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="NY_elevation_metadata_files/filelist.xml"> <link rel=Edit-Time-Data href="NY_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>New York 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>2</o:Revision> <o:TotalTime>1</o:TotalTime> <o:Created>2009-04-17T11:37:00Z</o:Created> <o:LastSaved>2009-04-17T11:37:00Z</o:LastSaved> <o:Pages>1</o:Pages> <o:Words>6835</o:Words> <o:Characters>38965</o:Characters> <o:Company>EPA</o:Company> <o:Lines>324</o:Lines> <o:Paragraphs>91</o:Paragraphs> <o:CharactersWithSpaces>45709</o:CharactersWithSpaces> <o:Version>11.9999</o:Version> </o:DocumentProperties> </xml><![endif]--><!--[if gte mso 9]><xml> <w:WordDocument> <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 <st1:country-region w:st="on"><st1:place w:st="on">United States</st1:place></st1:country-region>.&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">Identification_Information</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">Data_Quality_Information</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">Spatial_Data_Organization_Information</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">Spatial_Reference_Information</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">Entity_and_Attribute_Information</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="#33898336">Distribution_Information </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">Metadata_Reference_Information</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><i>Identification_Information:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Citation:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Citation_Information:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Originator:</i> US Environmental Protection Agency</p> <p class=MsoNormal style='margin-left:.5in'><i>Publication_Date:</i> February 2008</p> <p class=MsoNormal style='margin-left:.5in'><i>Title:</i></p> <p class=MsoNormal style='margin-left:.5in'>New York 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'><i>Geospatial_Data_Presentation_Form:</i> raster digital data</p> <p class=MsoNormal style='margin-left:.5in'><i>Other_Citation_Details:</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'><i>Larger_Work_Citation:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Citation_Information:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Originator:</i> US Environmental Protection Agency</p> <p class=MsoNormal style='margin-left:.5in'><i>Publication_Date:</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'><i>Other_Citation_Details:</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 (eds.)]. 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.</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>Coastal <st1:State w:st="on"><st1:place w:st="on">New York</st1:place></st1:State> Digital Elevation Model (Environmental</pre><pre style='margin-left:.5in'>Systems Research Institute [ESRI] Grid format)</pre><pre style='margin-left:.5in'>represents an elevation map of the <st1:State w:st="on"><st1:place w:st="on">New York</st1:place></st1:State> coastal</pre><pre style='margin-left: .5in'>zone created for the purposes of analyzing</pre><pre style='margin-left: .5in'>vulnerability to coastal flooding and rising sea level.</pre><pre style='margin-left:.5in'>The domain of the data set extends from the upper tidal</pre><pre style='margin-left:.5in'>wetland boundary up to the 40 foot NGVD29 contour, but</pre><pre style='margin-left:.5in'>the primary focus of the analytical approach and</pre><pre style='margin-left:.5in'>quality control has focused on land below the 10-foot</pre><pre style='margin-left:.5in'>contour. This data set has been derived from several</pre><pre style='margin-left:.5in'>sources of elevation data, including <st1:country-region w:st="on"><st1:place w:st="on">United States</st1:place></st1:country-region></pre><pre style='margin-left:.5in'>Geological Survey (USGS) 1:24,000 Digital Line Graphs</pre><pre style='margin-left:.5in'>(DLG), DLG's created by Henan Institute</pre><pre style='margin-left:.5in'>of Geography from USGS 1:24,000 Digital Raster Graphics,</pre><pre style='margin-left:.5in'>US. Corps of Engineer Spot Elevation data, and Monmouth</pre><pre style='margin-left:.5in'>County elevation data. In addition, the analysis</pre><pre style='margin-left:.5in'>created a supplemental contour representing the</pre><pre style='margin-left:.5in'>elevation of spring high water (SHW), which</pre><pre style='margin-left:.5in'>ranges from<span style='mso-spacerun:yes'>  </span>1.1 to 5.3 feet above NGVD29 in <st1:State w:st="on"><st1:place w:st="on">New York</st1:place></st1:State>. We</pre><pre style='margin-left:.5in'>defined the horizontal position of that contour by</pre><pre style='margin-left:.5in'>extracting the inland limit of<span style='mso-spacerun:yes'>  </span>the tidal wetland</pre><pre style='margin-left:.5in'>polygons in a separate Coastal Wetlands data set we</pre><pre style='margin-left:.5in'>created for this project (based on the National</pre><pre style='margin-left:.5in'>Wetlands Inventory and state wetlands data). . We</pre><pre style='margin-left:.5in'>defined the vertical position of the supplemental</pre><pre style='margin-left:.5in'>contour by creating a &quot;tidal elevation surface&quot; using</pre><pre style='margin-left:.5in'>the National Ocean Service's (NOS) estimated tide</pre><pre style='margin-left:.5in'>ranges, NOS estimated sea level trends, NOS published</pre><pre style='margin-left:.5in'>benchmark sheets, and the National Geodetic Survey</pre><pre style='margin-left:.5in'>North American Vertical Datum Conversion Utility</pre><pre style='margin-left:.5in'>(VERTCON) program to convert the Mean Tide Level (MTL)</pre><pre style='margin-left:.5in'>above NAVD88 to NGVD29. All elevation information was</pre><pre style='margin-left:.5in'>converted to a common vertical reference, usually</pre><pre style='margin-left:.5in'>NGVD29, and the DEM was generated from that input data</pre><pre style='margin-left:.5in'>using ESRI's interpolation algorithm TOPOGRID (within</pre><pre style='margin-left:.5in'>ArcGIS workstation GRID extension). We converted the absolute elevation estimates (usually NGVD29) into elevations relative to SHW using the &quot;tidal elevation surface.&quot; For purposes of this data set,</pre><pre style='margin-left:.5in'>SHW is the upper boundary of tidal wetlands (including</pre><pre style='margin-left:.5in'>vegetated wetlands and intertidal beaches). Elevation</pre><pre style='margin-left:.5in'>is expressed in cm.</pre><pre style='margin-left:.5in'>The zip file associated with this data set should</pre><pre style='margin-left:.5in'>include:</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>1.<span style='mso-spacerun:yes'>   </span>README_NY_Elevation.doc, which provides a brief overview of the</pre><pre style='margin-left:.5in'>relationship between this dataset and related data</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>2.<span style='mso-spacerun:yes'>   </span>InterpolationMethods_MEMO.doc</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>3.<span style='mso-spacerun:yes'>   </span>NY_Data_Quality.jpg</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>4.<span style='mso-spacerun:yes'>   </span>DEM_LidarComparisonTable.doc</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></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'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>6.<span style='mso-spacerun:yes'>   </span>Institute_of_Geography_DLG.xls</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>7.<span style='mso-spacerun:yes'>  </span>Titus_and_Wang_2008.pdf</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>However, to speed download, in the online versions, (2) and (9) (which are associated with all of the states) may have been removed</pre><pre style='margin-left:.5in'>and included in a file called  Common_supplemental_metadata.zip </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 New York Digital Elevation Model provides a base</pre><pre style='margin-left:.5in'>map layer for assessing the possible influences of</pre><pre style='margin-left:.5in'>potential sea level rise on coast regions. We recommend against using this data to create maps with scales greater than 1:100,000, regardless of the level of vertical precision portrayed.<span style='mso-spacerun:yes'>  </span>Moreover, if the purpose of using this data is to create graphical depictions of risk with contour intervals of 50-100 cm, we recommend a considerably smaller scale unless the audience is likely to understand the limitations of the data.</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><i>Supplemental_Information:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>Elevations relative to year 2000.</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><i>Description:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Purpose:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>The New York Digital Elevation Model provides a base</pre><pre style='margin-left:.5in'>map layer for assessing the possible influences of</pre><pre style='margin-left:.5in'>potential sea level rise on coast regions. We recommend against using this data to create maps with scales greater than 1:100,000, regardless of the level of vertical precision portrayed.<span style='mso-spacerun:yes'>  </span>Moreover, if the purpose of using this data is to create graphical depictions of risk with contour intervals of 50-100 cm, we recommend a considerably smaller scale unless the audience is likely to understand the limitations of the data.</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><i>Description:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Purpose:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>The New York Digital Elevation Model provides a base</pre><pre style='margin-left:.5in'>map layer for assessing the possible influences of</pre><pre style='margin-left:.5in'>potential sea level rise on coast regions. We recommend against using this data to create maps with scales greater than 1:100,000, regardless of the level of vertical precision portrayed.<span style='mso-spacerun:yes'>  </span>Moreover, if the purpose of using this data is to create graphical depictions of risk with contour intervals of 50-100 cm, we recommend a considerably smaller scale unless the audience is likely to understand the limitations of the data.</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><i>Time_Period_of_Content:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Time_Period_Information:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Single_Date/Time:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Calendar_Date:</i> 2000</p> <p class=MsoNormal style='margin-left:.5in'><i>Currentness_Reference:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>ground 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'><i>Maintenance_and_Update_Frequency:</i> None planned</p> <p class=MsoNormal style='margin-left:.5in'><i>Spatial_Domain:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Bounding_Coordinates:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>West_Bounding_Coordinate:</i> -74.490310</p> <p class=MsoNormal style='margin-left:.5in'><i>East_Bounding_Coordinate:</i> -70.870849</p> <p class=MsoNormal style='margin-left:.5in'><i>North_Bounding_Coordinate:</i> 42.169455</p> <p class=MsoNormal style='margin-left:.5in'><i>South_Bounding_Coordinate:</i> 39.904846</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'><i>Theme_Keyword_Thesaurus:</i> General</p> <p class=MsoNormal style='margin-left:.5in'><i>Theme_Keyword:</i> <st1:State w:st="on"><st1:place w:st="on">New York</st1:place></st1:State> Elevation</p> <p class=MsoNormal style='margin-left:.5in'><i>Theme_Keyword:</i> DEM</p> <p class=MsoNormal style='margin-left:.5in'><i>Theme_Keyword:</i> Coastal Elevation</p> <p class=MsoNormal style='margin-left:.5in'><i>Place:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Place_Keyword:</i> NY</p> <p class=MsoNormal style='margin-left:.5in'><i>Access_Constraints:</i> None</p> <p class=MsoNormal style='margin-left:.5in'><i>Use_Constraints:</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><i>Point_of_Contact:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Information:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Person_Primary:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Person:</i> James G. Titus</p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Organization:</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'><i>Contact_Position:</i> Project Manager</p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Address:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Address_Type:</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>Mailcode 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'><i>State_or_Province:</i> DC</p> <p class=MsoNormal style='margin-left:.5in'><i>Postal_Code:</i> 20460</p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Voice_Telephone:</i> 202-343-9307</p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Facsimile_Telephone:</i> 202-343-2338</p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Electronic_Mail_Address:</i> Titus.Jim@epamail.epa.gov</p> <p class=MsoNormal style='margin-left:.5in'><i>Hours_of_Service:</i> 9:00 - 6:00 Eastern</p> <p class=MsoNormal style='margin-left:.5in'><i>Data_Set_Credit:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>Jue Wang, GIS Practice, ICF</pre><pre style='margin-left:.5in'>Consulting, Inc.</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><i>Native_Data_Set_Environment:</i></p> <p class=MsoNormal style='margin-left:.5in'>Microsoft Windows XP Version 5.1 (Build 2600) Service Pack 2; ESRI ArcCatalog 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><i>Data_Quality_Information:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Attribute_Accuracy:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Attribute_Accuracy_Report:</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. The accuracy of this data set generally corresponds to the source data used in the layer development. See &quot;NY_Data_Quality.jpg&quot; for<span style='mso-spacerun:yes'>  </span>an index of the source data used (that 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 generated using the interpolation function &quot;TOPOGRID&quot; within the ESRI GRID module. TOPOGRID uses input elevation data such as contours and elevation point data along with supplemental information such as stream networks, lakes (of known elevation), and bounding areas to generate a hydrologically-correct DEM. Each state DEM was generated using TOPOGRID but the specific parameters were unique to the data sets available 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'>TOPOGRID Plateau Problem. The TOPOGRID function generates disproportionately large areas with the same value of the input contour lines, e.g., if we have 5 and 10 foot contour lines, there would be substantially more areas with values between 4 to 6 and 9 to 11, than 6 to 9 feet. At the upper tips of narrow valleys, the cell values tend to be the same as the bounding contours so the valleys become plateaus. The TOPOGRID function within the ESRI GRID module tends to calculate a trend from neighboring contour lines. As a result, TOPOGRID frequently creates areas of erroneous depressions on the plains adjacent to steep slopes, often substantially below the contours between which those depressions lay. It also creates plateaus along contours, which can be problematic because they overstate the amount of land barely above the wetlands and right at the first contour, while understating the amount of land halfway between the wetlands and the first contour. To address these problems, we processed the areas above and below the first contour separately. However, this caused another problem. In narrow valleys in the area below the first contour, the output DEM values were similar or identical to those of the bounding contour lines due to the lack of elevation information that TOPOGRID needs to calculate trend. The most problematic regions occurred where there was a stream valley below the first contour (e.g. between two parallel 5 foot contours), neither open water nor tidal wetlands along most of the length of the valley, but open water or tidal wetlands at one end of the valley (e.g. a typical non-tidal stream flowing into tidal waters). In some cases, the trend from the wetlands or open water at the mouth toward the bounding first contour would provide values even higher than that first contour farther up the valley. And in general, TOPOGRID would be more likely to assume a flat area between the contours, than to characterize it as a valley--except for when stream data showed a stream in the correct location.</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>Evaluation of other interpolation methods. </pre><pre style='margin-left:.5in'>Several interpolation methods were evaluated before the TOPOGRID function was selected. Specifically, Spline, Inverse Distance Weighting (IDW), and Triangulated Irregular Network (TIN) methods were evaluated and compared to the TOPOGRID function. Statistics and graphical examples of cross sections specific to each interpolation method are presented in the accompanying &quot;InterpolationMethods_MEMO.doc&quot; memo included in the zip file associated with this data set.</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><i>Attribute_Accuracy:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Quantitative_Attribute_Accuracy_Assessment:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Attribute_Accuracy_Explanation:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>An accuracy assessment was made between the source<span style='mso-spacerun:yes'>  </span>DLG's and the DEM for a select number of quads. See &quot;DEM_Comparison_with_DLG_11_quads.xls&quot;<span style='mso-spacerun:yes'>  </span>which accompanies this data set in the zip file.</pre><pre style='margin-left:.5in'>An additional assessment was made between the DEM and lidar data where it was available in <st1:State w:st="on">Maryland</st1:State> and <st1:State w:st="on"><st1:place w:st="on">North Carolina</st1:place></st1:State>. The results can be found in the &quot;DEM_LidarComparisonTable.doc&quot; that accompanied this data set in the zip file.</pre><pre style='margin-left:.5in'>See the sections on Positional Accuracy (Horizontal and Vertical).</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><i>Logical_Consistency_Report:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>Refer to the draft technical report that documents this</pre><pre style='margin-left:.5in'>study for information on the<span style='mso-spacerun:yes'>  </span>procedures used to</pre><pre style='margin-left:.5in'>develop this layer. See the sections on Positional</pre><pre style='margin-left:.5in'>Accuracy (Horizontal and Vertical) for additional</pre><pre style='margin-left:.5in'>information.</pre><pre style='margin-left:.5in'>Note that the discussions presented in the accuracy</pre><pre style='margin-left:.5in'>reports refer to contour intervals in multiple units</pre><pre style='margin-left:.5in'>(meters and feet). This was done purposefully to</pre><pre style='margin-left:.5in'>reflect the actual contour intervals used by USGS over</pre><pre style='margin-left:.5in'>the years and which vary on a quadrangle by quadrangle</pre><pre style='margin-left:.5in'>basis.</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><i>Completeness_Report:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>This data set generally corresponds to the source data</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>used in the layer development. See the sections on</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>Positional Accuracy (Horizontal and Vertical) for</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>additional information.</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>The vertical values and their associated positions were</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>generated using the interpolation function &quot;TOPOGRID&quot;</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>within the ESRI GRID module. TOPOGRID uses input</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>elevation data such as contours and elevation point</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>data along with supplemental information such as stream</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>networks, lakes (of known elevation), and bounding</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>areas to generate a hydrologically correct DEM. Each</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>state DEM was generated using TOPOGRID but the specific</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>parameters were unique to the data sets available and</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>issues related to each state. The specifics to each</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>state DEM are described under positional accuracy</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>section of the metadata and in process steps.</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>There are known issues relating to the interpolation</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>algorithm TOPOGRID.</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>TOPOGRID Plateau Problem. </pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>The TOPOGRID function</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>generates disproportionately large areas with the same</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>value of the input contour lines, e.g., if we have 5</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>and 10 foot contour lines, there would be substantially</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>more areas with values between 4 to 6 and 9 to 11, than</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>6 to 9 feet.. At the upper tips of narrow valleys, the</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>cell values tend to be the same as the bounding</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>contours; so the valleys become plateaus.</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>The TOPOGRID function within the ESRI GRID module tends</pre><pre style='margin-left:.5in'> <span style='mso-spacerun:yes'>    </span>to calculate a trend from neighboring contour lines.</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>As a result, TOPOGRID frequently creates erroneous</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>depressions on the plains adjacent to steep slopes,</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>often substantially below the contours between which</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>those depressions lie. It also creates plateaus along</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>contours, which can be problematic because they</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>overstate the amount of land barely above the wetlands</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>and right at the first contour, while understating the</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>amount of land halfway between the wetlands and the</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>first contour. To address these problems, we processed</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>the areas above and below the first contour separately.</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>However, this caused another problem. In narrow valleys</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>in the area below the first contour, the output DEM</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>values were similar or identical to those of the</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>bounding contour lines due to the lack of elevation</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>information that TOPOGRID needs to calculate trend. The</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>most problematic regions occurred where there was a</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>stream valley below the first contour (e.g. between two</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>parallel 5 foot contours), no open water or tidal</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>wetlands along most of the length of the valley, but</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>open water or tidal wetlands at one end of the valley</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>(e.g. a typical nontidal stream flowing into tidal</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>waters). In some cases, the trend from the wetlands or</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>open water at the mouth, toward the bounding first</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>contour, would provide values even higher than that</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>first contour farther up the valley. And in general,</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>TOPOGRID would be more likely to assume a flat area</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>between the contours, than to characterize it as a</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>valley--except for when stream data was used.</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span></pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span></pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>Other Issues: The decision to process 3 elevation areas</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>separately within TOPOGRID (as described in the process</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>step #4 - &quot;Interpolation of Digital Elevation Model&quot;)</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>and then combine them into a single DEM removes the</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>algorithm from its theoretical underpinning, because it</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>separates each elevation zone from the context of the</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>overall environment that TOPOGRID uses to generate a</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>hydrologically-correct DEM. Because the objective of</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>this DEM is to estimate elevations of lands close to</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>sea level, rather than characterize drainage correctly,</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>the ad hoc response to the TOPOGRID plateau problem is</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>not as unreasonable as would have been the case were</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>this data to be used for analyzing hydrology.</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>Nevertheless,<span style='mso-spacerun:yes'>  </span>modification of the tolerance values and</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>other parameters within TOPOGRID, and inclusion of</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>additional vertical data in areas of known errors</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>(determined through the use of diagnostic outputs</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>within the TOPOGRID function), probably could have</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>substantially diminished the plateau problem in the</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>vicinity of the first topographic contour. Because the</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>plateau problem around the edge of tidal wetlands was</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>often caused largely by the relative complexity of the</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>wetland supplemental contour compared with other</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>contours,<span style='mso-spacerun:yes'>  </span>the case for dividing the data as we did is</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>probably greater along the wetland boundary than along</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>the first contour.</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span></pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>Also see the sections on Positional Accuracy<span style='mso-spacerun:yes'>  </span>(Horizontal and Vertical) and process steps.</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><i>Positional_Accuracy:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Positional_Accuracy:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Positional_Accuracy:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Horizontal_Positional_Accuracy:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Horizontal_Positional_Accuracy_Report:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>The source data generally were 1:24,000 scale or</pre><pre style='margin-left:.5in'>better. Therefore our use of 30 meter cells</pre><pre style='margin-left:.5in'>deteriorated the horizontal accuracy.<span style='mso-spacerun:yes'>  </span>Assuming that</pre><pre style='margin-left:.5in'>90% of well defined points are within 30 meters of the</pre><pre style='margin-left:.5in'>indicated location would imply a scale of 1:60,000</pre><pre style='margin-left:.5in'>under National Map Accuracy Standards. (That assumption</pre><pre style='margin-left:.5in'>may be conservative because 100% of the points in a 30</pre><pre style='margin-left:.5in'>meter cell are less than 21.2 meters of the center of</pre><pre style='margin-left:.5in'>the cell.<span style='mso-spacerun:yes'>  </span>If the input map has 1:24,000 scale (well</pre><pre style='margin-left:.5in'>defined points within 12.2 meters)<span style='mso-spacerun:yes'>  </span>and errors are</pre><pre style='margin-left:.5in'>random, then more than 90% of the points will be within</pre><pre style='margin-left:.5in'>24.5 meters of the indicated location, which would</pre><pre style='margin-left:.5in'>imply a scale of 1:50,000.)<span style='mso-spacerun:yes'>  </span>However, our interpolation</pre><pre style='margin-left:.5in'>program may further deteriorate the horizontal</pre><pre style='margin-left:.5in'>accuracy.<span style='mso-spacerun:yes'>  </span>Under some circumstances, the horizontal error appears to be as great as the width of a cell.<span style='mso-spacerun:yes'>  </span>Given that the diagonal in this case would be 42.4 m, if errors are random, then the scale might be as poor as 1:86,000 in areas where those 1-cell errors are common.</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><i>Quantitative_Horizontal_Positional_Accuracy_Assessment:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Horizontal_Positional_Accuracy_Value:</i> 40-42.4 meters</p> <p class=MsoNormal style='margin-left:.5in'><i>Horizontal_Positional_Accuracy_Explanation:</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><i>Vertical_Positional_Accuracy:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Vertical_Positional_Accuracy_Report:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>The vertical accuracy of this data set generally corresponds to that of the source data (described below) used in the layer development, plus errors induced through the various processing steps.</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>The most important processing errors</pre><pre style='margin-left:.5in'>probably concern the procedures used to interpolate</pre><pre style='margin-left:.5in'>between contours, which do not necessarily correspond</pre><pre style='margin-left:.5in'>to the actual geometry of the land surfaces. Therefore,</pre><pre style='margin-left:.5in'>points that are near a contour have greater accuracy</pre><pre style='margin-left:.5in'>than 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 of<span style='mso-spacerun:yes'>  </span>DEMs generated by ICF Consulting, Russ Jones of Stratus Consulting Inc. compared DEMs with LIDAR data in two areas: 1) an area south of Rock Hall along the eastern shore of <st1:State w:st="on">Maryland</st1:State>, and 2) portions of <st1:State w:st="on"><st1:place w:st="on">North Carolina</st1:place></st1:State>. Table 1 within DEM_LidarComparisonTable.doc summarizes the comparison. 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'>approximately one-half of the input contour interval in cases</pre><pre style='margin-left:.5in'>where the contour interval was 1 meter, 5 feet, or 2</pre><pre style='margin-left:.5in'>meters.</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>In areas where the USGS contour interval was 20 feet</pre><pre style='margin-left:.5in'>and we used MD DNR data for supplemental contours, the</pre><pre style='margin-left:.5in'>mean discrepancy (LIDAR-DEM) was -2.4 feet with a RMS</pre><pre style='margin-left:.5in'>discrepancy of 6 feet for DEM observations less than 10</pre><pre style='margin-left:.5in'>feet. The error was much less (mean -1.1 feet, RMS 3.9</pre><pre style='margin-left:.5in'>feet) for DEM values between 10 and 20 feet NGVD29.</pre><pre style='margin-left:.5in'>Most of the errors appear to be centered in Caroline</pre><pre style='margin-left:.5in'>County, where the Maryland DNR data incorrectly showed</pre><pre style='margin-left:.5in'>a large area below 5 feet NGVD29. </pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>Jones also provided histograms showing the relationship between input contour</pre><pre style='margin-left:.5in'>intervals and the DEM values, for 11 USGS 7.5'</pre><pre style='margin-left:.5in'>topographical quadrangles in the study area from New</pre><pre style='margin-left:.5in'><st1:City w:st="on">York</st1:City> to <st1:State w:st="on"><st1:place w:st="on">North Carolina</st1:place></st1:State>, including Marcus Hook. The</pre><pre style='margin-left:.5in'>technical paper by Titus and Wang (2008, listed in the</pre><pre style='margin-left:.5in'>citation section above) analyzes the results of that</pre><pre style='margin-left:.5in'>comparison. Note that this comparison was conducted on the initial DEM generated with TOPOGRID. As a result of this analysis, the minimum and maximum elevation limits were constrained to ensure that the resulting elevations were in accordance with the input data. (See &quot;First-contour truncating&quot; in the process step on interpolation of Digital Elevation Model). That paper compares the area of land below</pre><pre style='margin-left:.5in'>the first, second, and third contour according to the</pre><pre style='margin-left:.5in'>DEM, with the area of the input polygons.<span style='mso-spacerun:yes'>  </span>That error</pre><pre style='margin-left:.5in'>can be considered both in terms of the difference in</pre><pre style='margin-left:.5in'>area estimates, and as a vertical error.<span style='mso-spacerun:yes'>  </span>As a measure</pre><pre style='margin-left:.5in'>of the vertical error, Titus and Wang consider the</pre><pre style='margin-left:.5in'>effective elevation of the DLG contour that the DEM</pre><pre style='margin-left:.5in'>estimates, that is, at what elevation does the DEM find</pre><pre style='margin-left:.5in'>the same amount of land that the DLG polygons show to</pre><pre style='margin-left:.5in'>be below the first contour.</pre><pre style='margin-left:.5in'>The technical paper also calculates a plateau</pre><pre style='margin-left:.5in'>exaggeration factor:<span style='mso-spacerun:yes'>  </span>The ratio of the area (according</pre><pre style='margin-left:.5in'>to the DEM) within 0.1 feet above or below a contour,</pre><pre style='margin-left:.5in'>to the area that one would expect if elevations were</pre><pre style='margin-left:.5in'>uniformly distributed between the contour above and (if</pre><pre style='margin-left:.5in'>it exists) the contour below.<span style='mso-spacerun:yes'>  </span>Suppose for example,</pre><pre style='margin-left:.5in'>spring high water is 2 ft NGVD, the contour</pre><pre style='margin-left:.5in'>interval is 5 feet, there are 3 ha between spring</pre><pre style='margin-left:.5in'>high water and the 5 ft contour, and 5 ha between the 5-</pre><pre style='margin-left:.5in'>and 10-foot contours, and the DEM finds 2ha between 4.9</pre><pre style='margin-left:.5in'>and 5.1 ft.<span style='mso-spacerun:yes'>  </span>The plateau exaggeration factor would be</pre><pre style='margin-left:.5in'>10, because a uniform elevation distribution would</pre><pre style='margin-left:.5in'>imply 1 ha per foot of elevation change; but around the</pre><pre style='margin-left:.5in'>plateau we have 2 ha within a 0.2 ft elevation</pre><pre style='margin-left:.5in'>increment.</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>This metadata discusses only the one quad in <st1:State w:st="on"><st1:place w:st="on">New York</st1:place></st1:State>,</pre><pre style='margin-left:.5in'>plus two quads in <st1:State w:st="on"><st1:place w:st="on">Maryland</st1:place></st1:State> that were particularly</pre><pre style='margin-left:.5in'>problematic.</pre><pre style='margin-left:.5in'>For the <st1:place w:st="on">Central Park</st1:place><span style='mso-spacerun:yes'>  </span>quad, the DEM</pre><pre style='margin-left:.5in'>underestimated the low land (below 10ft) implied by the</pre><pre style='margin-left:.5in'>DLG by 7%.<span style='mso-spacerun:yes'>  </span>Examining an overlay of the DEM and the</pre><pre style='margin-left:.5in'>DLG's, the discrepancy for land below the 10-foot</pre><pre style='margin-left:.5in'>contour appears to be largely explained by places where</pre><pre style='margin-left:.5in'>the cell size was<span style='mso-spacerun:yes'>  </span>larger than the distance between</pre><pre style='margin-left:.5in'>contours. The plateau exaggeration factors were 0.1,</pre><pre style='margin-left:.5in'>5.3, and 4.0 for the tidal wetland, 10-ft, and 20-ft</pre><pre style='margin-left:.5in'>contours, respectively.<span style='mso-spacerun:yes'>  </span>The<span style='mso-spacerun:yes'>  </span>plateau at the 10-ft</pre><pre style='margin-left:.5in'>contour had<span style='mso-spacerun:yes'>  </span>an area three times the size of the</pre><pre style='margin-left:.5in'>discrepancy between the DEM and polygon estimates of</pre><pre style='margin-left:.5in'>the amount of land below the 10-ft contour.<span style='mso-spacerun:yes'>  </span>As a</pre><pre style='margin-left:.5in'>result, in effect, the DEM estimates the DLG's 10-ft</pre><pre style='margin-left:.5in'>contour to be between 10 and 10.1 feet.<span style='mso-spacerun:yes'>  </span>The</pre><pre style='margin-left:.5in'>discrepancy for lands between 10-20 and 20-30 feet are</pre><pre style='margin-left:.5in'>less than 2%, which further supports the conclusion</pre><pre style='margin-left:.5in'>that part of the problem for the lowest land may be</pre><pre style='margin-left:.5in'>explained by areas where the dry land below 10 ft is</pre><pre style='margin-left:.5in'>too narrow to take up an entire cell (see discussion of</pre><pre style='margin-left:.5in'><st1:place w:st="on"><st1:City w:st="on">South River</st1:City>, <st1:State w:st="on">Maryland</st1:State></st1:place>, below).</pre><pre style='margin-left:.5in'>The discrepancies were more serious, however, for</pre><pre style='margin-left:.5in'>two quads in <st1:State w:st="on">Maryland</st1:State>:<span style='mso-spacerun:yes'>  </span>Broomes and <st1:place w:st="on">South River</st1:place>.<span style='mso-spacerun:yes'>  </span>For</pre><pre style='margin-left:.5in'>South River the DEM under estimates the amount of land</pre><pre style='margin-left:.5in'>below 5 ft by 50%.<span style='mso-spacerun:yes'>  </span>However, it is within 5% and 1% for</pre><pre style='margin-left:.5in'>the areas between 5-10 and 10-15ft, respectively.<span style='mso-spacerun:yes'>  </span>This</pre><pre style='margin-left:.5in'>error appears to have resulted because the land is</pre><pre style='margin-left:.5in'>sufficiently steep that particular cells will have more</pre><pre style='margin-left:.5in'>than one contour crossing them.<span style='mso-spacerun:yes'>  </span>The DEM assigns an</pre><pre style='margin-left:.5in'>average elevation to the cell.<span style='mso-spacerun:yes'>  </span>Assuming that the</pre><pre style='margin-left:.5in'>contours cross the centers of cells randomly, one would</pre><pre style='margin-left:.5in'>normally expect that the amount of higher and lower</pre><pre style='margin-left:.5in'>ground being &quot;averaged in&quot; would approximately offset</pre><pre style='margin-left:.5in'>each other, so that the DEM should find the same amount</pre><pre style='margin-left:.5in'>of land within a given elevation range as the input</pre><pre style='margin-left:.5in'>DLG's.<span style='mso-spacerun:yes'>  </span>Indeed, this appears to be the case for land at</pre><pre style='margin-left:.5in'>10-15 ft.<span style='mso-spacerun:yes'>  </span>For land below 5ft, however, there is higher</pre><pre style='margin-left:.5in'>ground but no lower ground to be &quot;averaged in.&quot;</pre><pre style='margin-left:.5in'>Therefore, an upward bias is created for the lowest</pre><pre style='margin-left:.5in'>areas.<span style='mso-spacerun:yes'>  </span>Such an upward bias in the lowest contour range</pre><pre style='margin-left:.5in'>could have been avoided with an algorithm that</pre><pre style='margin-left:.5in'>calculated elevations for points rather than cells or</pre><pre style='margin-left:.5in'>using a much smaller cell size.<span style='mso-spacerun:yes'>  </span>Doing so, however,</pre><pre style='margin-left:.5in'>would have increased the costs of this study several</pre><pre style='margin-left:.5in'>fold. The net impact was that the DEM, in effect,</pre><pre style='margin-left:.5in'>estimated the 5-ft contour to be approximately 7.3 ft</pre><pre style='margin-left:.5in'>above the vertical datum for <st1:place w:st="on">South River</st1:place>.<span style='mso-spacerun:yes'>  </span>The Broomes</pre><pre style='margin-left:.5in'>quad had a similar upward bias, effectively treating</pre><pre style='margin-left:.5in'>the 5-ft contour as a 5.8-ft contour.<span style='mso-spacerun:yes'>  </span></pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>The experience</pre><pre style='margin-left:.5in'>with those two quads in <st1:State w:st="on"><st1:place w:st="on">Maryland</st1:place></st1:State> should serve as a</pre><pre style='margin-left:.5in'>caution that in <st1:State w:st="on"><st1:place w:st="on">New York</st1:place></st1:State>, our results may be much</pre><pre style='margin-left:.5in'>less accurate in areas with slopes steep enough to have</pre><pre style='margin-left:.5in'>two contours within 30 meters (e.g. slopes greater than</pre><pre style='margin-left:.5in'>6% with 5-ft contours, or 12% with 10ft contours),</pre><pre style='margin-left:.5in'>especially in the area above the lowest contour.<span style='mso-spacerun:yes'>  </span>(Our</pre><pre style='margin-left:.5in'>first-contour truncating mitigates this upward bias</pre><pre style='margin-left:.5in'>below the first contour; for reasons explained in the</pre><pre style='margin-left:.5in'>metadata for the <st1:State w:st="on"><st1:place w:st="on">Maryland</st1:place></st1:State> study (dem_MD_shw_cm).<span style='mso-spacerun:yes'>   </span>In</pre><pre style='margin-left:.5in'><st1:State w:st="on"><st1:place w:st="on">New York</st1:place></st1:State>, this caution may be applicable along the</pre><pre style='margin-left:.5in'><st1:place w:st="on">Hudson River</st1:place>.</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</pre><pre style='margin-left:.5in'>DEM_Comparison_with_DLG_11_quads.xls., which is</pre><pre style='margin-left:.5in'>included in the zip file distributed with this dataset.</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><i>Quantitative_Vertical_Positional_Accuracy_Assessment:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Vertical_Positional_Accuracy_Explanation:</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'><i>Source_Information:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Source_Citation:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Citation_Information:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Originator:</i> US Geological Survey</p> <p class=MsoNormal style='margin-left:.5in'><i>Publication_Date:</i> Multiple</p> <p class=MsoNormal style='margin-left:.5in'><i>Title:</i></p> <p class=MsoNormal style='margin-left:.5in'>Large Scale USGS Digital Line Graph (DLG)</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://edc.usgs.gov/geodata/dlg_large/states/PA.html%3e" target=viewer><span lang=DE style='mso-ansi-language:DE'>&lt;http://edc.usgs.gov/geodata/dlg_large/states/PA.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'><i>Source_Scale_Denominator:</i> 24,000</p> <p class=MsoNormal style='margin-left:.5in'><i>Type_of_Source_Media:</i> Digital data</p> <p class=MsoNormal style='margin-left:.5in'><i>Source_Time_Period_of_Content:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Source_Currentness_Reference:</i></p> <p class=MsoNormal style='margin-left:.5in'>Multiple</p> <p class=MsoNormal style='margin-left:.5in'><i>Source_Contribution:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>Elevation Contours used in Spatial data and attributes.</pre><pre style='margin-left:.5in'>Some contours digitized from Digital Raster Graphics</pre><pre style='margin-left:.5in'>(DRGs). Source contours are 5, 10 , and 20 feet depending on</pre><pre style='margin-left:.5in'>the 7.5' topographic quadrangle used. The zip file with</pre><pre style='margin-left:.5in'>which this metadata is distributed will include a</pre><pre style='margin-left:.5in'>graphic<span style='mso-spacerun:yes'>  </span>defining the contour intervals of the input</pre><pre style='margin-left:.5in'>data, NY_Elevation_Data_Quality.jpg</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><i>Source_Information:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Source_Citation:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Citation_Information:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Originator:</i> Hunan Institute of Geograophy</p> <p class=MsoNormal style='margin-left:.5in'><i>Publication_Date:</i> Multiple</p> <p class=MsoNormal style='margin-left:.5in'><i>Title:</i></p> <p class=MsoNormal style='margin-left:.5in'>Coastal Digital Line Graphs</p> <p class=MsoNormal style='margin-left:.5in'><i>Online_Linkage:</i> <a href="%3chttp://edc.usgs.gov/geodata/dlg_large/states/PA.html%3e" target=viewer>&lt;http://edc.usgs.gov/geodata/dlg_large/states/PA.html&gt;</a> </p> <p class=MsoNormal style='margin-left:.5in'><i>Online_Linkage:</i> <a href="" target=viewer></a></p> <p class=MsoNormal style='margin-left:.5in'><i>Source_Scale_Denominator:</i> 24,000</p> <p class=MsoNormal style='margin-left:.5in'><i>Type_of_Source_Media:</i> Digital data</p> <p class=MsoNormal style='margin-left:.5in'><i>Source_Time_Period_of_Content:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Source_Currentness_Reference:</i></p> <p class=MsoNormal style='margin-left:.5in'>Multiple</p> <p class=MsoNormal style='margin-left:.5in'><i>Source_Contribution:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>Elevation Contours used in Spatial data and attributes</pre><pre style='margin-left:.5in'>for USGS quads where USGS DLG was unavailable.<span style='mso-spacerun:yes'>  </span>See</pre><pre style='margin-left:.5in'>&quot;Institute_of_Geography_DLG.doc&quot; for a list of quads</pre><pre style='margin-left:.5in'>where we used these DLG's. Source contours are 5, 10 feet, and 20 feet depending</pre><pre style='margin-left:.5in'>on the 7.5' topographic quadrangle used. The zip file</pre><pre style='margin-left:.5in'>with which this metadata is distributed will include a</pre><pre style='margin-left:.5in'>graphic defining contour intervals of the input data:</pre><pre style='margin-left:.5in'>NY_Elevation_Data_Quality.jpg</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><i>Source_Information:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Source_Citation:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Citation_Information:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Originator:</i> National Oceanic Service</p> <p class=MsoNormal style='margin-left:.5in'><i>Publication_Date:</i> Unknown</p> <p class=MsoNormal style='margin-left:.5in'><i>Publication_Time:</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'><i>Online_Linkage:</i> <a href="%3chttp://co-ops.nos.noaa.gov/bench.html%3e" target=viewer>&lt;http://co-ops.nos.noaa.gov/bench.html&gt;</a> </p> <p class=MsoNormal style='margin-left:.5in'><i>Source_Scale_Denominator:</i> 24,000</p> <p class=MsoNormal style='margin-left:.5in'><i>Type_of_Source_Media:</i> online</p> <p class=MsoNormal style='margin-left:.5in'><i>Source_Time_Period_of_Content:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Time_Period_Information:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Range_of_Dates/Times:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Beginning_Date:</i> 1981</p> <p class=MsoNormal style='margin-left:.5in'><i>Ending_Date:</i> 2000</p> <p class=MsoNormal style='margin-left:.5in'><i>Source_Currentness_Reference:</i></p> <p class=MsoNormal style='margin-left:.5in'>Relative to 1960-1978 Tidal Epoch</p> <p class=MsoNormal style='margin-left:.5in'><i>Source_Contribution:</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'>mean lower low water (MLLW), the elevation of MLLW</pre><pre style='margin-left:.5in'>relative to several benchmarks nearby, and the</pre><pre style='margin-left:.5in'>elevations of these benchmarks above NAVD88 for 22 tide</pre><pre style='margin-left:.5in'>gages in or around <st1:State w:st="on"><st1:place w:st="on">New York</st1:place></st1:State></pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><i>Source_Information:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Source_Citation:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Citation_Information:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Originator:</i> National Oceanic Service</p> <p class=MsoNormal style='margin-left:.5in'><i>Publication_Date:</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'><i>Geospatial_Data_Presentation_Form:</i> document</p> <p class=MsoNormal style='margin-left:.5in'><i>Source_Scale_Denominator:</i> NA</p> <p class=MsoNormal style='margin-left:.5in'><i>Type_of_Source_Media:</i> paper report, whose tables contained latitude, longitude, and tide range.</p> <p class=MsoNormal style='margin-left:.5in'><i>Source_Time_Period_of_Content:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Time_Period_Information:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Single_Date/Time:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Calendar_Date:</i> 2000</p> <p class=MsoNormal style='margin-left:.5in'><i>Source_Currentness_Reference:</i></p> <p class=MsoNormal style='margin-left:.5in'>publication date</p> <p class=MsoNormal style='margin-left:.5in'><i>Source_Contribution:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>Horizontal location, and spring high tide ranges for</pre><pre style='margin-left:.5in'>198 tide gages in or around <st1:State w:st="on"><st1:place w:st="on">New York</st1:place></st1:State></pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><i>Source_Information:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Source_Citation:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Citation_Information:</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'><i>Publication_Date:</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">New York</st1:place></st1:State></p> <p class=MsoNormal style='margin-left:.5in'><i>Source_Scale_Denominator:</i> 24,000</p> <p class=MsoNormal style='margin-left:.5in'><i>Type_of_Source_Media:</i> online</p> <p class=MsoNormal style='margin-left:.5in'><i>Source_Time_Period_of_Content:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Time_Period_Information:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Single_Date/Time:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Calendar_Date:</i> 2006</p> <p class=MsoNormal style='margin-left:.5in'><i>Source_Currentness_Reference:</i></p> <p class=MsoNormal style='margin-left:.5in'>publication date</p> <p class=MsoNormal style='margin-left:.5in'><i>Source_Contribution:</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'>wetlands. See Readme.doc (distributed in the zip file with this</pre><pre style='margin-left:.5in'>data set), for directions on how to download the</pre><pre style='margin-left:.5in'>Coastal Wetlands Data .<span style='mso-spacerun:yes'>  </span>See also the technical report for this project J.G. Titus 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 (eds.)]. 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.</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><i>Source_Information:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Source_Citation:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Citation_Information:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Originator:</i> Proudman Oceanographic Laboratory (POL)</p> <p class=MsoNormal style='margin-left:.5in'><i>Publication_Date:</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)- Sea Level Rise Trend Data</p> <p class=MsoNormal style='margin-left:.5in'><i>Other_Citation_Details:</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).</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'><i>Source_Scale_Denominator:</i> 24,000</p> <p class=MsoNormal style='margin-left:.5in'><i>Type_of_Source_Media:</i> online</p> <p class=MsoNormal style='margin-left:.5in'><i>Source_Time_Period_of_Content:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Time_Period_Information:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Single_Date/Time:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Calendar_Date:</i> unknown</p> <p class=MsoNormal style='margin-left:.5in'><i>Source_Currentness_Reference:</i></p> <p class=MsoNormal style='margin-left:.5in'>publication date</p> <p class=MsoNormal style='margin-left:.5in'><i>Source_Contribution:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>Spatial location and estimates of the rate of sea level rise.</pre><pre style='margin-left:.5in'>Elevation contours were used to generate a surface of sea level rise rates.</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><i>Source_Information:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Source_Citation:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Citation_Information:</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, Office of Science and Technology</p> <p class=MsoNormal style='margin-left:.5in'><i>Publication_Date:</i> 1994</p> <p class=MsoNormal style='margin-left:.5in'><i>Title:</i></p> <p class=MsoNormal style='margin-left:.5in'><st1:country-region w:st="on">U.S.</st1:country-region> EPA Reach File 1 (RF1) for the Conterminous <st1:country-region w:st="on"><st1:place w:st="on">United States</st1:place></st1:country-region> in BASINS</p> <p class=MsoNormal style='margin-left:.5in'><i>Edition:</i> Version 2.0</p> <p class=MsoNormal style='margin-left:.5in'><i>Online_Linkage:</i> <a href="For%20BASINS%20model%20and%20data%20%3chttp:/www.epa.gov/waterscience/basins/%3e" target=viewer>For BASINS model and data &lt;http://www.epa.gov/waterscience/basins/&gt;</a> </p> <p class=MsoNormal style='margin-left:.5in'><i>Source_Scale_Denominator:</i> 250,000 to 500,000</p> <p class=MsoNormal style='margin-left:.5in'><i>Type_of_Source_Media:</i> CD-ROM</p> <p class=MsoNormal style='margin-left:.5in'><i>Source_Time_Period_of_Content:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Time_Period_Information:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Single_Date/Time:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Calendar_Date:</i> 1994</p> <p class=MsoNormal style='margin-left:.5in'><i>Source_Currentness_Reference:</i></p> <p class=MsoNormal style='margin-left:.5in'>publication date</p> <p class=MsoNormal style='margin-left:.5in'><i>Source_Contribution:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>Spatial data and attributes</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><i>Process_Step:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Process_Description:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>Process of Input Elevation Data</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>1) Input elevation contour lines were either 1:24,000</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>USGS DLGs or 1:24,000 DLG's created by the Institute of</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>Geography (using USGS DRG's)<span style='mso-spacerun:yes'>  </span>They were appended and</pre><pre style='margin-left:.5in'><span style='mso-spacerun:yes'>     </span>then projected into Albers projection..</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><i>Process_Contact:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Information:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Person_Primary:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Person:</i> Jue Wang</p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Organization:</i> GIS Practice, ICF Consulting, Inc.</p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Position:</i> Senior GIS Analyst</p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Address:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Address_Type:</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'><i>State_or_Province:</i> VA</p> <p class=MsoNormal style='margin-left:.5in'><i>Postal_Code:</i> 22031</p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Voice_Telephone:</i> 703-218-2766</p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Facsimile_Telephone:</i> 703-934-3974</p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Electronic_Mail_Address:</i> jwang@icfconsulting.com</p> <p class=MsoNormal style='margin-left:.5in'><i>Hours_of_Service:</i> 9:30 - 5:30 EST</p> <p class=MsoNormal style='margin-left:.5in'><i>Process_Step:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Process_Description:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>Process of Tidal Record: Calculating the Elevation of</pre><pre style='margin-left:.5in'>Spring High Water Supplemental Contour</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></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'>latitudes and longitudes, the elevations of mean tide</pre><pre style='margin-left:.5in'>level (MTL) above mean lower low water (MLLW), the</pre><pre style='margin-left:.5in'>elevations of MLLW relative to several benchmarks, and</pre><pre style='margin-left:.5in'>the elevations above NAVD88 of these benchmarks of 22</pre><pre style='margin-left:.5in'>tide gages in or near <st1:State w:st="on"><st1:place w:st="on">New York</st1:place></st1:State> were downloaded from the</pre><pre style='margin-left:.5in'>NOS website. The elevations of mean tide level above</pre><pre style='margin-left:.5in'>NAVD88 were calculated and then converted to above</pre><pre style='margin-left:.5in'>NGVD29 using USGS VERTCON program. A point coverage was</pre><pre style='margin-left:.5in'>then created with such data and projected into Albers</pre><pre style='margin-left:.5in'>projection. Using the point coverage as a reference,</pre><pre style='margin-left:.5in'>artificial contour lines were created with</pre><pre style='margin-left:.5in'>consideration of shorelines via heads-up digitizing and</pre><pre style='margin-left:.5in'>then used to interpolate the mean tide level surface</pre><pre style='margin-left:.5in'>using a Triangular Irregular Network (TIN).<span style='mso-spacerun:yes'>  </span>As the</pre><pre style='margin-left:.5in'>tidal epoch used for the MTL data was 1960-1978, a</pre><pre style='margin-left:.5in'>separate sea level rise rate surface was created by</pre><pre style='margin-left:.5in'>interpolating actual sea level rise data (trend) from</pre><pre style='margin-left:.5in'>the Proudman Oceanographic Laboratory website and was</pre><pre style='margin-left:.5in'>used to adjust the mean tide level to years</pre><pre style='margin-left:.5in'>corresponding to other data sets, such as NWI data, so</pre><pre style='margin-left:.5in'>that the wetland boundary would represent spring high</pre><pre style='margin-left:.5in'>tide for the year the map imagery was taken.</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></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'>of &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'>tide ranges of 198 tide gauges in or near <st1:State w:st="on"><st1:place w:st="on">New York</st1:place></st1:State> were</pre><pre style='margin-left:.5in'>obtained and used to create a point coverage. Using the</pre><pre style='margin-left:.5in'>point coverage as a reference, artificial contour lines</pre><pre style='margin-left:.5in'>were created with consideration of shorelines and then</pre><pre style='margin-left:.5in'>used to interpolate the spring high tide range surface</pre><pre style='margin-left:.5in'>with the TIN method.</pre><pre style='margin-left: .5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>3) Creation of a Spring High Water Level Surface. A</pre><pre style='margin-left:.5in'>spring high water level surface was created by adding</pre><pre style='margin-left:.5in'>half of spring tide range onto mean tide level surface.</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><i>Process_Contact:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Information:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Person_Primary:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Person:</i> Jue Wang</p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Organization:</i> GIS Practice, ICF Consulting, Inc.</p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Position:</i> Senior GIS Analyst</p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Voice_Telephone:</i> 703-218-2766</p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Facsimile_Telephone:</i> 703-934-3974</p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Electronic_Mail_Address:</i> jwang@icfconsulting.com</p> <p class=MsoNormal style='margin-left:.5in'><i>Process_Step:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Process_Description:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>Processing Tidal Wetlands:</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></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) We identified the upper limit of tidal wetland by</pre><pre style='margin-left:.5in'>extracting the boundaries of tidal polygons (consisting</pre><pre style='margin-left:.5in'>of tidal wetland and tidal open water) and non-tidal</pre><pre style='margin-left:.5in'>polygons (consisting of dry land, non-tidal wetland,</pre><pre style='margin-left:.5in'>and non-tidal open water).</pre><pre style='margin-left: .5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>2) We used the upper and lower limits of tidal wetlands</pre><pre style='margin-left:.5in'>to generate supplemental contours. We assigned these</pre><pre style='margin-left:.5in'>contours elevations derived from spring high tide level</pre><pre style='margin-left:.5in'>and mean tide level surface grids respectively. The</pre><pre style='margin-left:.5in'>upper wetland boundary was used as a supplemental</pre><pre style='margin-left:.5in'>contour. The lower boundary was used for reporting the</pre><pre style='margin-left:.5in'>area of wetlands but not for elevations, because the</pre><pre style='margin-left:.5in'>project manager decided not to report wetland</pre><pre style='margin-left:.5in'>elevations.</pre><pre style='margin-left:.5in'>See also the metadata accompanying the Coastal Wetlands</pre><pre style='margin-left:.5in'>Data: <st1:State w:st="on"><st1:place w:st="on">New York</st1:place></st1:State>&quot;<span style='mso-spacerun:yes'>  </span>polygon<span style='mso-spacerun:yes'>  </span>dataset</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><i>Process_Contact:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Information:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Person_Primary:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Person:</i> Jue Wang</p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Organization:</i> ICF Consulting, Inc., GIS Practice</p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Position:</i> Senior GIS Analyst</p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Voice_Telephone:</i> 703-218-2766</p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Facsimile_Telephone:</i> 703-934-3974</p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Electronic_Mail_Address:</i> jwang@icfconsulting.com</p> <p class=MsoNormal style='margin-left:.5in'><i>Process_Step:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Process_Description:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>Interpolation of Digital Elevation Model</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>1) The study area was divided into four parts (tidal</pre><pre style='margin-left:.5in'>wetlands, lowland, midland, 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 between the tidal wetlands and the</pre><pre style='margin-left:.5in'>lowest USGS contour available, which is generally above</pre><pre style='margin-left:.5in'>the tidal wetlands. Depending on the contour interval</pre><pre style='margin-left:.5in'>of the input data, this lowest contour may have been 5</pre><pre style='margin-left:.5in'>feet, 10 feet, or 20 feet -- in all cases relative to</pre><pre style='margin-left:.5in'>NGVD29.</pre><pre style='margin-left:.5in'><st1:City w:st="on"><st1:place w:st="on">Midland</st1:place></st1:City> represents the area above the lowest contour we</pre><pre style='margin-left:.5in'>used and below the highest USGS contour lines (40 foot</pre><pre style='margin-left:.5in'>NGVD29) used.</pre><pre style='margin-left:.5in'><st1:City w:st="on"><st1:place w:st="on">Upland</st1:place></st1:City> represents land above the midland contour (i.e.,</pre><pre style='margin-left:.5in'>above the 40 foot NGVD29 contour).</pre><pre style='margin-left:.5in'>Boundary coverages were created for tidal wetlands,</pre><pre style='margin-left:.5in'>lowland, and midland using appropriate elevation</pre><pre style='margin-left:.5in'>contours or upper and lower limits of tidal wetland.</pre><pre style='margin-left:.5in'>However, we are not making the tidal wetland</pre><pre style='margin-left:.5in'>interpolations available in this dataset due to the</pre><pre style='margin-left:.5in'>lack of a theoretical justification for believing that</pre><pre style='margin-left:.5in'>interpolation to have any information content. (At</pre><pre style='margin-left:.5in'>best, the wetland elevation interpolations might be</pre><pre style='margin-left:.5in'>used for graphical representations of the impact of sea</pre><pre style='margin-left:.5in'>level rise.) We will retain a companion dataset with</pre><pre style='margin-left:.5in'>elevations stored as floating point double precision,</pre><pre style='margin-left:.5in'>which may be made available for the sole purpose of</pre><pre style='margin-left:.5in'>evaluating any graphical representations that use</pre><pre style='margin-left:.5in'>wetland elevations. We provide a<span style='mso-spacerun:yes'>  </span>a polygon wetland</pre><pre style='margin-left:.5in'>dataset so that the user can<span style='mso-spacerun:yes'>  </span>distinguish tidal</pre><pre style='margin-left:.5in'>wetlands from open water for cells with no data.</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>2) The DEMs were interpolated with a predetermined</pre><pre style='margin-left:.5in'>cell size of 30 meters for the lowland, midland, and</pre><pre style='margin-left:.5in'>upland areas using contour lines described in Process</pre><pre style='margin-left:.5in'>step 1 (the section &quot;Process of Input Elevation Data&quot;)</pre><pre style='margin-left:.5in'>and the supplemental contours explained in process step</pre><pre style='margin-left:.5in'>3. A common starting coordinate was set for all three</pre><pre style='margin-left:.5in'>DEM interpolation processes to ensure alignment of the</pre><pre style='margin-left:.5in'>separate layers after processing. The minimum and</pre><pre style='margin-left:.5in'>maximum limits were set for each process according to</pre><pre style='margin-left:.5in'>the input elevation data to ensure the resulting</pre><pre style='margin-left:.5in'>elevations were in accordance with the input data. See</pre><pre style='margin-left:.5in'>&quot;first contour truncating&quot;, paragraph 5, below. </pre><pre style='margin-left:.5in'>The iteration was set to 40, the</pre><pre style='margin-left:.5in'>horizontal standard error tolerance was set to 2 to</pre><pre style='margin-left:.5in'>minimize the depression caused by inappropriate tend</pre><pre style='margin-left:.5in'>calculation, and the drainage enforcement option was</pre><pre style='margin-left:.5in'>turned on to remove isolated depressions. In addition, we used stream data, which takes priority over the other elevation inputs, to add additional topographic detail.</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>The following represents the options used in TOPOGRID:</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>topogrid dem_mid_ft 30</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>contour topo_cntr elevation</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>xyzlimits 1712800 # 1960000 # 5.0001</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>boundary topo_bnd_mid</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>stream stream</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>iterations 40</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>tolerances # 2</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>enforce on</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>end</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>3) The interpolated DEMs were displayed against input</pre><pre style='margin-left:.5in'>elevation data and visually checked. These visual</pre><pre style='margin-left:.5in'>checks would show gross errors, but not necessarily</pre><pre style='margin-left:.5in'>errors in which the amount of low land is over- or</pre><pre style='margin-left:.5in'>underestimated by 10-40 percent (additionally, see Data</pre><pre style='margin-left:.5in'>Quality, Positional Accuracy section). If obvious</pre><pre style='margin-left:.5in'>errors such as artificial depressions occurred,</pre><pre style='margin-left:.5in'>supplemental elevation lines were added by heads-up</pre><pre style='margin-left:.5in'>digitizing to the input contour lines and the</pre><pre style='margin-left:.5in'>interpolation was repeated.</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>4) First-contour truncating. As a result of the comparison between the initial DEM and the source contours for 11 USGS quadrangles (see vertical accuracy report), we decided to reset the DEM values to coincide with source contours. Our general approach was</pre><pre style='margin-left:.5in'>that whenever TOPOGRID calculated a value greater than</pre><pre style='margin-left:.5in'>the first contour within the &quot;lowland&quot;, we reset the</pre><pre style='margin-left:.5in'>value to 0.001 less than the first contour. Whenever</pre><pre style='margin-left:.5in'>TOPOGRID calculated a midland value less than the first</pre><pre style='margin-left:.5in'>contour, we reset the value to 0.001 greater than the</pre><pre style='margin-left:.5in'>first contour. Given the rounding of this integer</pre><pre style='margin-left:.5in'>dataset, all such values are effectively rounded to the</pre><pre style='margin-left:.5in'>bounding contour value between midland and lowland</pre><pre style='margin-left:.5in'>(e.g. 5 feet). Although this approach leaves us with</pre><pre style='margin-left:.5in'>some plateaus, we have fewer plateaus than we had when</pre><pre style='margin-left:.5in'>we did not divide the data; and dividing the data left</pre><pre style='margin-left:.5in'>us with fewer cases of midland and lowland values being</pre><pre style='margin-left:.5in'>outside of their appropriate ranges</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>5) The DEMs of each separate part were eventually</pre><pre style='margin-left:.5in'>merged into the final DEM with the MERGE function</pre><pre style='margin-left:.5in'>within the ESRI GRID module.</pre><pre style='margin-left:.5in'><o:p>&nbsp;</o:p></pre><pre style='margin-left:.5in'>6) Elevations for <st1:place w:st="on"><st1:PlaceName w:st="on">Long Beach</st1:PlaceName> <st1:PlaceType w:st="on">Island</st1:PlaceType></st1:place> were found to be </pre><pre style='margin-left:.5in'>inaccurate due to the dearth of 10ft contours in the area. </pre><pre style='margin-left:.5in'>More detailed contours were heads-up digitized from benchmarks </pre><pre style='margin-left:.5in'>and 10ft contours found on the 1:24,000 USGS Lawrence, NY </pre><pre style='margin-left:.5in'>quadrangle. We then (as described above) used TOPOGRID to </pre><pre style='margin-left:.5in'>interpolate our contour lines to a grid and MERGE to update </pre><pre style='margin-left:.5in'>our existing DEM.</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><i>Process_Contact:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Information:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Person_Primary:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Person:</i> Thomas Hodgson</p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Organization:</i> Stratus Consulting Inc.</p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Position:</i> Senior Associate</p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Voice_Telephone:</i> 303-381-8000</p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Facsimile_Telephone:</i> 303-381-8200</p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Electronic_Mail_Address:</i> thodgson@stratusconsulting.com</p> <p class=MsoNormal style='margin-left:.5in'><i>Cloud_Cover:</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><i>Spatial_Data_Organization_Information:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Direct_Spatial_Reference_Method:</i> Raster</p> <p class=MsoNormal style='margin-left:.5in'><i>Raster_Object_Information:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Raster_Object_Type:</i> Grid Cell</p> <p class=MsoNormal style='margin-left:.5in'><i>Row_Count:</i> 6526</p> <p class=MsoNormal style='margin-left:.5in'><i>Column_Count:</i> 8739</p> <p class=MsoNormal style='margin-left:.5in'><i>Vertical_Count:</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><i>Spatial_Reference_Information:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Horizontal_Coordinate_System_Definition:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Planar:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Map_Projection:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Map_Projection_Name:</i> Albers Conical Equal Area</p> <p class=MsoNormal style='margin-left:.5in'><i>Albers_Conical_Equal_Area:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Standard_Parallel:</i> 29.500000</p> <p class=MsoNormal style='margin-left:.5in'><i>Standard_Parallel:</i> 45.500000</p> <p class=MsoNormal style='margin-left:.5in'><i>Longitude_of_Central_Meridian:</i> -96.000000</p> <p class=MsoNormal style='margin-left:.5in'><i>Latitude_of_Projection_Origin:</i> 23.000000</p> <p class=MsoNormal style='margin-left:.5in'><i>False_Easting:</i> 0.000000</p> <p class=MsoNormal style='margin-left:.5in'><i>False_Northing:</i> 0.000000</p> <p class=MsoNormal style='margin-left:.5in'><i>Planar_Coordinate_Information:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Planar_Coordinate_Encoding_Method:</i> row and column</p> <p class=MsoNormal style='margin-left:.5in'><i>Coordinate_Representation:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Abscissa_Resolution:</i> 30.000000</p> <p class=MsoNormal style='margin-left:.5in'><i>Ordinate_Resolution:</i> 30.000000</p> <p class=MsoNormal style='margin-left:.5in'><i>Planar_Distance_Units:</i> meters</p> <p class=MsoNormal style='margin-left:.5in'><i>Geodetic_Model:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Horizontal_Datum_Name:</i> North American Datum of 1983</p> <p class=MsoNormal style='margin-left:.5in'><i>Ellipsoid_Name:</i> Geodetic Reference System 80</p> <p class=MsoNormal style='margin-left:.5in'><i>Semi-major_Axis:</i> 6378137.000000</p> <p class=MsoNormal style='margin-left:.5in'><i>Denominator_of_Flattening_Ratio:</i> 298.257222</p> <p class=MsoNormal style='margin-left:.5in'><i>Vertical_Coordinate_System_Definition:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Altitude_System_Definition:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Altitude_Datum_Name:</i> SHW</p> <p class=MsoNormal style='margin-left:.5in'><i>Altitude_Resolution:</i> 1 cm</p> <p class=MsoNormal style='margin-left:.5in'><i>Altitude_Distance_Units:</i> cm</p> <p class=MsoNormal style='margin-left:.5in'><i>Altitude_Encoding_Method:</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><i>Entity_and_Attribute_Information:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Detailed_Description:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Entity_Type:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Entity_Type_Label:</i> dem_ny_shw_cm.vat</p> <p class=MsoNormal style='margin-left:.5in'><i>Attribute:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Attribute_Label:</i> Rowid</p> <p class=MsoNormal style='margin-left:.5in'><i>Attribute_Definition:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>Internal feature number.</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><i>Attribute_Definition_Source:</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><i>Attribute_Domain_Values:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Unrepresentable_Domain:</i></p> <p class=MsoNormal style='margin-left:.5in'>Sequential unique whole numbers that are automatically generated.</p> <p class=MsoNormal style='margin-left:.5in'><i>Attribute:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Attribute_Label:</i> VALUE</p> <p class=MsoNormal style='margin-left:.5in'><i>Attribute:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Attribute_Label:</i> Value</p> <p class=MsoNormal style='margin-left:.5in'><i>Attribute_Definition:</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><i>Attribute_Definition_Source:</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><i>Attribute_Value_Accuracy_Information:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Attribute_Value_Accuracy:</i> 1 cm</p> <p class=MsoNormal style='margin-left:.5in'><i>Attribute_Value_Accuracy_Explanation:</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'><i>Attribute_Label:</i> COUNT</p> <p class=MsoNormal style='margin-left:.5in'><i>Attribute_Definition:</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><i>Attribute_Definition_Source:</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><i>Overview_Description:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Entity_and_Attribute_Overview:</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'>spot elevations) and interpolated into a raster DEM and</pre><pre style='margin-left:.5in'>rounded to nearest cm.</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><i>Entity_and_Attribute_Detail_Citation:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>See process</pre><pre style='margin-left:.5in'>steps.</pre> <p class=MsoNormal><script> fix(original) </script><a href="#Top">Back to Top</a> <a name=33898336></a></p> <div class=MsoNormal align=center style='text-align:center'><span style='mso-bookmark:33898336'> <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:33898336'></span></span> <p class=MsoNormal><i>Distribution_Information:</i> </p> <p class=MsoNormal style='margin-left:.5in'><i>Distributor:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Information:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Organization_Primary:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Organization:</i> US Environmental Protection Agency, Climate Change Division</p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Address:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Address_Type:</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'><i>State_or_Province:</i> DC</p> <p class=MsoNormal style='margin-left:.5in'><i>Postal_Code:</i> 20460</p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Voice_Telephone:</i> 202-343-9990</p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Facsimile_Telephone:</i> 202-343-2338</p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Electronic_Mail_Address:</i> climatechange@epa.gov</p> <p class=MsoNormal style='margin-left:.5in'><i>Resource_Description:</i> The dataset is being distributed by the US Environmental Protection Agency.</p> <p class=MsoNormal style='margin-left:.5in'><i>Distribution_Liability:</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'>the EPA, no warranty expressed or implied is made</pre><pre style='margin-left:.5in'>regarding the accuracy or utility of the data. Neither</pre><pre style='margin-left:.5in'>EPA nor the data developers shall be held liable for</pre><pre style='margin-left:.5in'>any use of the data and information</pre><pre style='margin-left:.5in'>described and/or contained herein.</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><i>Standard_Order_Process:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Digital_Form:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Digital_Transfer_Information:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Transfer_Size:</i> 4.197</p> <p class=MsoNormal style='margin-left:.5in'><i>Custom_Order_Process:</i><o:p></o:p></p> <pre style='margin-left:.5in' id=original>Data available to CCSP collaborators from Alan Cohn at 202-343-9814.</pre> <p class=MsoNormal style='margin-left:.5in'><script> fix(original) </script><i>Technical_Prerequisites:</i></p> <p class=MsoNormal style='margin-left:.5in'>Requires software capable of displaying raster data.</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><i>Metadata_Reference_Information:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Metadata_Date:</i> 20080902</p> <p class=MsoNormal style='margin-left:.5in'><i>Metadata_Contact:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Information:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Person_Primary:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Person:</i> Russ Jones, Jim Titus, and Jue Wang</p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Organization:</i> Stratus Consulting Inc. (Jones)</p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Position:</i> Managing Analyst (Jones)</p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Address:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Address_Type:</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'><i>State_or_Province:</i> CO</p> <p class=MsoNormal style='margin-left:.5in'><i>Postal_Code:</i> 80306</p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Voice_Telephone:</i> 303-381-8000 (Jones)</p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Voice_Telephone:</i> 202-343-9307 (Titus)</p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Facsimile_Telephone:</i> 303-381-8200 (Jones)</p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Electronic_Mail_Address:</i> rjones@stratusconsulting.com</p> <p class=MsoNormal style='margin-left:.5in'><i>Contact_Electronic_Mail_Address:</i> Titus.Jim@epamail.epa.gov</p> <p class=MsoNormal style='margin-left:.5in'><i>Hours_of_Service:</i> 9:00 - 5:00 MST</p> <p class=MsoNormal style='margin-left:.5in'><i>Metadata_Standard_Name:</i> FGDC Content Standards for Digital Geospatial Metadata</p> <p class=MsoNormal style='margin-left:.5in'><i>Metadata_Standard_Version:</i> FGDC-STD-001-1998</p> <p class=MsoNormal style='margin-left:.5in'><i>Metadata_Time_Convention:</i> local time</p> <p class=MsoNormal style='margin-left:.5in'><i>Metadata_Extensions:</i></p> <p class=MsoNormal style='margin-left:.5in'><i>Online_Linkage:</i> <a href="http://www.esri.com/metadata/esriprof80.html" target=viewer>http://www.esri.com/metadata/esriprof80.html</a> </p> <p class=MsoNormal style='margin-left:.5in'><i>Profile_Name:</i> ESRI Metadata Profile</p> <p class=MsoNormal><a href="#Top">Back to Top</a> </p> </div> </body> </html>