><st1:place w:st="on">Columbia</st1:place></st1:City>, but the primary focus of the analytical approach and</pre><pre style='margin-left:.5in'><span class=GramE>quality</span> control has focused on land below the 10 foot</pre><pre style='margin-left:.5in'><span class=GramE>contour</span>. This data set has been derived from National</pre><pre style='margin-left:.5in'>Capital Planning Commission and <st1:State w:st="on"><st1:place w:st="on">District of Columbia</st1:place></st1:State></pre><pre style='margin-left:.5in'>Department of Public Works Ground Elevation Data. In</pre><pre style='margin-left:.5in'><span class=GramE>addition</span>, the analysis created a supplemental contour</pre><pre style='margin-left:.5in'><span class=GramE>representing</span> the elevation of spring high water</pre><pre style='margin-left:.5in'>(SHW), which is generally between 1.5 and 3 feet above</pre><pre style='margin-left:.5in'><span class=GramE>NGVD29 in the <st1:State w:st="on"><st1:place w:st="on">District of Columbia</st1:place></st1:State>.</span> We defined the horizontal</pre><pre style='margin-left:.5in'><span class=GramE>position</span> of that contour using polygon tidal wetlands</pre><pre style='margin-left:.5in'><span class=GramE>data</span> from the US Fish and Wildlife Service National</pre><pre style='margin-left:.5in'>Wetlands Inventory (NWI). We defined the vertical</pre><pre style='margin-left:.5in'><span class=GramE>position</span> of the supplemental contour by creating a</pre><pre style='margin-left:.5in'>&quot;<span class=GramE>tidal</span> elevation surface&quot; using the <st1:place w:st="on"><st1:PlaceName w:st="on">National</st1:PlaceName> <st1:PlaceType w:st="on">Ocean</st1:PlaceType></st1:place></pre><pre style='margin-left:.5in'>Service's (NOS) estimated tide ranges, the NOS</pre><pre style='margin-left:.5in'><span class=GramE>estimated</span> sea level trends, the NOS published benchmark</pre><pre style='margin-left:.5in'><span class=GramE>sheets</span> and the National Geodetic Survey North American</pre><pre style='margin-left:.5in'>Vertical Datum Conversion Utility (VERTCON) program to</pre><pre style='margin-left:.5in'><span class=GramE>convert</span> the Mean Tide Level (MTL) relative to NAVD88 to a</pre><pre style='margin-left:.5in'>NGVD29. All elevation information was converted to a</pre><pre style='margin-left:.5in'><span class=GramE>common</span> vertical reference (usually NGVD29) and the DEM</pre><pre style='margin-left:.5in'><span class=GramE>was</span> generated from that input data using <span class=SpellE>ESRI's</span></pre><pre style='margin-left:.5in'><span class=GramE>interpolation</span> algorithm TOPOGRID (within <span class=SpellE>ArcGIS</span></pre><pre style='margin-left:.5in'><span class=GramE>workstation</span> GRID extension). We converted the absolute</pre><pre style='margin-left:.5in'><span class=GramE>elevation</span> estimates (usually NGVD29) into elevations relative to </pre><pre style='margin-left:.5in'><span class=GramE>SHW using the &quot;tidal elevation surface&quot;.</span> For purposes of this </pre><pre style='margin-left:.5in'><span class=GramE>data</span> set, SHW is the upper boundary of tidal wetlands (including </pre><pre style='margin-left:.5in'><span class=GramE>vegetated</span> wetlands and intertidal beaches). Elevation is</pre><pre style='margin-left:.5in'><span class=GramE>expressed</span> in cm.</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>The zip file associated with this data set should</pre><pre style='margin-left:.5in'><span class=GramE>include</span>:</pre><pre style='margin-left:.5in'>1.<span style='mso-spacerun:yes'>   </span>README_DC_Elevation.doc, which provides a brief overview of the</pre><pre style='margin-left:.5in'><span class=GramE>relationship</span> between this dataset and related data</pre><pre style='margin-left:.5in'>2.<span style='mso-spacerun:yes'>   </span>InterpolationMethods_MEMO.doc</pre><pre style='margin-left:.5in'>3.<span style='mso-spacerun:yes'>   </span><span class=SpellE>MD_Data_Quality.jpg</span></pre><pre style='margin-left:.5in'>4.<span style='mso-spacerun:yes'>   </span>DEM_LidarComparisonTable.doc</pre><pre style='margin-left:.5in'>5.<span style='mso-spacerun:yes'>   </span>DEM_Comparison_with_DLG_11_quads.xls</pre><pre style='margin-left:.5in'>6.<span style='mso-spacerun:yes'>   </span>Institute_of_Geography_DLG.xls</pre><pre style='margin-left:.5in'>7.<span style='mso-spacerun:yes'>   </span>Titus_and_Wang_2008.pdf</pre><pre style='margin-left:.5in'>However, to speed download, (2) and (7) which are associated with all of the states may have been removed</pre><pre style='margin-left:.5in'><span class=GramE>and</span> included in a file called  <span class=SpellE>Common_supplemental_metadata.zip</span> </pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><i>Purpose:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>The District of Columbia Digital Elevation Model provides a</pre><pre style='margin-left:.5in'><span class=GramE>base</span> map layer for assessing the possible influences of</pre><pre style='margin-left:.5in'><span class=GramE>potential</span> sea level rise on coast regions. We recommend against </pre><pre style='margin-left:.5in'><span class=GramE>using</span> this data to create maps with scales greater than 1:100,000, </pre><pre style='margin-left:.5in'><span class=GramE>regardless</span> of the level of vertical precision portrayed.<span style='mso-spacerun:yes'>  </span>Moreover, </pre><pre style='margin-left:.5in'><span class=GramE>if</span> the purpose of using this data is to create graphical depictions </pre><pre style='margin-left:.5in'><span class=GramE>of</span> risk with contour intervals of 50-100 cm, we recommend a </pre><pre style='margin-left:.5in'><span class=GramE>considerably</span> smaller scale unless the audience is likely to understand </pre><pre style='margin-left:.5in'><span class=GramE>the</span> limitations of the data.</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><span class=SpellE><i>Supplemental_Information</i></span><i>:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original><span class=GramE>Elevations relative to year 2000.</span></pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><span class=SpellE><i>Time_Period_of_Content</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Time_Period_Information</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Single_Date</i></span><i>/Time:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Calendar_Date</i></span><i>:</i> 2000</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Currentness_Reference</i></span><i>:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original><span class=GramE>ground</span> condition</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><i>Status:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Progress:</i> Complete</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Maintenance_and_Update_Frequency</i></span><i>:</i> None planned</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Spatial_Domain</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Bounding_Coordinates</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>West_Bounding_Coordinate</i></span><i>:</i> -77.189819</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>East_Bounding_Coordinate</i></span><i>:</i> -76.845663</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>North_Bounding_Coordinate</i></span><i>:</i> 39.036284</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>South_Bounding_Coordinate</i></span><i>:</i> 38.718194</p> <p class=MsoNormal style='margin-left:.5in'><i>Keywords:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Theme:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Theme_Keyword_Thesaurus</i></span><i>:</i> General</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Theme_Keyword</i></span><i>:</i> <st1:place w:st="on"><st1:City w:st="on">Washington</st1:City> <st1:State w:st="on">District of Columbia</st1:State></st1:place> Elevation</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Theme_Keyword</i></span><i>:</i> DEM</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Theme_Keyword</i></span><i>:</i> Coastal Elevation</p> <p class=MsoNormal style='margin-left:.5in'><i>Place:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Place_Keyword</i></span><i>:</i> DC</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Access_Constraints</i></span><i>:</i> None</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Use_Constraints</i></span><i>:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>None</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><span class=SpellE><i>Point_of_Contact</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Information</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Person_Primary</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Person</i></span><i>:</i> James G. Titus</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Organization</i></span><i>:</i> <st1:country-region w:st="on"><st1:place w:st="on">U.S.</st1:place></st1:country-region> Environmental Protection Agency, Climate Change Division</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Position</i></span><i>:</i> Project Manager</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Address</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Address_Type</i></span><i>:</i> mailing address</p> <p class=MsoNormal style='margin-left:.5in'><i>Address:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original><span class=SpellE>Mailcode</span> 6207J</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><i>City:</i> <st1:State w:st="on"><st1:place w:st="on">Washington</st1:place></st1:State></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>State_or_Province</i></span><i>:</i> DC</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Postal_Code</i></span><i>:</i> 20460</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Voice_Telephone</i></span><i>:</i> 202-343-9307</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Facsimile_Telephone</i></span><i>:</i> 202-343-2338</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Electronic_Mail_Address</i></span><i>:</i> Titus.Jim@epamail.epa.gov</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Hours_of_Service</i></span><i>:</i> 9:00 - 6:00 Eastern</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Data_Set_Credit</i></span><i>:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original><span class=SpellE><span class=GramE>Jue</span></span><span class=GramE> Wang, GIS Practice, ICF Consulting, Inc.</span></pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><span class=SpellE><i>Native_Data_Set_Environment</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'>Microsoft Windows XP Version 5.1 (Build 2600) Service Pack 2; ESRI <span class=SpellE>ArcCatalog</span> 9.3.0.1770</p> <p class=MsoNormal><a href="#Top">Back to Top</a> <a name="Data_Quality_Information"></a></p> <div class=MsoNormal align=center style='text-align:center'><span style='mso-bookmark:Data_Quality_Information'> <hr size=2 width="100%" align=center> </span></div> <span style='font-size:12.0pt;font-family:"Times New Roman";mso-fareast-font-family: "Times New Roman";mso-ansi-language:EN-US;mso-fareast-language:EN-US; mso-bidi-language:AR-SA'><span style='mso-bookmark:Data_Quality_Information'></span></span> <p class=MsoNormal><span class=SpellE><i>Data_Quality_Information</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Attribute_Accuracy</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Attribute_Accuracy_Report</i></span><i>:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>The underlying data used in the creation of this layer may contain errors or omissions. </pre><pre style='margin-left:.5in'>The accuracy of this data set generally corresponds to the source data used in the </pre><pre style='margin-left:.5in'><span class=GramE>layer</span> development. See &quot;<span class=SpellE>DC_Data_Quality.jpg</span>&quot; <span class=GramE>for<span style='mso-spacerun:yes'>  </span>an</span> index of the source data used </pre><pre style='margin-left:.5in'>(<span class=GramE>that</span> accompanied this data set in the zip file.)</pre><pre style='margin-left:.5in'>See the sections on Positional Accuracy for more detailed information.</pre><pre style='margin-left:.5in'>Additional consideration: The vertical values and their associated positions were </pre><pre style='margin-left:.5in'><span class=GramE>generated</span> using the interpolation function &quot;TOPOGRID&quot; within the ESRI GRID module. </pre><pre style='margin-left:.5in'>TOPOGRID uses input elevation data such as contours and elevation point data along </pre><pre style='margin-left:.5in'><span class=GramE>with</span> supplemental information such as stream networks, lakes (of known elevation), and </pre><pre style='margin-left:.5in'><span class=GramE>bounding</span> areas to generate a <span class=SpellE>hydrologically</span>-correct DEM. Each state DEM was </pre><pre style='margin-left:.5in'><span class=GramE>generated</span> using TOPOGRID but the specific parameters were unique to the data sets </pre><pre style='margin-left:.5in'><span class=GramE>available</span> and issues related to each state.</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>There are known issues relating to the interpolation algorithm TOPOGRID.</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'><span class=GramE>TOPOGRID Plateau Problem.</span> The TOPOGRID function generates disproportionately </pre><pre style='margin-left:.5in'><span class=GramE>large</span> areas with the same value of the input contour lines, e.g., if we have 5 and 10 foot </pre><pre style='margin-left:.5in'><span class=GramE>contour</span> lines, there would be substantially more areas with values between 4 to 6 and </pre><pre style='margin-left:.5in'><span class=GramE>9 to 11, than 6 to 9 feet.</span> At the upper tips of narrow valleys, the cell values tend to be </pre><pre style='margin-left:.5in'><span class=GramE>the</span> same as the bounding contours so the valleys become plateaus. The TOPOGRID </pre><pre style='margin-left:.5in'><span class=GramE>function</span> within the ESRI GRID module tends to calculate a trend from neighboring </pre><pre style='margin-left:.5in'><span class=GramE>contour</span> lines. As a result, TOPOGRID frequently creates areas of erroneous depressions </pre><pre style='margin-left:.5in'><span class=GramE>on</span> the plains adjacent to steep slopes, often substantially below the contours between </pre><pre style='margin-left:.5in'><span class=GramE>which</span> those depressions lay. It also creates plateaus along contours, which can be </pre><pre style='margin-left:.5in'><span class=GramE>problematic</span> because they overstate the amount of land barely above the wetlands </pre><pre style='margin-left:.5in'><span class=GramE>and</span> right at the first contour, while understating the amount of land halfway between </pre><pre style='margin-left:.5in'><span class=GramE>the</span> wetlands and the first contour. To address these problems, we processed the </pre><pre style='margin-left:.5in'><span class=GramE>areas</span> above and below the first contour separately. However, this caused another </pre><pre style='margin-left:.5in'><span class=GramE>problem</span>. In narrow valleys in the area below the first contour, the output DEM values </pre><pre style='margin-left:.5in'><span class=GramE>were</span> similar or identical to those of the bounding contour lines due to the lack of </pre><pre style='margin-left:.5in'><span class=GramE>elevation</span> information that TOPOGRID needs to calculate trend. The most problematic </pre><pre style='margin-left:.5in'><span class=GramE>regions</span> occurred where there was a stream valley below the first contour (e.g. between </pre><pre style='margin-left:.5in'><span class=GramE>two</span> parallel 5 foot contours), neither open water nor tidal wetlands along most of the </pre><pre style='margin-left:.5in'><span class=GramE>length</span> of the valley, but open water or tidal wetlands at one end of the valley (e.g. a </pre><pre style='margin-left:.5in'><span class=GramE>typical</span> non-tidal stream flowing into tidal waters). In some cases, the trend from the </pre><pre style='margin-left:.5in'><span class=GramE>wetlands</span> or open water at the mouth toward the bounding first contour would provide </pre><pre style='margin-left:.5in'><span class=GramE>values</span> even higher than that first contour farther up the valley. And in general, </pre><pre style='margin-left:.5in'>TOPOGRID would be more likely to assume a flat area between the contours, </pre><pre style='margin-left:.5in'><span class=GramE>than</span> to characterize it as a valley.</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>We did not use stream data in constructing the DEM for the <st1:State w:st="on"><st1:place w:st="on">District of Columbia</st1:place></st1:State>. (See comparable </pre><pre style='margin-left:.5in'><span class=SpellE><span class=GramE>DEMs</span></span><span class=GramE> for <st1:State w:st="on">Delaware</st1:State>, <st1:State w:st="on">Maryland</st1:State>, <st1:State w:st="on">New York</st1:State> and <st1:State w:st="on"><st1:place w:st="on">North Carolina</st1:place></st1:State>, where stream data was available.).</span></pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'><span class=GramE>Evaluation of other interpolation methods.</span> </pre><pre style='margin-left:.5in'>Several interpolation methods were evaluated before the TOPOGRID function was </pre><pre style='margin-left:.5in'><span class=GramE>selected</span>. Specifically, <span class=SpellE>Spline</span>, Inverse Distance Weighting (IDW), and Triangulated </pre><pre style='margin-left:.5in'>Irregular Network (TIN) methods were evaluated and compared to the TOPOGRID </pre><pre style='margin-left:.5in'><span class=GramE>function</span>. Statistics and graphical examples of cross sections specific to each </pre><pre style='margin-left:.5in'><span class=GramE>interpolation</span> method are presented in the accompanying </pre><pre style='margin-left:.5in'>&quot;InterpolationMethods_MEMO.doc&quot; memo included in the zip file associated with </pre><pre style='margin-left:.5in'><span class=GramE>this</span> data set.</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><span class=SpellE><i>Attribute_Accuracy</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Quantitative_Attribute_Accuracy_Assessment</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Attribute_Accuracy_Explanation</i></span><i>:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>Vertical values were rounded to nearest whole cm. See</pre><pre style='margin-left:.5in'><span class=GramE>the</span> sections on Positional Accuracy (Horizontal and</pre><pre style='margin-left:.5in'><span class=GramE>Vertical).</span></pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><span class=SpellE><i>Logical_Consistency_Report</i></span><i>:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>Refer to the Titus and Wang 2008 technical report that documents this study for information on the publication date for data and procedures used in the development of this layer.</pre><pre style='margin-left:.5in'>See the sections on Positional Accuracy (Horizontal and Vertical) for additional information.</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>Note that the discussions presented in the accuracy</pre><pre style='margin-left:.5in'><span class=GramE>reports</span> refer to contour intervals in multiple units</pre><pre style='margin-left:.5in'>(<span class=GramE>meters</span> and feet). This was done purposefully to</pre><pre style='margin-left:.5in'><span class=GramE>reflect</span> the actual contour intervals used by USGS over</pre><pre style='margin-left:.5in'><span class=GramE>the</span> years and which vary on a quadrangle by quadrangle</pre><pre style='margin-left:.5in'><span class=GramE>basis</span>.</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><span class=SpellE><i>Completeness_Report</i></span><i>:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>This elevation data set generally corresponds to that of the</pre><pre style='margin-left:.5in'><span class=GramE>source</span> data used in the layer development. See the</pre><pre style='margin-left:.5in'><span class=GramE>sections</span> on Positional Accuracy (Horizontal and</pre><pre style='margin-left:.5in'><span class=GramE>Vertical) for additional information.</span></pre><pre style='margin-left:.5in'>The vertical values and their associated positions were</pre><pre style='margin-left:.5in'><span class=GramE>generated</span> using the interpolation function &quot;TOPOGRID&quot;</pre><pre style='margin-left:.5in'><span class=GramE>within</span> the ESRI GRID module. TOPOGRID uses input</pre><pre style='margin-left:.5in'><span class=GramE>elevation</span> data such as contours and elevation point</pre><pre style='margin-left:.5in'><span class=GramE>data</span> along with supplemental information such as stream</pre><pre style='margin-left:.5in'><span class=GramE>networks</span>, lakes (of known elevation), and bounding</pre><pre style='margin-left:.5in'><span class=GramE>areas</span> to generate a <span class=SpellE>hydrologically</span> correct DEM. Each</pre><pre style='margin-left:.5in'><span class=GramE>state</span> DEM was generated using TOPOGRID but the specific</pre><pre style='margin-left:.5in'><span class=GramE>parameters</span> were unique to the data sets available and</pre><pre style='margin-left:.5in'><span class=GramE>issues</span> related to each state. The specifics to each</pre><pre style='margin-left:.5in'><span class=GramE>state</span> DEM are described under positional accuracy</pre><pre style='margin-left:.5in'><span class=GramE>section</span> of the metadata and in process steps.</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>There are known issues relating to the interpolation</pre><pre style='margin-left:.5in'><span class=GramE>algorithm</span> TOPOGRID.</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'><span class=GramE>TOPOGRID Plateau Problem.</span><span style='mso-spacerun:yes'>  </span>The TOPOGRID function</pre><pre style='margin-left:.5in'><span class=GramE>generates</span> disproportionately large areas with the same</pre><pre style='margin-left:.5in'><span class=GramE>value</span> of the input contour lines, e.g., if we have 5</pre><pre style='margin-left:.5in'><span class=GramE>and</span> 10 foot contour lines, there would be substantially</pre><pre style='margin-left:.5in'><span class=GramE>more</span> areas with values between 4 to 6 and 9 to 11, than</pre><pre style='margin-left:.5in'><span class=GramE>6 to 9 feet.</span> At the upper tips of narrow valleys, the</pre><pre style='margin-left:.5in'><span class=GramE>cell</span> values tend to be the same as the bounding</pre><pre style='margin-left:.5in'><span class=GramE>contours</span> so the valleys become plateaus.</pre><pre style='margin-left:.5in'>The TOPOGRID function within the ESRI GRID module tends</pre><pre style='margin-left:.5in'><span class=GramE>to</span> calculate a trend from neighboring contour lines.</pre><pre style='margin-left:.5in'>As a result, TOPOGRID frequently <span class=GramE>creates<span style='mso-spacerun:yes'>  </span>areas</span> of</pre><pre style='margin-left:.5in'><span class=GramE>erroneous</span> depressions on the plains adjacent to steep</pre><pre style='margin-left:.5in'><span class=GramE>slopes</span>, often substantially below the contours between</pre><pre style='margin-left:.5in'><span class=GramE>which</span> those depressions lie. It also creates plateaus</pre><pre style='margin-left:.5in'><span class=GramE>along</span> contours, which can be problematic because they</pre><pre style='margin-left:.5in'><span class=GramE>overstate</span> the amount of land barely above the wetlands</pre><pre style='margin-left:.5in'><span class=GramE>and</span> right at the first contour, while understating the</pre><pre style='margin-left:.5in'><span class=GramE>amount</span> of land halfway between the wetlands and the</pre><pre style='margin-left:.5in'><span class=GramE>first</span> contour. To address these problems, we processed</pre><pre style='margin-left:.5in'><span class=GramE>the</span> areas above and below the first contour separately.</pre><pre style='margin-left:.5in'>However, this caused another problem. In narrow valleys</pre><pre style='margin-left:.5in'><span class=GramE>in</span> the area below the first contour, the output DEM</pre><pre style='margin-left:.5in'><span class=GramE>values</span> were similar or identical to those of the</pre><pre style='margin-left:.5in'><span class=GramE>bounding</span> contour lines due to the lack of elevation</pre><pre style='margin-left:.5in'><span class=GramE>information</span> that TOPOGRID needs to calculate trend. The</pre><pre style='margin-left:.5in'><span class=GramE>most</span> problematic regions occurred where there was a</pre><pre style='margin-left:.5in'><span class=GramE>stream</span> valley below the first contour (e.g. between two</pre><pre style='margin-left:.5in'><span class=GramE>parallel</span> 5 foot contours), no open water or tidal</pre><pre style='margin-left:.5in'><span class=GramE>wetlands</span> along most of the length of the valley, but</pre><pre style='margin-left:.5in'><span class=GramE>open</span> water or tidal wetlands at one end of the valley</pre><pre style='margin-left:.5in'>(<span class=GramE>e.g</span>. a typical nontidal stream flowing into tidal</pre><pre style='margin-left:.5in'><span class=GramE>waters</span>). In some cases, the trend from the wetlands or</pre><pre style='margin-left:.5in'><span class=GramE>open</span> water at the mouth toward the bounding first</pre><pre style='margin-left:.5in'><span class=GramE>contour</span>, would provide values even higher than that</pre><pre style='margin-left:.5in'><span class=GramE>first</span> contour farther up the valley. And in general,</pre><pre style='margin-left:.5in'>TOPOGRID would be more likely to assume a flat area</pre><pre style='margin-left:.5in'><span class=GramE>between</span> the contours, than to characterize it as a</pre><pre style='margin-left:.5in'><span class=GramE>valley</span>.</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>Omissions: Neither stream networks nor lake features</pre><pre style='margin-left:.5in'><span class=GramE>were</span> used as inputs into the TOPOGRID function in</pre><pre style='margin-left:.5in'><span class=GramE>creation</span> of this data set. The absence of a hydrologic</pre><pre style='margin-left:.5in'><span class=GramE>network</span> explains a significant proportion of the greatest</pre><pre style='margin-left:.5in'><span class=GramE>errors</span> in the vicinity of non-tidal streams at elevations</pre><pre style='margin-left:.5in'><span class=GramE>below</span> the first contour. TOPOGRID infers stream valleys</pre><pre style='margin-left:.5in'><span class=GramE>above</span> the first contour by the pattern of a valley without</pre><pre style='margin-left:.5in'><span class=GramE>the</span> stream data. The decision to split the data into land</pre><pre style='margin-left:.5in'><span class=GramE>below</span> and above the first contour (discussed in process</pre><pre style='margin-left:.5in'><span class=GramE>step</span> #4 &quot;Interpolation of Digital Elevation Model &quot;) had</pre><pre style='margin-left:.5in'><span class=GramE>the</span> effect of increasing the potential errors resulting from </pre><pre style='margin-left:.5in'><span class=GramE>the</span> absence of stream data. However, the magnitude of</pre><pre style='margin-left:.5in'><span class=GramE>any</span> errors induced by this problem was limited by the</pre><pre style='margin-left:.5in'>&quot;<span class=GramE>first</span> contour truncating&quot; (also discussed in process step </pre><pre style='margin-left:.5in'><span class=GramE>#4).</span> The net effect was to put back some of the plateaus </pre><pre style='margin-left:.5in'><span class=GramE>eliminated</span> by dividing the data, but not all of those plateaus. </pre><pre style='margin-left:.5in'>Moreover, errors introduced by the omission of non-tidal streams were </pre><pre style='margin-left:.5in'><span class=GramE>absent</span> in areas where tidal streams or tidal wetlands were present, which served the same function.</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>Other Issues: In addition to excluding streams, the</pre><pre style='margin-left:.5in'><span class=GramE>decision</span> to process 3 elevation areas separately within</pre><pre style='margin-left:.5in'>TOPOGRID (as described in the process step #4 -</pre><pre style='margin-left:.5in'>&quot;Interpolation of Digital Elevation Model&quot;) and then</pre><pre style='margin-left:.5in'><span class=GramE>combine</span> them into a single DEM removes the algorithm</pre><pre style='margin-left:.5in'><span class=GramE>from</span> its theoretical underpinning, because it separates</pre><pre style='margin-left:.5in'><span class=GramE>each</span> elevation zone from the context of the overall</pre><pre style='margin-left:.5in'><span class=GramE>environment</span> that TOPOGRID uses to generate a</pre><pre style='margin-left:.5in'><span class=SpellE><span class=GramE>hydrologically</span></span><span class=GramE>-correct</span> DEM. Because the objective of</pre><pre style='margin-left:.5in'><span class=GramE>this</span> DEM is to estimate elevations of lands close to</pre><pre style='margin-left:.5in'><span class=GramE>sea</span> level, rather than characterize drainage correctly,</pre><pre style='margin-left:.5in'><span class=GramE>the</span> ad hoc response to the TOPOGRID plateau problem is</pre><pre style='margin-left:.5in'><span class=GramE>not</span> as unreasonable as would have been the case were</pre><pre style='margin-left:.5in'><span class=GramE>this</span> data to be used for analyzing hydrology.</pre><pre style='margin-left:.5in'>Nevertheless, the inclusion of an accurate stream</pre><pre style='margin-left:.5in'><span class=GramE>network</span>, modification of the tolerance values and other</pre><pre style='margin-left:.5in'><span class=GramE>parameters</span> within TOPOGRID, and inclusion of additional</pre><pre style='margin-left:.5in'><span class=GramE>vertical</span> data in areas of known errors (determined</pre><pre style='margin-left:.5in'><span class=GramE>through</span> the use of diagnostic outputs within the</pre><pre style='margin-left:.5in'>TOPOGRID function), probably could have substantially</pre><pre style='margin-left:.5in'><span class=GramE>diminished</span> the plateau problem in the vicinity of the</pre><pre style='margin-left:.5in'><span class=GramE>first</span> topographic contour. Because the plateau problem</pre><pre style='margin-left:.5in'><span class=GramE>around</span> the edge of tidal wetlands was often caused</pre><pre style='margin-left:.5in'><span class=GramE>largely</span> by the relative complexity of the wetland</pre><pre style='margin-left:.5in'><span class=GramE>supplemental</span> contour compared with other contours, and</pre><pre style='margin-left:.5in'><span class=GramE>because</span> the tidal wetlands and open water data which we</pre><pre style='margin-left:.5in'><span class=GramE>used</span> in effect provide the stream data, the case for</pre><pre style='margin-left:.5in'><span class=GramE>dividing</span> the data as we did is probably greater along</pre><pre style='margin-left:.5in'><span class=GramE>the</span> wetland boundary than along the first contour.</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>Also see the sections on Positional Accuracy</pre><pre style='margin-left:.5in'><span class=GramE>(Horizontal and Vertical) and process steps.</span></pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><span class=SpellE><i>Positional_Accuracy</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Horizontal_Positional_Accuracy</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Quantitative_Horizontal_Positional_Accuracy_Assessment</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Horizontal_Positional_Accuracy_Value</i></span><i>:</i> 40-42.5 meters</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Positional_Accuracy</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Horizontal_Positional_Accuracy</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Quantitative_Horizontal_Positional_Accuracy_Assessment</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Horizontal_Positional_Accuracy_Value</i></span><i>:</i> 40-42.5 meters</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Positional_Accuracy</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Horizontal_Positional_Accuracy</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Horizontal_Positional_Accuracy_Report</i></span><i>:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>The source data generally were 1:1000 <span class=GramE>scale</span>. Therefore</pre><pre style='margin-left:.5in'><span class=GramE>our</span> use of 30 meter cells deteriorated the horizontal</pre><pre style='margin-left:.5in'><span class=GramE>accuracy</span>.<span style='mso-spacerun:yes'>  </span>Assuming that 90% of well defined points are</pre><pre style='margin-left:.5in'><span class=GramE>within</span> 30 meters of the indicated location would imply</pre><pre style='margin-left:.5in'><span class=GramE>a</span> scale of 1:60,000 under National Map Accuracy</pre><pre style='margin-left:.5in'><span class=GramE>Standards.</span> (That assumption may be conservative because</pre><pre style='margin-left:.5in'>100% of the points in a 30 meter cell are less than</pre><pre style='margin-left:.5in'><span class=GramE>21.2 meters of the center of the cell.</span><span style='mso-spacerun:yes'>  </span>If the input</pre><pre style='margin-left:.5in'><span class=GramE>map</span> has 1:24,000 scale (well defined points within 12.2</pre><pre style='margin-left:.5in'><span class=GramE>meters</span>)<span style='mso-spacerun:yes'>  </span>and errors are random, then more than 90% of</pre><pre style='margin-left:.5in'><span class=GramE>the</span> points will be within 24.5 meters of the indicated</pre><pre style='margin-left:.5in'><span class=GramE>location</span>, which would imply a scale of 1:50,000.)</pre><pre style='margin-left:.5in'>However, our interpolation program may further</pre><pre style='margin-left:.5in'><span class=GramE>deteriorate</span> the horizontal accuracy.<span style='mso-spacerun:yes'>  </span>Under some </pre><pre style='margin-left:.5in'><span class=GramE>circumstances</span>, the horizontal error appears to be </pre><pre style='margin-left:.5in'><span class=GramE>as</span> great as the width of a cell.<span style='mso-spacerun:yes'>  </span>Given that the </pre><pre style='margin-left:.5in'><span class=GramE>diagonal</span> in this case would be 42.4 m, if errors </pre><pre style='margin-left:.5in'><span class=GramE>are</span> random, then the scale might be as poor </pre><pre style='margin-left:.5in'><span class=GramE>as</span> 1:86,000 in areas where those 1-cell errors </pre><pre style='margin-left:.5in'><span class=GramE>are</span> common .</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>Neither stream networks nor lake features were used as</pre><pre style='margin-left:.5in'><span class=GramE>inputs</span> into the TOPOGRID function in creation of this</pre><pre style='margin-left:.5in'><span class=GramE>data</span> set for reasons discussed in the completeness</pre><pre style='margin-left:.5in'><span class=GramE>report</span>. The addition of a hydrologic network would</pre><pre style='margin-left:.5in'><span class=GramE>increase</span> the accuracy of the resulting DEM.</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><span class=SpellE><i>Quantitative_Horizontal_Positional_Accuracy_Assessment</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Horizontal_Positional_Accuracy_Value</i></span><i>:</i> 40-42.5 meters</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Horizontal_Positional_Accuracy_Explanation</i></span><i>:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>In the event the horizontal error is as great as the width of a cell, the diagonal would be 42.4 m.</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><span class=SpellE><i>Vertical_Positional_Accuracy</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Vertical_Positional_Accuracy_Report</i></span><i>:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>The vertical accuracy of this data set generally </pre><pre style='margin-left:.5in'><span class=GramE>corresponds</span> to that of the source data (described </pre><pre style='margin-left:.5in'><span class=GramE>below</span>) used in the layer development, plus errors </pre><pre style='margin-left:.5in'><span class=GramE>induced</span> through the various processing steps. </pre><pre style='margin-left:.5in'>The most important processing errors</pre><pre style='margin-left:.5in'><span class=GramE>probably</span> concern the procedures used to interpolate</pre><pre style='margin-left:.5in'><span class=GramE>between</span> contours, which do not necessarily correspond</pre><pre style='margin-left:.5in'><span class=GramE>to</span> the actual geometry of the land surfaces. Therefore,</pre><pre style='margin-left:.5in'><span class=GramE>points</span> that are near a contour have greater accuracy</pre><pre style='margin-left:.5in'><span class=GramE>than</span> points that are farther away from a contour.</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>In order to assess the vertical accuracy <span class=GramE>of<span style='mso-spacerun:yes'>  </span><span class=SpellE>DEMs</span></span> </pre><pre style='margin-left:.5in'><span class=GramE>generated</span> by ICF Consulting, Russ Jones of </pre><pre style='margin-left:.5in'>Stratus Consulting Inc. compared <span class=SpellE>DEMs</span> with </pre><pre style='margin-left:.5in'>LIDAR data in two areas: 1) an area south of </pre><pre style='margin-left:.5in'>Rock Hall along the eastern <st1:place w:st="on"><st1:PlaceType w:st="on">shore</st1:PlaceType> of <st1:PlaceName w:st="on">Maryland</st1:PlaceName></st1:place>, </pre><pre style='margin-left:.5in'><span class=GramE>and</span> 2) portions of <st1:State w:st="on"><st1:place w:st="on">North Carolina</st1:place></st1:State>. Table 1 within </pre><pre style='margin-left:.5in'>DEM_LidarComparisonTable.doc summarizes the </pre><pre style='margin-left:.5in'><span class=GramE>comparison</span>. The analysis suggests a Root Mean</pre><pre style='margin-left:.5in'>Square (RMS) discrepancy between LIDAR and this DEM</pre><pre style='margin-left:.5in'><span class=GramE>approximately</span> one-half of the input contour interval in cases</pre><pre style='margin-left:.5in'><span class=GramE>where</span> the contour interval was 1 meter, 5 feet, or 2</pre><pre style='margin-left:.5in'><span class=GramE>meters</span>. In areas where the USGS contour interval was 20</pre><pre style='margin-left:.5in'><span class=GramE>feet</span> and we used MD DNR data for supplemental contours,</pre><pre style='margin-left:.5in'><span class=GramE>the</span> mean discrepancy (LIDAR-DEM) was -2.4 feet with a</pre><pre style='margin-left:.5in'>RMS discrepancy of 6 feet for DEM observations less</pre><pre style='margin-left:.5in'><span class=GramE>than</span> 10 feet. The error was much less (mean -1.1 feet,</pre><pre style='margin-left:.5in'>RMS 3.9 feet) for DEM values between 10 and 20 feet</pre><pre style='margin-left:.5in'>NGVD29. Most of the errors appear to be centered in</pre><pre style='margin-left:.5in'><st1:place w:st="on"><st1:PlaceName w:st="on">Caroline</st1:PlaceName> <st1:PlaceName w:st="on">County</st1:PlaceName></st1:place>, where the Maryland DNR data</pre><pre style='margin-left:.5in'><span class=GramE>incorrectly</span> showed a large area below 5 feet NGVD29.</pre><pre style='margin-left:.5in'>If the LIDAR comparison is applicable to the District of </pre><pre style='margin-left:.5in'><st1:City w:st="on"><st1:place w:st="on">Columbia</st1:place></st1:City>, one would expect an RMS error of approximately</pre><pre style='margin-left:.5in'>50 cm (i.e. similar to the areas in the <st1:place w:st="on">Eastern Shore</st1:place></pre><pre style='margin-left:.5in'><span class=GramE>of</span> <st1:State w:st="on"><st1:place w:st="on">Maryland</st1:place></st1:State> where the DEM also relied on input <span class=SpellE>DLG's</span></pre><pre style='margin-left:.5in'><span class=GramE>with</span> a one-meter contour interval).</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>Jones also provided histograms showing the</pre><pre style='margin-left:.5in'><span class=GramE>relationship</span> between input contour intervals and the</pre><pre style='margin-left:.5in'>DEM values, for 11 USGS 7.5' topographical quadrangles</pre><pre style='margin-left:.5in'><span class=GramE>in</span> the study area from <st1:State w:st="on">New York</st1:State> to <st1:State w:st="on"><st1:place w:st="on">North Carolina</st1:place></st1:State>, none</pre><pre style='margin-left:.5in'><span class=GramE>of</span> which were in the <st1:State w:st="on"><st1:place w:st="on">District of Columbia</st1:place></st1:State>.<span style='mso-spacerun:yes'>   </span>The</pre><pre style='margin-left:.5in'><span class=GramE>technical</span> paper by Titus and Wang (2008, listed in the</pre><pre style='margin-left:.5in'><span class=GramE>citation</span> section above) analyzes the results of that</pre><pre style='margin-left:.5in'><span class=GramE>comparison</span>. Note that this comparison was conducted </pre><pre style='margin-left:.5in'><span class=GramE>on</span> the initial DEM generated with TOPOGRID. As a </pre><pre style='margin-left:.5in'><span class=GramE>result</span> of this analysis, the minimum and maximum </pre><pre style='margin-left:.5in'><span class=GramE>elevation</span> limits were constrained to ensure that the </pre><pre style='margin-left:.5in'><span class=GramE>resulting</span> elevations were in accordance with the </pre><pre style='margin-left:.5in'><span class=GramE>input</span> data. (See &quot;First-contour truncating&quot; in the </pre><pre style='margin-left:.5in'><span class=GramE>process</span> step on interpolation of Digital Elevation Model).</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>Two quads in <span class=SpellE>Maryland.were</span> particularly problematic:</pre><pre style='margin-left:.5in'><span class=SpellE><span class=GramE>Broomes</span></span><span class=GramE> and <st1:place w:st="on">South River</st1:place>.</span><span style='mso-spacerun:yes'>  </span>For <st1:place w:st="on">South River</st1:place>, the DEM </pre><pre style='margin-left:.5in'><span class=GramE>underestimates</span> the amount of land below 5 ft by 50%.</pre><pre style='margin-left:.5in'>However, it is within 5% and 1% for the areas between 5-</pre><pre style='margin-left:.5in'><span class=GramE>10 and 10-15 ft, respectively.</span><span style='mso-spacerun:yes'>  </span>This error appears to</pre><pre style='margin-left:.5in'><span class=GramE>have</span> resulted because the land is sufficiently steep</pre><pre style='margin-left:.5in'><span class=GramE>that</span> particular cells will have more than one contour</pre><pre style='margin-left:.5in'><span class=GramE>crossing</span> them.<span style='mso-spacerun:yes'>  </span>The DEM assigns an average elevation to</pre><pre style='margin-left:.5in'><span class=GramE>the</span> cell.<span style='mso-spacerun:yes'>  </span>Assuming that the contours cross the centers</pre><pre style='margin-left:.5in'><span class=GramE>of</span> cells randomly, one would normally expect that the</pre><pre style='margin-left:.5in'><span class=GramE>amount</span> of higher and lower ground being &quot;averaged in&quot;</pre><pre style='margin-left:.5in'><span class=GramE>would</span> approximately offset each other, so that the DEM</pre><pre style='margin-left:.5in'><span class=GramE>should</span> find the same amount of land within a given</pre><pre style='margin-left:.5in'><span class=GramE>elevation</span> range as the input <span class=SpellE>DLG's</span>.<span style='mso-spacerun:yes'>  </span>Indeed, this</pre><pre style='margin-left:.5in'><span class=GramE>appears</span> to be the case for land at 10-15 ft.<span style='mso-spacerun:yes'>  </span>For land</pre><pre style='margin-left:.5in'><span class=GramE>below</span> 5 ft, however, there is higher ground but no lower</pre><pre style='margin-left:.5in'><span class=GramE>ground</span> to be &quot;averaged in.&quot;<span style='mso-spacerun:yes'>  </span>Therefore, an upward bias</pre><pre style='margin-left:.5in'><span class=GramE>is</span> created for the lowest areas.<span style='mso-spacerun:yes'>  </span>Such an upward bias</pre><pre style='margin-left:.5in'><span class=GramE>in</span> the lowest contour range could have been avoided</pre><pre style='margin-left:.5in'><span class=GramE>with</span> an algorithm that calculated elevations for points</pre><pre style='margin-left:.5in'><span class=GramE>rather</span> than cells or using a much smaller cell size.</pre><pre style='margin-left:.5in'>Doing so, however, would have increased the costs of</pre><pre style='margin-left:.5in'><span class=GramE>this</span> study several fold. The net impact was that the</pre><pre style='margin-left:.5in'>DEM, in effect, estimated the 5-ft contour to be</pre><pre style='margin-left:.5in'><span class=GramE>approximately</span> 7.3 ft above the vertical datum for South</pre><pre style='margin-left:.5in'><span class=GramE>River.</span><span style='mso-spacerun:yes'>  </span>The <span class=SpellE>Broomes</span> quad had a similar upward bias,</pre><pre style='margin-left:.5in'><span class=GramE>effectively</span> treating the 5-ft contour as a 5.8-ft</pre><pre style='margin-left:.5in'><span class=GramE>contour</span>.<span style='mso-spacerun:yes'>  </span>The experience with those two quads in</pre><pre style='margin-left:.5in'><st1:State w:st="on"><st1:place w:st="on">Maryland</st1:place></st1:State> should serve as a caution that in the </pre><pre style='margin-left:.5in'><st1:State w:st="on"><st1:place w:st="on">District of Columbia</st1:place></st1:State>, our results may be less accurate </pre><pre style='margin-left:.5in'><span class=GramE>in</span> areas with slopes steep enough to have two contours </pre><pre style='margin-left:.5in'><span class=GramE>within</span> 30 meters (e.g. slopes greater than 6% with </pre><pre style='margin-left:.5in'>5-ft contours, or 12% with 10ft contours), especially </pre><pre style='margin-left:.5in'><span class=GramE>in</span> the area above the lowest contour. However, </pre><pre style='margin-left:.5in'><span class=GramE>the</span> availability of a one-meter contour interval </pre><pre style='margin-left:.5in'><span class=GramE>substantially</span> mitigates this concern.</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>The results of the &quot;11 quadrangle&quot; analysis are shown in <span class=GramE>DEM_Comparison_with_DLG_11_quads.xls.,</span> </pre><pre style='margin-left:.5in'><span class=GramE>which</span> is included in the zip file distributed with this dataset.</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><span class=SpellE><i>Quantitative_Vertical_Positional_Accuracy_Assessment</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Vertical_Positional_Accuracy_Explanation</i></span><i>:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>See vertical accuracy report.</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><i>Lineage:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Source_Information</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Source_Citation</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Citation_Information</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Originator:</i> National Capital Planning Commission and District of Columbia Department of Public Works</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Publication_Date</i></span><i>:</i> 2001</p> <p class=MsoNormal style='margin-left:.5in'><i>Title:</i></p> <p class=MsoNormal style='margin-left:.5in'>Rooftop Elevation and Ground Elevation</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Source_Scale_Denominator</i></span><i>:</i> 1,000</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Type_of_Source_Media</i></span><i>:</i> Digital data</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Source_Time_Period_of_Content</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Source_Currentness_Reference</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'>2001</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Source_Contribution</i></span><i>:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>Elevation contours. Source contours are 1 meter interval.</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><span class=SpellE><i>Source_Information</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Source_Citation</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Citation_Information</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Originator:</i> National Oceanic Service</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Publication_Date</i></span><i>:</i> Unknown</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Publication_Time</i></span><i>:</i> Unknown</p> <p class=MsoNormal style='margin-left:.5in'><i>Title:</i></p> <p class=MsoNormal style='margin-left:.5in'>NOS Tide Observation Data</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Other_Citation_Details</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'>Accessed December 2005</p> <p class=MsoNormal style='margin-left:.5in'><i><span lang=DE style='mso-ansi-language: DE'>Online_Linkage:</span></i><span lang=DE style='mso-ansi-language:DE'> </span><a href="%3chttp://co-ops.nos.noaa.gov/bench.html%3e" target=viewer><span lang=DE style='mso-ansi-language:DE'>&lt;http://co-ops.nos.noaa.gov/bench.html&gt;</span></a><span style='mso-ansi-language:DE'> <span lang=DE><o:p></o:p></span></span></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Source_Scale_Denominator</i></span><i>:</i> 24000</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Type_of_Source_Media</i></span><i>:</i> online</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Source_Time_Period_of_Content</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Time_Period_Information</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Range_of_Dates</i></span><i>/Times:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Beginning_Date</i></span><i>:</i> 1960</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Ending_Date</i></span><i>:</i> 2000</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Source_Currentness_Reference</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'>Relative to 1960-1978 Tidal <span class=GramE>Epoch</span></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Source_Contribution</i></span><i>:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>Spatial coordinates and elevations of MTL relative to</pre><pre style='margin-left:.5in'><span class=GramE>mean</span> lower low water (MLLW), the elevation of MLLW</pre><pre style='margin-left:.5in'><span class=GramE>relative</span> to several benchmarks nearby, and the</pre><pre style='margin-left:.5in'><span class=GramE>elevations</span> of these benchmarks above NAVD88 for 1 tide</pre><pre style='margin-left:.5in'><span class=GramE>gauge</span> in the <st1:State w:st="on"><st1:place w:st="on">District of Columbia</st1:place></st1:State> and 1 nearby tide gauge in</pre><pre style='margin-left:.5in'><st1:State w:st="on"><st1:place w:st="on">Maryland</st1:place></st1:State>.</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><span class=SpellE><i>Source_Information</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Source_Citation</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Citation_Information</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Originator:</i> National Oceanic Service</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Publication_Date</i></span><i>:</i> 2000</p> <p class=MsoNormal style='margin-left:.5in'><i>Title:</i></p> <p class=MsoNormal style='margin-left:.5in'>NOS Tide Estimation Data. Tide Tables 2000, High and Low Water Predictions, East Coast of North and South America including <st1:place w:st="on">Greenland</st1:place></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Geospatial_Data_Presentation_Form</i></span><i>:</i> document</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Source_Scale_Denominator</i></span><i>:</i> NA</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Type_of_Source_Media</i></span><i>:</i> paper report, whose tables contained latitude, longitude, and tide range.</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Source_Time_Period_of_Content</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Time_Period_Information</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Single_Date</i></span><i>/Time:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Calendar_Date</i></span><i>:</i> 2000</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Source_Currentness_Reference</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=GramE>publication</span> date</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Source_Contribution</i></span><i>:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>Horizontal <span class=GramE>location,</span> and spring high tide ranges for</pre><pre style='margin-left:.5in'><span class=GramE>more</span> than 9 tide gauges in and around the <st1:State w:st="on"><st1:place w:st="on">District of Columbia</st1:place></st1:State>.</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><span class=SpellE><i>Source_Information</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Source_Citation</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Citation_Information</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Originator:</i> <st1:country-region w:st="on"><st1:place w:st="on">U.S.</st1:place></st1:country-region> Environmental Protection Agency</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Publication_Date</i></span><i>:</i> 2006</p> <p class=MsoNormal style='margin-left:.5in'><i>Title:</i></p> <p class=MsoNormal style='margin-left:.5in'>Coastal Wetlands Data: <st1:State w:st="on"><st1:place w:st="on">District of Columbia</st1:place></st1:State></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Source_Scale_Denominator</i></span><i>:</i> 24,000</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Type_of_Source_Media</i></span><i>:</i> online</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Source_Time_Period_of_Content</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Time_Period_Information</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Single_Date</i></span><i>/Time:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Source_Contribution</i></span><i>:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>Horizontal location of upper and lower limits of tidal</pre><pre style='margin-left:.5in'><span class=GramE>wetlands</span>. See README_DC_Elevation.doc (distributed in the zip file with this</pre><pre style='margin-left:.5in'><span class=GramE>data</span> set), for directions on how to download the</pre><pre style='margin-left:.5in'>Coastal Wetlands <span class=GramE>Data .</span><span style='mso-spacerun:yes'>  </span>See also J.G. Titus and J. Wang, 2008. &quot;Maps of Lands Close to Sea Level along the <st1:PlaceName w:st="on">Middle</st1:PlaceName> <st1:PlaceName w:st="on">Atlantic</st1:PlaceName> <st1:PlaceType w:st="on">Coast</st1:PlaceType> of the <st1:country-region w:st="on"><st1:place w:st="on">United States</st1:place></st1:country-region>: An Elevation Data Set to Use While Waiting for LIDAR.&quot; Section 1.1 in: Background Documents Supporting Climate Change Science Program Synthesis and Assessment Product 4.1, J.G. Titus and E.M. Strange (<span class=GramE>eds</span>.). <span class=GramE>EPA 430R07004.</span> <st1:country-region w:st="on"><span class=GramE>U.S.</span></st1:country-region><span class=GramE> EPA, <st1:place w:st="on"><st1:City w:st="on">Washington</st1:City>, <st1:State w:st="on">DC</st1:State></st1:place>.</span></pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><span class=SpellE><i>Source_Information</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Source_Citation</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Citation_Information</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Originator:</i> <span class=SpellE>Proudman</span> Oceanographic Laboratory (POL)</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Publication_Date</i></span><i>:</i> 2000</p> <p class=MsoNormal style='margin-left:.5in'><i>Title:</i></p> <p class=MsoNormal style='margin-left:.5in'>Permanent Service for <st1:place w:st="on"><st1:PlaceName w:st="on">Mean</st1:PlaceName> <st1:PlaceType w:st="on">Sea</st1:PlaceType></st1:place> Level (PSMSL<span class=GramE>)-</span> Sea Level Rise Trend Data</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Other_Citation_Details</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'>The PSMSL is a member of the Federation of Astronomical and Geophysical Data Analysis Services (FAGS) established by the International Council of Scientific Unions (ICSU) (accessed December 2005).</p> <p class=MsoNormal style='margin-left:.5in'><i><span lang=DE style='mso-ansi-language: DE'>Online_Linkage:</span></i><span lang=DE style='mso-ansi-language:DE'> </span><a href="%3chttp://www.nbi.ac.uk/psmsl/datainfo/rlr.trends%3e" target=viewer><span lang=DE style='mso-ansi-language:DE'>&lt;http://www.nbi.ac.uk/psmsl/datainfo/rlr.trends&gt;</span></a><span style='mso-ansi-language:DE'> <span lang=DE><o:p></o:p></span></span></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Source_Scale_Denominator</i></span><i>:</i> 24,000</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Type_of_Source_Media</i></span><i>:</i> online</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Source_Time_Period_of_Content</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Time_Period_Information</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Single_Date</i></span><i>/Time:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Calendar_Date</i></span><i>:</i> unknown</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Source_Currentness_Reference</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=GramE>publication</span> date</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Source_Contribution</i></span><i>:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>Spatial location and estimates of</pre><pre style='margin-left:.5in'><span class=GramE>the</span> rate of sea level rise.</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><span class=SpellE><i>Source_Information</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Source_Citation</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Citation_Information</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Originator:</i> Henan Institute of <st1:place w:st="on"><st1:City w:st="on">Geography</st1:City>, <st1:country-region w:st="on">China</st1:country-region></st1:place></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Publication_Date</i></span><i>:</i> Unpublished Material</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Publication_Time</i></span><i>:</i> Unknown</p> <p class=MsoNormal style='margin-left:.5in'><i>Title:</i></p> <p class=MsoNormal style='margin-left:.5in'>Coastal Digital Line Graphs (DLG) created from USGS Digital Raster Graphs</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Source_Scale_Denominator</i></span><i>:</i> 24,000</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Type_of_Source_Media</i></span><i>:</i> Vector digital data</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Source_Contribution</i></span><i>:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original><span class=GramE>Spatial data and attributes.</span> Contours digitized from USGS 7.5 minute Digital Raster Graphics (<span class=SpellE>DRGs</span>). See Institute_of_Geography_DLG.doc, included in the zip <span class=GramE>file</span> with which this data is distributed, for a list of the 7.5-minute quads where we used the <st1:place w:st="on"><st1:PlaceType w:st="on">Institute</st1:PlaceType> of <st1:PlaceName w:st="on">Geography <span class=SpellE>DLG</span></st1:PlaceName></st1:place><span class=SpellE>'s</span>.</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><span class=SpellE><i>Process_Step</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Process_Description</i></span><i>:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>Process of Input Elevation Data</pre><pre style='margin-left:.5in'>Because there was no vertical datum information</pre><pre style='margin-left:.5in'><span class=GramE>associated</span> with the National Capital Planning</pre><pre style='margin-left:.5in'>Commission and District of Columbia Department of</pre><pre style='margin-left:.5in'>Public Works Rooftop Elevation and Ground Elevation</pre><pre style='margin-left:.5in'><span class=GramE>dataset</span>, we plotted the data against USGS contour lines</pre><pre style='margin-left:.5in'><span class=GramE>and</span> determined that vertical datum to be NAVD88. We</pre><pre style='margin-left:.5in'><span class=GramE>projected</span> the dataset into Albers projection and</pre><pre style='margin-left:.5in'><span class=GramE>converted</span> the elevation unit from meters to feet.</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><span class=SpellE><i>Process_Contact</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Information</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Person_Primary</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Person</i></span><i>:</i> <span class=SpellE>Jue</span> Wang</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Organization</i></span><i>:</i> GIS Practice, ICF Consulting, Inc.</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Position</i></span><i>:</i> Senior GIS Analyst</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Address</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Address_Type</i></span><i>:</i> mailing and physical address</p> <p class=MsoNormal style='margin-left:.5in'><i>Address:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original><st1:Street w:st="on"><st1:address w:st="on">9300 Lee Highway</st1:address></st1:Street></pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><i>City:</i> <st1:City w:st="on"><st1:place w:st="on">Fairfax</st1:place></st1:City></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>State_or_Province</i></span><i>:</i> VA</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Postal_Code</i></span><i>:</i> 22031</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Voice_Telephone</i></span><i>:</i> 703-218-2766</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Facsimile_Telephone</i></span><i>:</i> 703-934-3974</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Electronic_Mail_Address</i></span><i>:</i> jwang@icfconsulting.com</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Hours_of_Service</i></span><i>:</i> 9:30 - 5:30 EST</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Process_Step</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Process_Description</i></span><i>:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>Process of Tidal Record:<span style='mso-spacerun:yes'>  </span>Calculating the Elevation</pre><pre style='margin-left:.5in'><span class=GramE>of</span> Spring High Water Supplemental Contour</pre><pre style='margin-left:.5in'>1) Creation of Mean Tide Level Surface. National</pre><pre style='margin-left:.5in'>Oceanic Service (NOS) tide observation data, i.e., the</pre><pre style='margin-left:.5in'><span class=GramE>latitudes</span> and longitudes, the elevations of mean tide</pre><pre style='margin-left:.5in'><span class=GramE>level</span> (MTL) above mean lower low water (MLLW), the</pre><pre style='margin-left:.5in'><span class=GramE>elevations</span> of MLLW relative to several benchmarks, and</pre><pre style='margin-left:.5in'><span class=GramE>the</span> elevations above NAVD88 of these benchmarks of 2</pre><pre style='margin-left:.5in'><span class=GramE>tide</span> gages in the <st1:State w:st="on">District of Columbia</st1:State> and nearby <st1:State w:st="on"><st1:place w:st="on">Maryland</st1:place></st1:State> were</pre><pre style='margin-left: .5in'><span class=GramE>downloaded</span> from the NOS website. The elevations of mean</pre><pre style='margin-left:.5in'><span class=GramE>tide</span> level above NAVD88 were calculated and then</pre><pre style='margin-left:.5in'><span class=GramE>converted</span> to above NGVD29 using USGS VERTCON program. </pre><pre style='margin-left:.5in'>A point coverage was then created with this data and</pre><pre style='margin-left:.5in'><span class=GramE>projected</span> into Albers projection. Using the point</pre><pre style='margin-left:.5in'><span class=GramE>coverage</span> as a reference, artificial contour lines were</pre><pre style='margin-left:.5in'><span class=GramE>created</span> with consideration of shorelines via heads-up</pre><pre style='margin-left:.5in'><span class=GramE>digitizing</span> and then used to interpolate the mean tide</pre><pre style='margin-left:.5in'><span class=GramE>level</span> surface using a Triangular Irregular Network</pre><pre style='margin-left:.5in'>(TIN).<span style='mso-spacerun:yes'>  </span>As the tidal epoch used for the MTL data was</pre><pre style='margin-left:.5in'>1960-1978, a separate sea level rise rate surface was</pre><pre style='margin-left:.5in'><span class=GramE>created</span> by interpolating actual sea level rise data</pre><pre style='margin-left:.5in'>(<span class=GramE>trend</span>) from the <span class=SpellE>Proudman</span> Oceanographic Laboratory</pre><pre style='margin-left:.5in'><span class=GramE>website</span> and was used to adjust the mean tide level to</pre><pre style='margin-left:.5in'><span class=GramE>years</span> corresponding to other data sets, such as NWI</pre><pre style='margin-left:.5in'><span class=GramE>data</span>, so that the wetland boundary would represent</pre><pre style='margin-left:.5in'><span class=GramE>spring</span> high tide for the year the map imagery was</pre><pre style='margin-left:.5in'><span class=GramE>taken</span>.</pre><pre style='margin-left:.5in'>2) Creation of <st1:place w:st="on"><st1:PlaceType w:st="on">Spring</st1:PlaceType> <st1:PlaceName w:st="on">Tide</st1:PlaceName> <st1:PlaceType w:st="on">Range</st1:PlaceType></st1:place> Surface. From Table 2</pre><pre style='margin-left:.5in'><span class=GramE>of</span> &quot;Tide Tables 2000, High and Low Water Predictions,</pre><pre style='margin-left:.5in'>East Coast of North and <st1:place w:st="on">South America</st1:place> including</pre><pre style='margin-left:.5in'><st1:place w:st="on">Greenland</st1:place>&quot;, the latitudes, longitudes and spring high</pre><pre style='margin-left:.5in'><span class=GramE>tide</span> ranges of more than 150 tide gages were obtained</pre><pre style='margin-left:.5in'><span class=GramE>and</span> used to create a point coverage. Using the point</pre><pre style='margin-left:.5in'><span class=GramE>coverage</span> as a reference, artificial contour lines were</pre><pre style='margin-left:.5in'><span class=GramE>created</span> with consideration of shorelines and then used</pre><pre style='margin-left:.5in'><span class=GramE>to</span> interpolate the spring high tide range surface with</pre><pre style='margin-left:.5in'><span class=GramE>TIN method.</span></pre><pre style='margin-left:.5in'>3) Creation of a Spring High Water Level Surface. A</pre><pre style='margin-left:.5in'><span class=GramE>spring</span> high water level surface was created by adding</pre><pre style='margin-left:.5in'><span class=GramE>half</span> of spring tide range onto mean tide level surface.</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><span class=SpellE><i>Process_Contact</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Information</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Person_Primary</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Person</i></span><i>:</i> <span class=SpellE>Jue</span> Wang</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Organization</i></span><i>:</i> ICF Consulting, Inc., GIS Practice</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Position</i></span><i>:</i> Senior GIS Analyst</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Voice_Telephone</i></span><i>:</i> 703-218-2766</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Facsimile_Telephone</i></span><i>:</i> 703-934-3974</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Electronic_Mail_Address</i></span><i>:</i> jwang@icfconsulting.com</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Process_Step</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Process_Description</i></span><i>:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>Processing Tidal Wetlands:</pre><pre style='margin-left:.5in'>Calculating the Horizontal Position of Spring High</pre><pre style='margin-left:.5in'>Water Supplemental Contour</pre><pre style='margin-left: .5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>1.<span style='mso-spacerun:yes'>  </span>We identified the upper limit of tidal wetland by</pre><pre style='margin-left:.5in'><span class=GramE>extracting</span> the boundaries between tidal polygons</pre><pre style='margin-left:.5in'>(<span class=GramE>consisting</span> of tidal wetland and tidal open water) and</pre><pre style='margin-left:.5in'><span class=GramE>non-tidal</span> polygons (consisting of dry land, non-tidal</pre><pre style='margin-left:.5in'><span class=GramE>wetland</span>, and non-tidal open water).</pre><pre style='margin-left:.5in'>2) We used the upper and lower limits of tidal wetlands</pre><pre style='margin-left:.5in'><span class=GramE>to</span> generate supplemental contours. We assigned these</pre><pre style='margin-left:.5in'><span class=GramE>contours</span> elevations derived from spring high tide level</pre><pre style='margin-left:.5in'><span class=GramE>and</span> mean tide level surface grids respectively. The</pre><pre style='margin-left:.5in'><span class=GramE>upper</span> wetland boundary was used as a supplemental</pre><pre style='margin-left:.5in'><span class=GramE>contour</span>. The lower boundary was used for reporting the</pre><pre style='margin-left:.5in'><span class=GramE>area</span> of wetlands but not for elevations, because the</pre><pre style='margin-left:.5in'><span class=GramE>project</span> manager decided not to report wetland</pre><pre style='margin-left:.5in'><span class=GramE>elevations</span>.</pre><pre style='margin-left:.5in'>See also the metadata accompanying the &quot;Coastal Wetlands</pre><pre style='margin-left:.5in'>Data: <st1:State w:st="on"><st1:place w:st="on">District of Columbia</st1:place></st1:State>&quot; polygon dataset</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><span class=SpellE><i>Process_Contact</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Information</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Person_Primary</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Person</i></span><i>:</i> <span class=SpellE>Jue</span> Wang</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Organization</i></span><i>:</i> ICF Consulting, Inc., GIS Practice</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Position</i></span><i>:</i> Senior GIS Analyst</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Voice_Telephone</i></span><i>:</i> 703-218-2766</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Facsimile_Telephone</i></span><i>:</i> 703-934-3974</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Electronic_Mail_Address</i></span><i>:</i> jwang@icfconsulting.com</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Process_Step</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Process_Description</i></span><i>:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>Interpolation of Digital Elevation Model</pre><pre style='margin-left:.5in'>1) The study area was divided into lowland and upland.</pre><pre style='margin-left:.5in'>&quot;Tidal Wetlands&quot; represents the tidal wetlands as classified from the wetland layer.</pre><pre style='margin-left:.5in'>Lowland represents the area under the 1 meter contour</pre><pre style='margin-left:.5in'><span class=GramE>and</span> upland represents area from 1 meter contour line up</pre><pre style='margin-left:.5in'><span class=GramE>to</span> the political boundary of the <st1:State w:st="on"><st1:place w:st="on">District of Columbia</st1:place></st1:State>.</pre><pre style='margin-left:.5in'>We are not making the tidal wetland interpolations</pre><pre style='margin-left:.5in'><span class=GramE>available</span> in this dataset due to the lack of a</pre><pre style='margin-left:.5in'><span class=GramE>theoretical</span> justification for believing that</pre><pre style='margin-left:.5in'><span class=GramE>interpolation</span> to have any information content. (At</pre><pre style='margin-left:.5in'><span class=GramE>best</span>, the wetland elevation interpolations might be</pre><pre style='margin-left:.5in'><span class=GramE>used</span> for graphical representations of the impact of sea</pre><pre style='margin-left:.5in'><span class=GramE>level</span> rise.) We will retain a companion dataset with</pre><pre style='margin-left:.5in'><span class=GramE>elevations</span> stored as floating point double precision,</pre><pre style='margin-left:.5in'><span class=GramE>which</span> may be made available for the sole purpose of</pre><pre style='margin-left:.5in'><span class=GramE>evaluating</span> any graphical representations that use</pre><pre style='margin-left:.5in'><span class=GramE>wetland</span> elevations. We provide a gridded (and a</pre><pre style='margin-left:.5in'><span class=GramE>polygon</span>) wetland dataset so that the user can</pre><pre style='margin-left:.5in'><span class=GramE>distinguish</span> tidal wetlands from open water for cells</pre><pre style='margin-left:.5in'><span class=GramE>with</span> no data..</pre><pre style='margin-left:.5in'>2) The <span class=SpellE>DEMs</span> were interpolated with a predetermined</pre><pre style='margin-left:.5in'><span class=SpellE><span class=GramE>cellsize</span></span> of 30 meters for the lowland and upland areas</pre><pre style='margin-left:.5in'><span class=GramE>using</span> contour lines described in Process Step 1</pre><pre style='margin-left:.5in'>(&quot;Process of Input Elevation Data&quot;) and supplemental</pre><pre style='margin-left:.5in'><span class=GramE>contours</span> explained in process step 3. A common starting</pre><pre style='margin-left:.5in'><span class=GramE>coordinate</span> was set for all three DEM interpolation</pre><pre style='margin-left:.5in'><span class=GramE>processes</span> to ensure alignment of the separate layers</pre><pre style='margin-left:.5in'><span class=GramE>after</span> processing. The minimum and maximum limits were</pre><pre style='margin-left:.5in'><span class=GramE>set</span> for each process according to the input elevation</pre><pre style='margin-left:.5in'><span class=GramE>data</span> to ensure the resulting elevations were in</pre><pre style='margin-left:.5in'><span class=GramE>accordance</span> with the input data. See &quot;first contour</pre><pre style='margin-left:.5in'><span class=GramE>truncating</span>&quot; (#4) below. The iteration was</pre><pre style='margin-left:.5in'><span class=GramE>set</span> to 40, the horizontal standard error tolerance was</pre><pre style='margin-left:.5in'><span class=GramE>set</span> to 2 to minimize the depression caused by</pre><pre style='margin-left:.5in'><span class=GramE>inappropriate</span> tend calculation, and the drainage</pre><pre style='margin-left:.5in'><span class=GramE>enforcement</span> option was turned on to remove isolated</pre><pre style='margin-left:.5in'><span class=GramE>depressions</span>.</pre><pre style='margin-left:.5in'>The following represents the options used in TOPOGRID:</pre><pre style='margin-left:.5in'><span class=SpellE><span class=GramE>topogrid</span></span> <span class=SpellE>dem_up_ft</span> 30</pre><pre style='margin-left:.5in'><span class=GramE>contour</span> <span class=SpellE>dlg_mtr_alb</span> <span class=SpellE>elev_feet</span></pre><pre style='margin-left:.5in'><span class=SpellE><span class=GramE>xyzlimits</span></span> 1610096.5<span style='mso-spacerun:yes'>  </span># 1907771 # 3.2809</pre><pre style='margin-left:.5in'><span class=GramE>boundary</span> <span class=SpellE>topo_bnd_up</span></pre><pre style='margin-left:.5in'><span class=GramE>iterations</span> 40</pre><pre style='margin-left:.5in'><span class=GramE>tolerances</span> # 2</pre><pre style='margin-left:.5in'><span class=GramE>enforce</span> on</pre><pre style='margin-left:.5in'><span class=GramE>end</span></pre><pre style='margin-left:.5in'>3) The interpolated <span class=SpellE>DEMs</span> were displayed against input</pre><pre style='margin-left:.5in'><span class=GramE>elevation</span> data and visually checked. These visual</pre><pre style='margin-left:.5in'><span class=GramE>checks</span> showed gross errors, but not necessarily</pre><pre style='margin-left:.5in'><span class=GramE>errors</span> in which the amount of low land is over- or</pre><pre style='margin-left:.5in'><span class=GramE>underestimated</span> by 10-40 percent (additionally, see Data</pre><pre style='margin-left:.5in'><span class=GramE>Quality, Positional Accuracy section).</span> If obvious</pre><pre style='margin-left:.5in'><span class=GramE>errors</span> such as artificial depressions occurred,</pre><pre style='margin-left:.5in'><span class=GramE>supplemental</span> elevation lines were added by heads-up</pre><pre style='margin-left:.5in'><span class=GramE>digitizing</span> to the input contour lines and the</pre><pre style='margin-left:.5in'><span class=GramE>interpolation</span> was repeated.</pre><pre style='margin-left:.5in'>4) First-contour truncating. As a result of the comparison </pre><pre style='margin-left:.5in'><span class=GramE>between</span> the initial DEM and the source contours for 11 </pre><pre style='margin-left:.5in'>USGS quadrangles (see vertical accuracy report), we </pre><pre style='margin-left:.5in'><span class=GramE>decided</span> to reset the DEM values to coincide with </pre><pre style='margin-left:.5in'><span class=GramE>source</span> contours. Our general approach was</pre><pre style='margin-left:.5in'><span class=GramE>that</span> whenever TOPOGRID calculated a value equal or</pre><pre style='margin-left:.5in'><span class=GramE>greater</span> than the first contour within the &quot;lowland&quot;, we</pre><pre style='margin-left:.5in'><span class=GramE>reset</span> the value to 0.001 lower than the first contour</pre><pre style='margin-left:.5in'><span class=GramE>and</span> whenever TOPOGRID calculated a value equal or less</pre><pre style='margin-left:.5in'><span class=GramE>than</span> the first contour within the upland, we reset the</pre><pre style='margin-left:.5in'><span class=GramE>value</span> to 0.001 greater than the first contour. Given</pre><pre style='margin-left:.5in'><span class=GramE>the</span> rounding of this integer dataset, all such values</pre><pre style='margin-left:.5in'><span class=GramE>are</span> effectively rounded to the bounding contour value</pre><pre style='margin-left:.5in'><span class=GramE>between</span> upland and lowland. Although this approach</pre><pre style='margin-left:.5in'><span class=GramE>leaves</span> us with some plateaus, we have fewer plateaus</pre><pre style='margin-left:.5in'><span class=GramE>than</span> we had when we did not divide the data; and</pre><pre style='margin-left:.5in'><span class=GramE>dividing</span> the data left us with fewer cases of upland</pre><pre style='margin-left:.5in'><span class=GramE>values</span> being outside of their appropriate ranges.</pre><pre style='margin-left:.5in'>5) To be consistent with the other states, we converted</pre><pre style='margin-left:.5in'><span class=GramE>the</span> <span class=SpellE>DEMs</span> into NGVD29. We generated <span class=GramE>a point</span> coverage</pre><pre style='margin-left:.5in'><span class=GramE>with</span> 130 randomly distributed points over the entire</pre><pre style='margin-left:.5in'><span class=GramE>study</span> area and calculated the difference values between</pre><pre style='margin-left:.5in'><span class=GramE>the</span> two data sets for each point using National Geodetic</pre><pre style='margin-left:.5in'>Survey North American Vertical Datum Conversion Utility</pre><pre style='margin-left:.5in'><span class=GramE>(VERTCON) program.</span> We projected the coverage into</pre><pre style='margin-left:.5in'>Albers projection and interpolated a grid of 30 meter</pre><pre style='margin-left:.5in'><span class=GramE>resolution</span> by TOPOGRID.<span style='mso-spacerun:yes'>  </span>We then used this grid to</pre><pre style='margin-left:.5in'><span class=GramE>convert</span> the DEM from NAVD88 to NGVD29.</pre><pre style='margin-left:.5in'>6) The <span class=SpellE>DEMs</span> <span class=GramE>of<span style='mso-spacerun:yes'>  </span>upland</span> and lowland were eventually</pre><pre style='margin-left:.5in'><span class=GramE>merged</span> into the final DEM with the MERGE function</pre><pre style='margin-left:.5in'><span class=GramE>within</span> the ESRI GRID module.</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><span class=SpellE><i>Process_Contact</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Information</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Person_Primary</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Person</i></span><i>:</i> <span class=SpellE>Jue</span> Wang</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Organization</i></span><i>:</i> GIS Practice, ICF Consulting, Inc.</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Position</i></span><i>:</i> Senior GIS Analyst</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Voice_Telephone</i></span><i>:</i> 703-218-2766</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Facsimile_Telephone</i></span><i>:</i> 703-934-3974</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Electronic_Mail_Address</i></span><i>:</i> jwang@icfconsulting.com</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Cloud_Cover</i></span><i>:</i> NA</p> <p class=MsoNormal><a href="#Top">Back to Top</a> <a name="Spatial_Data_Organization_Information"></a></p> <div class=MsoNormal align=center style='text-align:center'><span style='mso-bookmark:Spatial_Data_Organization_Information'> <hr size=2 width="100%" align=center> </span></div> <span style='font-size:12.0pt;font-family:"Times New Roman";mso-fareast-font-family: "Times New Roman";mso-ansi-language:EN-US;mso-fareast-language:EN-US; mso-bidi-language:AR-SA'><span style='mso-bookmark:Spatial_Data_Organization_Information'></span></span> <p class=MsoNormal><span class=SpellE><i>Spatial_Data_Organization_Information</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Direct_Spatial_Reference_Method</i></span><i>:</i> Raster</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Raster_Object_Information</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Raster_Object_Type</i></span><i>:</i> Grid Cell</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Row_Count</i></span><i>:</i> 1052</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Column_Count</i></span><i>:</i> 793</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Vertical_Count</i></span><i>:</i> 1</p> <p class=MsoNormal><a href="#Top">Back to Top</a> <a name="Spatial_Reference_Information"></a></p> <div class=MsoNormal align=center style='text-align:center'><span style='mso-bookmark:Spatial_Reference_Information'> <hr size=2 width="100%" align=center> </span></div> <span style='font-size:12.0pt;font-family:"Times New Roman";mso-fareast-font-family: "Times New Roman";mso-ansi-language:EN-US;mso-fareast-language:EN-US; mso-bidi-language:AR-SA'><span style='mso-bookmark:Spatial_Reference_Information'></span></span> <p class=MsoNormal><span class=SpellE><i>Spatial_Reference_Information</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Horizontal_Coordinate_System_Definition</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Planar:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Map_Projection</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Map_Projection_Name</i></span><i>:</i> Albers Conical Equal Area</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Albers_Conical_Equal_Area</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Standard_Parallel</i></span><i>:</i> 29.500000</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Standard_Parallel</i></span><i>:</i> 45.500000</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Longitude_of_Central_Meridian</i></span><i>:</i> -96.000000</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Latitude_of_Projection_Origin</i></span><i>:</i> 23.000000</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>False_Easting</i></span><i>:</i> 0.000000</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>False_Northing</i></span><i>:</i> 0.000000</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Planar_Coordinate_Information</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Planar_Coordinate_Encoding_Method</i></span><i>:</i> row and column</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Coordinate_Representation</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Abscissa_Resolution</i></span><i>:</i> 30.000000</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Ordinate_Resolution</i></span><i>:</i> 30.000000</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Planar_Distance_Units</i></span><i>:</i> meters</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Geodetic_Model</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Horizontal_Datum_Name</i></span><i>:</i> North American Datum of 1983</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Ellipsoid_Name</i></span><i>:</i> Geodetic Reference System 80</p> <p class=MsoNormal style='margin-left:.5in'><i>Semi-<span class=SpellE>major_Axis</span>:</i> 6378137.000000</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Denominator_of_Flattening_Ratio</i></span><i>:</i> 298.257222</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Vertical_Coordinate_System_Definition</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Altitude_System_Definition</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Altitude_Datum_Name</i></span><i>:</i> SHW</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Altitude_Resolution</i></span><i>:</i> 1 cm</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Altitude_Distance_Units</i></span><i>:</i> cm</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Altitude_Encoding_Method</i></span><i>:</i> Explicit elevation coordinate included with horizontal coordinates</p> <p class=MsoNormal><a href="#Top">Back to Top</a> <a name="Entity_and_Attribute_Information"></a></p> <div class=MsoNormal align=center style='text-align:center'><span style='mso-bookmark:Entity_and_Attribute_Information'> <hr size=2 width="100%" align=center> </span></div> <span style='font-size:12.0pt;font-family:"Times New Roman";mso-fareast-font-family: "Times New Roman";mso-ansi-language:EN-US;mso-fareast-language:EN-US; mso-bidi-language:AR-SA'><span style='mso-bookmark:Entity_and_Attribute_Information'></span></span> <p class=MsoNormal><span class=SpellE><i>Entity_and_Attribute_Information</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Detailed_Description</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><i><span lang=DE style='mso-ansi-language: DE'>Entity_Type:</span></i><span lang=DE style='mso-ansi-language:DE'><o:p></o:p></span></p> <p class=MsoNormal style='margin-left:.5in'><i><span lang=DE style='mso-ansi-language: DE'>Entity_Type_Label:</span></i><span lang=DE style='mso-ansi-language:DE'> dc_dem_sph_cm.vat<o:p></o:p></span></p> <p class=MsoNormal style='margin-left:.5in'><i><span lang=DE style='mso-ansi-language: DE'>Entity_Type_Definition:</span></i><span lang=DE style='mso-ansi-language: DE'><o:p></o:p></span></p> <p class=MsoNormal style='margin-left:.5in'><span lang=DE style='mso-ansi-language: DE'>DEM<o:p></o:p></span></p> <p class=MsoNormal style='margin-left:.5in'><i>Attribute:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Attribute_Label</i></span><i>:</i> <span class=SpellE>Rowid</span></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Attribute_Definition</i></span><i>:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original><span class=GramE>Internal feature number.</span></pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><span class=SpellE><i>Attribute_Definition_Source</i></span><i>:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>ESRI</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><span class=SpellE><i>Attribute_Domain_Values</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Unrepresentable_Domain</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=GramE>Sequential unique whole numbers that are automatically generated.</span></p> <p class=MsoNormal style='margin-left:.5in'><i>Attribute:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Attribute_Label</i></span><i>:</i> VALUE</p> <p class=MsoNormal style='margin-left:.5in'><i>Attribute:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Attribute_Label</i></span><i>:</i> Value</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Attribute_Definition</i></span><i>:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>Elevation</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><span class=SpellE><i>Attribute_Definition_Source</i></span><i>:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>Interpolated from input data sets</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><span class=SpellE><i>Attribute_Value_Accuracy_Information</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Attribute_Value_Accuracy</i></span><i>:</i> 1 cm</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Attribute_Value_Accuracy_Explanation</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'>Interpolated from source data sets and rounded to nearest 1 cm</p> <p class=MsoNormal style='margin-left:.5in'><i>Attribute:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Attribute_Label</i></span><i>:</i> COUNT</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Attribute_Definition</i></span><i>:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>Count of cells with common elevation</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><span class=SpellE><i>Attribute_Definition_Source</i></span><i>:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>ESRI</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><span class=SpellE><i>Overview_Description</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Entity_and_Attribute_Overview</i></span><i>:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>Elevations generated from input data sets (contours and</pre><pre style='margin-left:.5in'><span class=GramE>spot</span> elevations) and interpolated into a raster DEM and</pre><pre style='margin-left:.5in'><span class=GramE>rounded</span> to nearest cm.</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><span class=SpellE><i>Entity_and_Attribute_Detail_Citation</i></span><i>:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>See process</pre><pre style='margin-left:.5in'><span class=GramE>steps</span>.</pre> <p class=MsoNormal><script> fix(original) </script><a href="#Top">Back to Top</a> <a name=271383040></a></p> <div class=MsoNormal align=center style='text-align:center'><span style='mso-bookmark:271383040'> <hr size=2 width="100%" align=center> </span></div> <span style='font-size:12.0pt;font-family:"Times New Roman";mso-fareast-font-family: "Times New Roman";mso-ansi-language:EN-US;mso-fareast-language:EN-US; mso-bidi-language:AR-SA'><span style='mso-bookmark:271383040'></span></span> <p class=MsoNormal><span class=SpellE><i>Distribution_Information</i></span><i>:</i> </p> <p class=MsoNormal style='margin-left:.5in'><i>Distributor:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Information</i></span><i>: </i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Organization_Primary</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Organization</i></span><i>:</i> US Environmental Protection Agency, Climate Change Division</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Address</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Address_Type</i></span><i>:</i> mailing address</p> <p class=MsoNormal style='margin-left:.5in'><i>Address:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>USEPA (6207-J)</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><i>Address:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original><st1:Street w:st="on"><st1:address w:st="on">1200 Pennsylvania Ave. NW</st1:address></st1:Street></pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><i>City:</i> <st1:State w:st="on"><st1:place w:st="on">Washington</st1:place></st1:State></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>State_or_Province</i></span><i>:</i> DC</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Postal_Code</i></span><i>:</i> 20460</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Voice_Telephone</i></span><i>:</i> 202-343-9990</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Facsimile_Telephone</i></span><i>:</i> 202-343-2338</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Electronic_Mail_Address</i></span><i>:</i> climatechange@epamail.epa.gov</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Resource_Description</i></span><i>:</i> The dataset is being distributed by the US Environmental Protection Agency.</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Distribution_Liability</i></span><i>:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>Although this data was created under the direction of</pre><pre style='margin-left:.5in'><span class=GramE>the</span> EPA, no warranty expressed or implied is made</pre><pre style='margin-left:.5in'><span class=GramE>regarding</span> the accuracy or utility of the data. Neither</pre><pre style='margin-left:.5in'><span class=GramE>EPA</span> nor the data developers shall be held liable for</pre><pre style='margin-left:.5in'><span class=GramE>any</span> use of the data and information</pre><pre style='margin-left:.5in'><span class=GramE>described</span> and/or contained herein.</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><span class=SpellE><i>Standard_Order_Process</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Digital_Form</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Digital_Transfer_Information</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Transfer_Size</i></span><i>:</i> 0.511</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Technical_Prerequisites</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=GramE>Requires software capable of displaying raster data.</span></p> <p class=MsoNormal><a href="#Top">Back to Top</a> <a name="Metadata_Reference_Information"></a></p> <div class=MsoNormal align=center style='text-align:center'><span style='mso-bookmark:Metadata_Reference_Information'> <hr size=2 width="100%" align=center> </span></div> <span style='font-size:12.0pt;font-family:"Times New Roman";mso-fareast-font-family: "Times New Roman";mso-ansi-language:EN-US;mso-fareast-language:EN-US; mso-bidi-language:AR-SA'><span style='mso-bookmark:Metadata_Reference_Information'></span></span> <p class=MsoNormal><span class=SpellE><i>Metadata_Reference_Information</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Metadata_Date</i></span><i>:</i> 20080902</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Metadata_Contact</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Information</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Person_Primary</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Person</i></span><i>:</i> Russ Jones, Jim Titus, and <span class=SpellE>Jue</span> Wang</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Organization</i></span><i>:</i> Stratus Consulting Inc. (Jones)</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Position</i></span><i>:</i> Managing Analyst (Jones)</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Address</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Address_Type</i></span><i>:</i> mailing and physical address</p> <p class=MsoNormal style='margin-left:.5in'><i>Address:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original><st1:Street w:st="on"><st1:address w:st="on">1881 9th St. Suite 201</st1:address></st1:Street> (Jones)</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><i>City:</i> <st1:City w:st="on"><st1:place w:st="on">Boulder</st1:place></st1:City></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>State_or_Province</i></span><i>:</i> CO</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Postal_Code</i></span><i>:</i> 80306</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Voice_Telephone</i></span><i>:</i> 303-381-8000 (Jones)</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Voice_Telephone</i></span><i>:</i> 202-343-9307 (Titus)</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Facsimile_Telephone</i></span><i>:</i> 303-381-8200 (Jones)</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Electronic_Mail_Address</i></span><i>:</i> rjones@stratusconsulting.com</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Contact_Electronic_Mail_Address</i></span><i>:</i> Titus.Jim@epamail.epa.gov</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Hours_of_Service</i></span><i>:</i> 9:00 - 5:00 MST</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Metadata_Standard_Name</i></span><i>:</i> FGDC Content Standards for Digital Geospatial Metadata</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Metadata_Standard_Version</i></span><i>:</i> FGDC-STD-001-1998</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Metadata_Time_Convention</i></span><i>:</i> local time</p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Metadata_Extensions</i></span><i>:</i></p> <p class=MsoNormal style='margin-left:.5in'><i><span lang=DE style='mso-ansi-language: DE'>Online_Linkage:</span></i><span lang=DE style='mso-ansi-language:DE'> <a href="http://maps.risingsea.net/data/DC_elevation_metadata.html"><span lang=EN-US style='color:windowtext;mso-ansi-language:EN-US;text-decoration: none;text-underline:none'><span style='mso-field-code:" HYPERLINK \0022http\:\/\/www\.esri\.com\/metadata\/esriprof80\.html\0022 \\t \0022viewer\0022 "'><u><span style='color:blue'>http://www.esri.com/metadata/esriprof80.html</span></u></span></span></a> <o:p></o:p></span></p> <p class=MsoNormal style='margin-left:.5in'><span class=SpellE><i>Profile_Name</i></span><i>:</i> ESRI Metadata Profile</p> <p class=MsoNormal><a href="#Top">Back to Top</a> </p> </div> </body> </html>