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<attribute type="string" name="fgdc_id" value="gov.noaa.csc.maps:utexas_2002"/>
<attribute type="string" name="fgdc_title" value="2002 Upper Texas Coast Lidar Point Data, Gulf of Mexico Shoreline in the Northeast 3.75-Minute Quadrant of the Lake Como 7.5-Minute Quadrangle: Post Fay Survey"/>
<attribute type="string" name="fgdc_summary" value="This data set contains elevation data derived from a lidar survey approximately 300m wide of the Gulf of Mexico shoreline in the Northeast Lake Como quarter-quadrangle on Galveston Island Texas. The geographic extent of the data set is equivalent to the quarter-quadrangle plus 30 meters of overedge. The data is created by combining data collected using an Optech Inc. Airborne Laser Terrain Mapper (ALTM) 1225 in combination with geodetic quality Global Positioning System (GPS) airborne and ground-based receivers. The Bureau of Economic Geology, the University of Texas at Austin owns and operates an ALTM 1225 system (serial number 99d118). This system is installed in a single engine Cessna 206 (tail number N4589U) owned and operated by the Texas State Aircraft Pooling Board. The lidar data described by this document was collected on 18 September 2002 (26102) between 20:34 and 00:08 UTC (actual data collection). Conditions on that day were low clouds at 335m Above Ground Level (AGL), haze, and occasional showers. 99d118 instrument settings for this flight were; laser pulse rate: 25kHz, scanner rate: 26Hz, scan angle: +/-20deg, beam divergence: wide, altitude: 300-490m AGL, and ground speed: 70-106kts. Three GPS base stations, 2 Ashtech and 1 Trimble 4000SSI receivers (backup), were operating during the survey. The three base stations were at the following locations: one 3.5km south of San Luis Pass, one at the Scholes International Airport Galveston, and one on the seawall at Rollover Pass. This data set consists of 1687100 records of x,y, and z values. The data set was generated from a larger data set and includes all valid points within the requested geographic bounds."/>
<attribute type="string" name="fgdc_keywords" value="EARTH SCIENCE &gt; LAND SURFACE &gt; Topography &gt; Terrain Elevation, lidar, laser, beach, topography, digital elevation model, DEM, erosion"/>
<attribute type="string" name="fgdc_keywords_vocabulary" value="GCMD, None"/>
<attribute type="string" name="fgdc_comment" value="The ALTM 1225 has the following specifications: operating altitude = 410-2,000 m AGL; laser pulse rate = 25 kHz; laser scan angle = variable from 0 to +/-20deg from nadir; scanning frequency = variable, 28 Hz at the 20deg scan angle; and beam divergence = 0.2 milliradian (half angle, 1/e). The ALTM 1225 does not digitize and record the waveform of the laser reflection, but records the range and backscatter intensity of the first and last laser reflection using a constant-fraction discriminator and two Timing Interval Meters (TIM). ALTM elevation points are computed using three sets of data: laser ranges and their associated scan angles, platform position and orientation information, and calibration data and mounting parameters (Wehr and Lohr, 1999). Global Positioning System (GPS) receivers in the aircraft and on the ground provide platform positioning. The GPS receivers record pseudo-range and phase information for post-processing. Platform orientation information comes from an Inertial Measurement Unit (IMU) containing three orthogonal accelerometers and gyroscopes. An aided-Inertial Navigation System (INS) solution for the aircraft's attitude is estimated from the IMU output and the GPS information. Wehr, A. and U. Lohr, 1999, Airborne laser scanning - an introduction and overview, ISPRS Journal of Photogrammetry and Remote Sensing, vol. 54, no.2-3, pp.68-82."/>
<attribute type="string" name="fgdc_creator_name" value="Jim Gibeaut"/>
<attribute type="string" name="fgdc_creator_email" value="jim.gibeaut@beg.utexas.edu"/>
<attribute type="string" name="fgdc_institution" value="Bureau of Economic Geology University of Texas at Austin"/>
<attribute type="string" name="fgdc_license" value="ACCESS CONSTRAINTS: None, USE CONSTRAINTS: These data were collected for the purpose of determining amounts and rates of shoreline change along the Upper Gulf of Mexico coast of Texas following Tropical Storm Fay, September 2002. Any conclusions drawn from analysis of this information are not the responsibility of the Bureau of Economic Geology or the University of Texas at Austin or the NOAA Coastal Services Center., DISTRIBUTION LIABILITY: This data was collected for the purpose of determining amounts and rates of shoreline change along the Upper Gulf of Mexico coast of Texas following Tropical Storm Fay, September 2002. Any conclusions drawn from analysis of this information are not the responsibility of the Bureau of Economic Geology or the University of Texas at Austin or the NOAA Coastal Services Center."/>
<attribute type="string" name="fgdc_publisher_name" value="NOAA Coastal Services Center"/>
<attribute type="string" name="fgdc_publisher_email" value="csc@csc.noaa.govkelly.stroker@noaa.gov"/>
<attribute type="string" name="fgdc_metadata_contact" value="Keil Schmid, NOAA Coastal Services Center"/>
<attribute type="string" name="fgdc_update_frequency" value="None planned, as needed"/>
<attribute type="string" name="fgdc_progress" value="Complete"/>
<attribute type="string" name="metadata_conventions" value="Content Standard for Digital Geospatial Metadata: Extensions for Remote Sensing Metadata"/>
<attribute type="string" name="fgdc_metadata_url" value="http://www.ngdc.noaa.gov/nmmrview/fgdc.jsp?id=gov.noaa.csc.maps:utexas_2002&amp;view=xml&amp;responseType=text/plain"/>
<attribute type="int" name="fgdc_date_created" value="20061017"/>
<attribute type="int" name="fgdc_date_issued" value="20061017"/>
<attribute type="float" name="fgdc_geospatial_lat_min" value="28.797218"/>
<attribute type="float" name="fgdc_geospatial_lat_max" value="29.688483"/>
<attribute type="float" name="fgdc_geospatial_lon_min" value="-93.831419"/>
<attribute type="float" name="fgdc_geospatial_lon_max" value="-95.568694"/>
<attribute type="int" name="fgdc_time_coverage_start" value=""/>
<attribute type="int" name="fgdc_time_coverage_end" value=""/>
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