A DEM was produced for a portion of the New York, Delaware, Maryland, Virginia, and North Carolina coastlines, post-Hurricane Sandy (Sandy was an October 2012 hurricane that made landfall as an extratropical cyclone on the 29th), from remotely sensed, geographically referenced elevation measurements collected by Photo Science, Inc. (Delaware, Maryland, Virgina, and North Carolina) and Woolpert, Inc. (Fire Island, New York) using airborne lidar sensors.

A topographic lidar survey was conducted on July 12-14, 2013 over Dauphin Island, Alabama and Chandeleur, Stake, Grand Gosier and Breton Islands, Louisiana. The data were collected at a nominal pulse space of 1 meter (m) and processed to identify bare earth elevations. Bare earth Digital Elevation Models (DEMs) were generated based on these data. Photo Science, Inc., was contracted by the U.S. Geological Survey (USGS) to collect and process the lidar data. The bare earth DEMs are 32-bit floating point ERDAS Imagine (IMG) files with a horizontal spatial resolution of 1-m by 1-m. They are projected to Universal Transverse Mercator (UTM), Zone 16, North American Datum (NAD) 1983, meters (m) coordinates. Their vertical datum is NAVD88 (GEOID12A) meters. Eighty-five DEMs, based on a 2-kilometer (km) by 2-km tiling scheme, cover the entire survey area. These lidar data are available to Federal, State and local governments, emergency-response officials, resource managers, and the general public.

A topographic lidar survey was conducted July 12-14, 2013 over Dauphin Island, Alabama and Chandeleur, Stake, Grand Gosier and Breton Islands, Louisiana. Lidar data exchange format (LAS) 1.2 formatted classified point data files were generated based on these data. Photo Science, Inc. was contracted by the U.S. Geological Survey (USGS) to collect and process the lidar data. The lidar data were collected at a nominal pulse spacing (NPS) of 1.0 meter (m). The horizontal projection and datum of the data are Universe Transverse Mercator, zone 16N, North American Datum 1983 (UTM Zone 16N NAD83), meters. The vertical datum is North American Vertical Datum 1988, Geoid 2012a (NAVD88, GEOID12A), meters. Eighty-five LAS files, based on a 2-kilometer by 2-kilometer tiling scheme, cover the entire survey area. These lidar data are available to Federal, State and local governments, emergency-response officials, resource managers, and the general public. Lidar_Information Lidar_Collection_Information Lidar_Specification USGS-NGP Base Lidar Specification v1.0 Lidar_Sensor Leica ALS 70 Lidar_Maximum_Returns 4 Lidar_Pulse_Spacing 0.64 Lidar_Density 1.57 Lidar_Flight_Height 1524 Lidar_Flight_Speed 130 Lidar_Scan_Angle 20.0 Lidar_Scan_Frequency 29.6 Lidar_Pulse_Rate 178.4 Lidar_Pulse_Duration 4 Lidar_Pulse_Width 0.35 Lidar_Central_Wavelength 1064 Lidar_Multiple_Pulses_In_Air 0 Lidar_Beam_Divergence 0.22 Lidar_Swath_Width 1109.38 Lidar_Swath_Overlap 11.46% Lidar_Coordinate_Reference_System_Name NAD_1983_UTM_Zone_16N_Meters Lidar_Geoid National Geodetic Survey (NGS) Geoid03 Lidar_Accuracy_Information Lidar_Calculated_Horizontal_Accuracy 0.012 Lidar_Raw_Fundamental_Vertical_Accuracy 0.01 Lidar_LAS_Information Lidar_LAS_Version 1.2 Lidar_LAS_Point_Record_Format 1 Lidar_LAS_Witheld_Point_Identifier Withheld (ignore) points were identified in these files using the standard LAS Withheld bit. Lidar_LAS_Overage_Point_Identifier Swath "overage" points were identified in these files by adding 16 to the standard classification values. Lidar_LAS_Radiometric_Resolution 8 Lidar_LAS_Classification Lidar_LAS_Class_Code 1 Lidar_LAS_Class_Description Processed, but unclassified Lidar_LAS_Classification Lidar_LAS_Class_Code 2 Lidar_LAS_Class_Description Bare earth ground Lidar_LAS_Classification Lidar_LAS_Class_Code 7 Lidar_LAS_Class_Description Noise Lidar_LAS_Classification Lidar_LAS_Class_Code 9 Lidar_LAS_Class_Description Water Lidar_LAS_Classification Lidar_LAS_Class_Code 10 Lidar_LAS_Class_Description Ignored ground Lidar_LAS_Classification Lidar_LAS_Class_Code 17 Lidar_LAS_Class_Description Overlap default (unclassified) Lidar_LAS_Classification Lidar_LAS_Class_Code 18 Lidar_LAS_Class_Description Overlap bare-earth ground

A topographic lidar survey was conducted from September 5 to October 11, 2012, for the barrier islands of Alabama, Mississippi and southeast Louisiana, including the coast near Port Fourchon. Most of the data were collected September 5-10, 2012, with a reflight conducted on October 11, 2012, to increase point density in some areas. The data were collected at a nominal pulse space of 1-meter (m) and processed to identify bare earth elevations. Bare earth Digital Elevation Models(DEMs) were generated based on these data. Aero-Metric, Inc., was contracted by the U.S. Geological Survey (USGS) to collect and process the lidar data. The bare earth DEMs are 32-bit floating point ERDAS Imagine (IMG) files with a horizontal spatial resolution of 1-m by 1-m. They are projected to UTM zone 15N or 16N NAD83 meters. Their vertical datum is NAVD88 (GEOID12) meters. The DEMs are organized on a 2-kilometer (km) by 2-km tiling scheme that covers the entire survey area. These lidar data are available to Federal, State and local governments, emergency-response officials, resource managers, and the general public.

This Data Series Report contains lidar elevation data collected February 6, 2012, over the Chandeleur Islands, Louisiana. LAS 1.2 formatted point data files were generated based on these data. The point cloud data were processed to extract bare earth data; therefore, the point cloud data are classified into only these classes: 1 and 17-unclassified, 2-ground, 9-water, and 10-breakline proximity. Digital Aerial Solutions, LLC, was contracted by the USGS to collect and process these data. The lidar data were collected at a nominal pulse spacing (NPS) of 0.5 meter (m). The data are in decimal degree geographic coordinates, North American Datum 1983, National Spatial Reference System 2007 (NAD83 NSRS2007)). The vertical datum is North American Vertical Datum 1988, Geoid 2009, Geodetic Reference System 1980 (NAVD88 GEOID09 GRS80) in meters. Thirty-three LAS files, based on a 2-kilometer by 2-kilometer tiling scheme, cover the entire survey area. These lidar data are available to Federal, State and local governments, emergency-response officials, resource managers, and the general public.