Metadata: Identification_Information: Citation: Citation_Information: Originator: U.S. Geological Survey Publication_Date: 2013 Title: Topographic Lidar Survey of the Alabama, Mississippi, and Southeast Louisiana Barrier Islands, from September 5 to October 11, 2012 -- Bare Earth Digital Elevation Models Geospatial_Data_Presentation_Form: remote-sensing image Series_Information: Series_Name: U.S. Geological Survey Data Series Issue_Identification: 839 Publication_Information: Publication_Place: St. Petersburg, Fla. Publisher: U.S. Geological Survey Online_Linkage: http://pubs.usgs.gov/ds/839 Description: Abstract: 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. Purpose: This lidar survey was acquired to document the change of several different barrier island systems resulting from Hurricane Isaac. The survey supports detailed studies of Louisiana, Mississippi and Alabama barrier islands that resolve annual and episodic changes in beaches, berms and dunes associated with processes driven by storms, sea-level rise, and even human restoration activities. Supplemental_Information: Lidar data acquisition, calibration, and follow-on processing were completed by Aero-Metric, Inc. Aero-Metric was contracted by the USGS to conduct the work. The file naming convention is based on a 2-km by 2-km tiling scheme. The geographic extent of each tile falls on even 2000 x and y coordinates in UTM zone 15N or 16N, NAD83, meters. The first two digits of the file name represent the UTM zone. The last eight digits are based on the lower-left (LL) xy coordinate of the tile. For example, tile name 15_69802160 uses 6980 to represent an LL x-coordinate of 698,000, and uses 2160 to represent an LL y-coordinate of 3,216,000 (ignoring the first digit). Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 20120905 Ending_Date: 20121011 Currentness_Reference: ground condition Status: Progress: Complete Maintenance_and_Update_Frequency: None planned Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -90.975 East_Bounding_Coordinate: -88.055 North_Bounding_Coordinate: 30.266 South_Bounding_Coordinate: 29.020 Keywords: Theme: Theme_Keyword_Thesaurus: None Theme_Keyword: model Theme_Keyword: remote sensing Theme_Keyword: elevation data Theme_Keyword: lidar Theme_Keyword: Digital Elevation Model Theme_Keyword: DEM Theme_Keyword: topography Theme_Keyword: hydrology Theme_Keyword: laser altimetry Theme_Keyword: bare earth Theme: Theme_Keyword_Thesaurus: Global Change Master Science Directory (GCMD) Theme_Keyword: LAND SURFACE > TOPOGRAPHY > TERRAIN ELEVATION Theme_Keyword: OCEAN > COASTAL PROCESSES > BARRIER ISLANDS Theme_Keyword: COASTAL PROCESSES > BEACHES Theme_Keyword: DOI/USGS/CMG > COASTAL AND MARINE GEOLOGY, U.S. GEOLOGICAL SURVEY, U.S. DEPARTMENT OF INTERIOR Theme_Keyword: Digital Elevation Model Theme: Theme_Keyword_Thesaurus: GCMD Instrument Theme_Keyword: LIDAR > LIGHT DETECTION AND RANGING Place: Place_Keyword_Thesaurus: None Place_Keyword: Alabama Place_Keyword: Mississippi Place_Keyword: Louisiana Place_Keyword: Gulf of Mexico Place_Keyword: Barrier Islands Place_Keyword: Gulf of Mexico Barrier Islands Place_Keyword: Raccoon Island Place_Keyword: Trinity Island Place_Keyword: Isles Dernieres Place_Keyword: Timbalier Island Place_Keyword: East Timbalier Island Place_Keyword: Port Fourchon Place_Keyword: Elmers Island Place_Keyword: Grand Isle Place_Keyword: Grand Terre Island Place_Keyword: Bastian Island Place_Keyword: Pelican Island Place_Keyword: Stake Island Place_Keyword: Grand Gosier Island Place_Keyword: Breton Island Place_Keyword: Chandeleur Islands Place_Keyword: Cat Island Place_Keyword: Ship Island Place_Keyword: Horn Island Place_Keyword: Petit Bois Island Place_Keyword: Dauphin Island Place_Keyword: United States Temporal: Temporal_Keyword_Thesaurus: General Temporal_Keyword: 2012 Access_Constraints: None. Use_Constraints: None. However, users should be aware that temporal changes may have occurred since this dataset was collected and some parts of this data may no longer represent surface conditions. Users should not use this data for critical applications without a full awareness of its limitations. Acknowledgment of the U.S. Geological Survey would be appreciated for products derived from these data. Point_of_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Person: Nathaniel Plant Contact_Address: Address_Type: mailing and physical Address: 600 4th St. S. City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Country: USA Contact_Voice_Telephone: 727-803-8747 Contact_Facsimile_Telephone: 727-803-2031 Contact_Electronic_Mail_Address: nplant@usgs.gov Hours_of_Service: Monday through Friday 9:00 AM to 5:00 PM (Eastern Time) Dataset_Credit: Acknowledgment of the U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center, as a data source would be appreciated in products developed from these data, and such acknowledgment as is standard for citation and legal practices. Sharing of new data layers developed directly from these data would also be appreciated by the U.S. Geological Survey staff. Users should be aware that comparisons with other datasets for the same area from other time periods may be inaccurate due to inconsistencies resulting from changes in photointerpretation, mapping conventions, and digital processes over time. These data are not legal documents and are not to be used as such. Native_Dataset_Environment: Contractor: Aero-Metric, Inc. 1. Scanner - Optech 3100 Serial 05SEN175 and Leica ALS70 SN7169 2. Processing Programs and versions - Applanix - POSGPS and POSProc, versions 4.4, MMS version 5.2 3. Program and version - Optech ASDA 4. Processing Programs and versions - TerraSolid TerraScan (version 012.016), TerraModeler (version 012.008) and TerraMatch (version 012.009), Intergraph MicroStation (version 08.05.02.55), and GeoCue (version 2011.1.20.4). 5. Viewing Program - GlobalMapper V13.00 Data_Quality_Information: Logical_Consistency_Report: The classified lidar data exchange format (LAS) files were tested by Aero-Metric for vertical and horizontal accuracy. Completeness_Report: Complete. Positional_Accuracy: Vertical_Positional_Accuracy: Vertical_Positional_Accuracy_Report: The USGS conducted ground surveys in a small area on Chandeleur Island on September 6, 2012, one on bare earth and another in mixed bare earth and vegetated areas. The USGS calculated a vertical root mean square error (RMSEz) of 0.072 m and an offset of 0.007 m using interpolated 2-m by 2-m resolution grid surfaces made from lidar bare-earth data and combined USGS ground surveys. The contractor was required to achieve a fundamental vertical accuracy (FVA) of 24.5 centimeters (cm), 95 percent (12.5 cm RMSEz); a consolidated vertical accuracy (CVA) of 36.3 cm, 95th percentile; and a target value for supplemental vertical accuracies (SVA) of 36.3 cm, 95th percentile. Aero-Metric's vertical accuracy assessment was as follows: The FVA of the LAS Swath Data achieved 5.0 cm at a 95 percent confidence level with an RMSE of 2.5 cm utilizing (2280) ground survey check points provided by the USGS. The SVA results in an area of open terrain achieved 4.8 cm at the 95th percentile where (2280) ground survey check points provided by the USGS were evaluated. The SVA results in an area of vegetation achieved 10.7 cm at the 95th percentile where (2421) ground survey check points provided by the USGS were evaluated. The CVA results for all land cover classes, ground and vegetation combined, achieved 7.3 cm at the 95th percentile where (4700) checkpoints were evaluated. The USGS also conducted a terrestrial lidar survey on Dauphin Island, Louisiana, on September 3, 2012. The USGS calculated an RMSEz of 0.32 m and an offset of 0.27 m using interpolated 2-m by 2-m resolution grid surfaces from the airborne lidar bare-earth data and the terrestrial lidar survey. Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: Area data products collected with the Optech 3100 or Leica ALS70 were acquired at or below 1200 m above mean terrain (AMT) and have a horizontal accuracy of 0.218 m (per manufacturers system specifications), with a nominal point spacing of 1.0 m. Lineage: Source_Information: Source_Citation: Citation_Information: Originator: Aero-Metric, Inc. Publication_Date: 20130124 Title: Lidar RAW Data for Gulf of Mexico Barrier Islands Geospatial_Data_Presentation_Form: lidar data Publication_Information: Publication_Place: Aero-Metric, Inc. Publisher: Aero-Metric, Inc. Aerial LiDAR Department Type_of_Source_Media: digital hard drive Source_Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 20120905 Ending_Date: 20121011 Source_Currentness_Reference: ground condition Source_Citation_Abbreviation: Raw Lidar Data Source_Contribution: This data source was used to populate the lidar point cloud data. This dataset is not included in this Data Series Report. Source_Information: Source_Citation: Citation_Information: Originator: U.S. Geological Survey Publication_Date: 2012 Title: Ground Control Points Type_of_Source_Media: digital hard drive Source_Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 20120903 Ending_Date: 20120906 Source_Currentness_Reference: ground condition Source_Citation_Abbreviation: Ground Control Points Source_Contribution: This data source was used in lidar processing and accuracy assessment. This dataset is not included in this Data Series Report. Process_Step: Process_Description: Lidar Pre-Processing: The point cloud data was imported to TerraScan in a Microstation V8 (V) CAD environment on a specified 2000 m by 2000 m tiling scheme. The data were analyzed for overall completeness and consistency. The data were then inspected for calibration errors with TerraMatch software. This was accomplished by sampling the data collected across all flight lines and classifying the individual lines to ground. The software used the ground-classified lines to compute calibration corrections (heading, pitch, roll, and scale) that were applied to the dataset. USGS ground surveys from a small area on Chandeleur Islands, Louisiana, were used to test the accuracy of the lidar ground surface. TerraScan's Output Control Report (OCR) was used to compare the quality assurance/quality control (QA/QC) data to the lidar data. This routine searches the lidar dataset by x,y coordinates, finds the closest lidar point and compares the vertical (z) values to the known data collected in the ground survey. Based on the QA/QC data, necessary bias adjustments were made to the lidar data. Source_Used_Citation_Abbreviation: Raw Lidar Data Source_Used_Citation_Abbreviation: Ground Control Points Process_Date: 20121001 Source_Produced_Citation_Abbreviation: Calibrated Lidar Datasets Process_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: Aero-Metric, Inc. Contact_Address: Address_Type: mailing and physical Address: 4020 Technology Parkway City: Sheboygan State_or_Province: WI Postal_Code: 53083 Country: USA Contact_Voice_Telephone: 920-457-3631 Contact_Facsimile_Telephone: 920-457-4010 Process_Step: Process_Description: Lidar Ground Classification: Automatic ground classification was performed using algorithms with customized parameters to best fit the project area. Areas of varying relief and planimetric features were inspected to verify the ground classification. Each tile was reviewed for accuracy and consistency. Source_Used_Citation_Abbreviation: Calibrated Lidar Datasets Process_Date: 20121001 Source_Produced_Citation_Abbreviation: Classified Lidar Datasets Process_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: Aero-Metric, Inc. Contact_Address: Address_Type: mailing and physical Address: 4020 Technology Parkway City: Sheboygan State_or_Province: WI Postal_Code: 53083 Country: USA Contact_Voice_Telephone: 920-457-3631 Contact_Facsimile_Telephone: 920-457-4010 Process_Step: Process_Description: The bare earth lidar points were used to generate ASCII formatted DEMs. The DEMs were reviewed for completeness and adherence to the tile layout used during creation. The files were converted to IMG format with ArcMap. Source_Used_Citation_Abbreviation: Classified Lidar Datasets Process_Date: 20121001 Source_Produced_Citation_Abbreviation: Raster DEMs Process_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: Aero-Metric, Inc. Contact_Address: Address_Type: mailing and physical Address: 4020 Technology Parkway City: Sheboygan State_or_Province: WI Postal_Code: 53083 Country: USA Contact_Voice_Telephone: 920-457-3631 Contact_Facsimile_Telephone: 920-457-4010 Spatial_Data_Organization_Information: Indirect_Spatial_Reference: Tile Index Direct_Spatial_Reference_Method: Raster Raster_Object_Information: Raster_Object_Type: Pixel Spatial_Reference_Information: Horizontal_Coordinate_System_Definition: Planar: Grid_Coordinate_System: Grid_Coordinate_System_Name: Universal Transverse Mercator Universal_Transverse_Mercator: UTM_Zone_Number: 16 Transverse_Mercator: Scale_Factor_at_Central_Meridian: 0.9996 Longitude_of_Central_Meridian: -87.000000 Latitude_of_Projection_Origin: 0.0 False_Easting: 500000 False_Northing: 0.0 Planar_Coordinate_Information: Planar_Coordinate_Encoding_Method: coordinate pair Coordinate_Representation: Abscissa_Resolution: 0.01 Ordinate_Resolution: 0.01 Planar_Distance_Units: meters Geodetic_Model: Horizontal_Datum_Name: North American Datum of 1983 Ellipsoid_Name: Geodetic Reference System 80 Semi-major_Axis: 6378137 Denominator_of_Flattening_Ratio: 298.257222101 Vertical_Coordinate_System_Definition: Altitude_System_Definition: Altitude_Datum_Name: North American Vertical Datum of 1988 Altitude_Resolution: 0.01 Altitude_Distance_Units: meters Altitude_Encoding_Method: Explicit elevation coordinate included with horizontal coordinates Entity_and_Attribute_Information: Overview_Description: Entity_and_Attribute_Overview: The bare earth DEMs are composed of single band, 1-m by 1-m resolution, 32-bit floating point continuous rasters in ERDAS Imagine format derived from bare earth classified lidar data. The vertical units are in meters, NAVD88, GEOID12. Entity_and_Attribute_Detail_Citation: USGS. 2013. Topographic Lidar Survey of the Alabama, Mississippi and Southeast Louisiana Barrier Islands, September 5 to October 11, 2012. Distribution_Information: Distributor: Contact_Information: Contact_Person_Primary: Contact_Person: Nathaniel Plant Contact_Organization: U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center, St. Petersburg, Fla. Contact_Position: Research Oceanographer Contact_Address: Address_Type: mailing and physical address Address: 600 4th Street South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Country: USA Contact_Voice_Telephone: 727-803-8747 Hours_of_Service: Monday-Friday, 9:00-5:00 Eastern Time Resource_Description: DS 839 Distribution_Liability: Although these data were processed successfully on a computer system at the USGS, no warranty expressed or implied is made regarding the display or utility of the data on any other system, or for general or scientific purposes, nor shall the act of distribution constitute any such warranty. The USGS shall not be held liable for improper or incorrect use of the data described and/or contained herein. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Standard_Order_Process: Digital_Form: Digital_Transfer_Information: Format_Name: LAS, zipped Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: http://pubs.usgs.gov/ds/839/data/ Fees: None if obtained online; otherwise prices vary. Ordering_Instructions: Publications are available from USGS Information Services, Box 25286, Federal Center, Denver, CO 80225-0046 (telephone: 1-888-ASK-USGS, e-mail: infoservices@usgs.gov). Metadata_Reference_Information: Metadata_Date: 20131112 Metadata_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Person: K. Guy Contact_Address: Address_Type: mailing and physical Address: 600 4th Street South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Country: USA Contact_Voice_Telephone: 727-803-8747 Contact_Facsimile_Telephone: 727-803-2031 Contact_Electronic_Mail_Address: kguy@usgs.gov Hours_of_Service: Monday through Friday 9:00 AM to 5:00 PM (Eastern Time) Metadata_Standard_Name: FGDC Content Standard for Digital Geospatial Metadata Metadata_Standard_Version: FGDC-STD-001-1998 Metadata_Access_Constraints: None. Metadata_Use_Constraints: None. Metadata_Security_Information: Metadata_Security_Classification_System: None. Metadata_Security_Classification: Unclassified Metadata_Security_Handling_Description: NONE