<!DOCTYPE metadata SYSTEM "http://fgdc.gov/metadata/fgdc-std-001-1998.dtd">
<!--DOCTYPE metadata SYSTEM "fgdc-std-001-1998.dtd"--><metadata>	
	<idinfo>
		<citation>
			<citeinfo>
				<origin>Quantum Spatial, Inc.</origin>
				<pubdate>20170126</pubdate>
				<title>Mississippi 2016 QL2 LiDAR - South AOI; Hydro-Flattened DEM</title>
				<geoform>Raster digital data</geoform>
			</citeinfo>
		</citation>
		<descript>
			<abstract>Product: Product: These are Digital Elevation Model (DEM) data for Forrest, Greene, Lamar and Perry counties, Mississippi as part of the required deliverables for the Mississippi 2016 QL2 LiDAR project. Class 2 (ground) lidar points in conjunction with the hydro breaklines were used to create a 1 meter hydro-flattened raster DEM.
				Geographic Extent: Four whole and partial counties in south central Mississippi, covering approximately 1,507 square miles of the 3,825 total square mile project area.
				Dataset Description: The Mississippi 2016 Aerial LiDAR Mapping project called for the planning, acquisition, processing and derivative products of LIDAR data to be collected at an aggregate nominal pulse spacing (NPS) of 0.7 meters.  Project specifications are based on the U.S. Geological Survey National Geospatial Program Base LIDAR Specification, Version 1.2.  The data was developed based on a horizontal projection/datum of NAD83 (2011) State Plane Mississippi East Zone, US survey feet and vertical datum of NAVD1988 (Geoid 12B), US survey feet. LiDAR data was delivered in RAW flight line swath format, processed to create Classified LAS 1.4 Files formatted to 1,791 individual 5,000-foot x 5,000-foot tiles. Corresponding 2.5-foot intensity images in GeoTIFF format and 2.5-foot bare-earth DEM files in ERDAS .IMG format were created with the same tile schema. Tiles names follow the US National Grid naming schema. Hydro-flattened breaklines were produced in Esri file geodatabase format. Continuous contours with a 1-foot interval were produced in Esri file geodatabase format. 
				Ground Conditions: Lidar was collected in winter of 2016, while no snow was on the ground and rivers were at or below normal levels. In order to post process the lidar data to meet task order specifications and meet ASPRS vertical accuracy guidelines, Quantum Spatial, Inc. established a total of 38 ground control points that were used to calibrate the lidar to known ground locations established throughout the Mississippi project area. An additional 96 independent accuracy checkpoints, 43 in Bare Earth and Urban landcovers (43 NVA points), 35 in Forested, Shrubs, and Tall Weeds categories (35 VVA points), were used to assess the vertical accuracy of the data. These checkpoints were not used to calibrate or post process the data. One point was removed from the NVA calculations due to drastic change in the area.</abstract>
			<purpose>To acquire detailed surface elevation data for use in conservation planning, design, research, floodplain mapping, dam safety assessments and elevation modeling, etc. Classified LAS files are used to show the manually reviewed bare earth surface. This allows the user to create intensity images, breaklines and raster DEMs. The purpose of these lidar data was to produce high accuracy 3D hydro-flattened digital elevation models (DEMs) with a 2.5 foot cell size. These raw lidar point cloud data were used to create classified lidar LAS files, intensity images, 3D breaklines, hydro-flattened DEMs, and contours as necessary.</purpose>
			<supplinf>
				Raster File Type = IMG
				Bit Depth/Pixel Type = 32-bit float
				Raster Cell Size = 2.5 US Survey Feet
				Interpolation or Resampling Technique = Triangulated Irregular Network (TIN), Linear Interpolation, Proprietary
				Tile MS845675 contains data flown on both 1/19/2016 (flightline 130) and  1/27/2016 (flightline 137).  The hydro-flattened double line drain flows monotonically, based on the corresponding data used to collect the breakline from each date.  A step was introduced in the location between flightlines because of a 5 foot rise in the water elevation between these 2 lifts.
     </supplinf>
		</descript>
		<timeperd>
			<timeinfo>
				<rngdates>
					<begdate>20160119</begdate>
					<enddate>20160204</enddate>
				</rngdates>
			</timeinfo>
			<current>ground condition</current>
		</timeperd>
		<status>
			<progress>Complete</progress>
			<update>None planned</update>
		</status>
		<spdom>
			<bounding>
				<westbc>-89.6645579701677</westbc> 
				<eastbc>-88.6871709429993</eastbc> 
				<northbc>31.4380733391558</northbc>
				<southbc>30.9012662914909</southbc>
			</bounding>
		</spdom>
		<keywords>
			<theme>
				<themekt>None</themekt>
				<themekey>Model</themekey>
				<themekey>Raster</themekey>
				<themekey>DEM</themekey>
				<themekey>Remote Sensing</themekey>
				<themekey>Elevation Data</themekey>
				<themekey>Lidar</themekey>
			</theme>
			<place>
				<placekt>None</placekt>
				<placekey>Mississippi</placekey>
				<placekey>Forrest County</placekey>
				<placekey>Greene County</placekey>
				<placekey>Lamar County</placekey>
				<placekey>Perry County</placekey>
			</place>
		</keywords>
		<accconst>No restrictions apply to this data.</accconst>
		<useconst>None. However, users should be aware that temporal changes may have occurred since this dataset was collected and that some parts of these data may no longer represent actual surface conditions. Users should not use these data for critical applications without a full awareness of its limitations. Acknowledgement of the U.S. Geological Survey would be appreciated for products derived from these data.</useconst>
	</idinfo>
	<dataqual>
		<logic>Data covers the entire area specified for this project.</logic>
		<complete>Datasets contain complete coverage of tiles. No points have been removed or excluded. A visual qualitative assessment was performed to ensure data completeness. There are no void areas or missing data. The raw point cloud is of good quality and data passes Non-Vegetated Vertical Accuracy specifications.</complete>
		<posacc>
			<vertacc>
				<vertaccr>The project specifications require the accuracy (ACCz) of the derived DEM be calculated and reported in two ways: 1. The required NVA is: 19.6 cm at a 95% confidence level, derived according to NSSDA, i.e., based on RMSE of 10 cm in the "bare earth" and "urban" land cover classes. This is a required accuracy. The NVA was tested with 42 of 43 checkpoints located in bare earth and urban (non-vegetated) areas. One point was removed from the NVA calculations due to drastic change in the area. 2. Vegetated Vertical Accuracy (VVA): VVA shall be reported for "forested", "shrubs", and "tall weeds" land cover classes. The target VVA is: 29.4 cm at the 95th percentile, derived according to ASPRS Guidelines, Vertical Accuracy Reporting for Lidar Data, i.e., based on the 95th percentile error in all vegetated land cover classes combined. This is a target accuracy. The VVA was tested with 35 checkpoints located in forested, shrubs, and tall weeds (vegetated) areas. The checkpoints were distributed throughout the project area and were surveyed using GPS techniques. See survey report for additional survey methodologies. AccuracyZ has been tested to meet 19.6 cm or better Non-Vegetated Vertical Accuracy at 95% confidence level using RMSE(z) x 1.9600 as defined by the National Standards for Spatial Data Accuracy (NSSDA); assessed and reported using National Digital Elevation Program (NDEP)/ASRPS Guidelines.</vertaccr>
				<qvertpa>
					<vertaccv>0.091</vertaccv>
					<vertacce>Tested 0.091 meters (0.298 feet) NVA at a 95% confidence level using RMSE(z) x 1.9600 as defined by the National Standards for Spatial Data Accuracy (NSSDA). The NVA of the DEM was calculated using 42 of the 43 collected independent checkpoints located in the Bare Earth and Urban land cover categories. One point was removed from the NVA calculations due to drastic change in the area.</vertacce>
				</qvertpa>
				<qvertpa>
					<vertaccv>0.140</vertaccv>
					<vertacce>Tested 0.140 meters (0.458 feet) VVA was calculated using 35 checkpoints located in the Forested, Shrubs, and Tall Weeds land cover categories at the 95th percentile, derived according to ASPRS Guidelines, Vertical Accuracy Reporting for Lidar Data. Tested against the DEM.</vertacce>
				</qvertpa>
			</vertacc>
		</posacc>
		<lineage>
			<procstep>
				<procdesc>Hydro Flattened Raster DEM Process: Class 2 (Ground) lidar points in conjunction with the hydro breaklines were used to create a 2.5 foot hydro-flattened raster DEM. Using automated scripting routines within ArcMap, an ERDAS Imagine .IMG file was created for each tile. Each surface is reviewed using Global Mapper to check for any surface anomalies or incorrect elevations found within the surface.</procdesc>
				<procdate>2016</procdate>
			</procstep>
		</lineage>
	</dataqual>
	<spdoinfo>
		<direct>Raster</direct>
		<rastinfo>
			<rasttype>Pixel</rasttype>
			<rowcount>2000</rowcount>
			<colcount>2000</colcount>
		</rastinfo>
	</spdoinfo>
	<spref>
		<horizsys>
			<planar>
				<gridsys>
					<gridsysn>State Plane Coordinate System 1983</gridsysn>
					<spcs>
						<spcszone>2301</spcszone>
						<transmer>
							<sfctrmer>0.99995</sfctrmer>
							<longcm>-88.83333333333333</longcm>
							<latprjo>29.5</latprjo>
							<feast>984250.0</feast>
							<fnorth>0.0</fnorth>
						</transmer>
					</spcs>
				</gridsys>
				<planci>
					<plance>coordinate pair</plance>
					<coordrep>
						<absres>2.5</absres>
						<ordres>2.5</ordres>
					</coordrep>
					<plandu>survey feet</plandu>
				</planci>
			</planar>
			<geodetic>
				<horizdn>North American Datum of 1983 (2011)</horizdn>
				<ellips>Geodetic Reference System 80</ellips>
				<semiaxis>6378137.0</semiaxis>
				<denflat>298.257222101</denflat>
			</geodetic>
		</horizsys>
		<vertdef>
			<altsys>
				<altdatum>North American Vertical Datum of 1988 (GEOID12B)</altdatum>
				<altres>0.01</altres>
				<altunits>feet</altunits>
				<altenc>Explicit elevation coordinate included with horizontal coordinates</altenc>
			</altsys>
		</vertdef>
	</spref>
	<metainfo>
		<metd>20170126</metd>
		<metc>
			<cntinfo>
				<cntorgp>
					<cntorg>Quantum Spatial</cntorg>
				</cntorgp>
				<cntaddr>
					<addrtype>mailing and physical</addrtype>
					<address>523 Wellington Way</address>
					<city>Lexington</city>
					<state>KY</state>
					<postal>40503</postal>
					<country>USA</country>
				</cntaddr>
				<cntvoice>859-277-8700</cntvoice>
			</cntinfo>
		</metc>
		<metstdn>FGDC Content Standard for Digital Geospatial Metadata</metstdn>
		<metstdv>FGDC-STD-001-1998</metstdv>
	</metainfo>
</metadata>