Identification_Information: Citation: Citation_Information: Originator: U. S. Geological Survey, FISC St. Petersburg Publication_Date: Fall 2007 Title: EAARL Topography-Gulf Islands National Seashore-Mississippi Edition: First Geospatial_Data_Presentation_Form: vector digital data Series_Information: Series_Name: Open File Report Issue_Identification: 2007-1377 Publication_Information: Publication_Place: St. Petersburg, FL Publisher: U. S. Geological Survey Other_Citation_Details: The U. S. Geological Survey, in cooperation with the National Park Service (NPS) and the National Aeronautics and Space Administration (NASA), is to provide the coastal management community with usable, useful digital elevation products. The USGS processes aircraft Lidar data (provided by NASA), develops software tools and algorithms to use and analyze the data and make products available to the coastal management community through a variety of media, including the internet, CD-ROMs, DVDs and data reports. Online_Linkage: none Larger_Work_Citation: Citation_Information: Series_Information: Publication_Information: Description: Abstract: Abstract: Elevation maps (also known as Digital Elevation Models or DEMs) of Gulf Islands National Seashore were produced from remotely-sensed, geographically-referenced elevation measurements in cooperation with NASA and NPS. Point data in ascii text files were interpolated in a GIS to create a grid or digital elevation model (DEM) of each beach surface. Elevation measurements were collected in Florida, Mississippi and Texas, over Gulf Islands National Seashore, using the NASA Experimental Advanced Airborne Research Lidar (EAARL), a pulsed laser ranging system mounted onboard an aircraft to measure ground elevation and coastal topography. The system uses high frequency laser beams directed at the earth's surface through an opening in the bottom of the aircraft's fuselage. The laser system records the time difference between emission of the laser beam and the reception of the reflected laser signal in the aircraft. The plane travels over the beach at approximately 60 meters per second while surveying from the low-water line to the landward base of the sand dunes. The EAARL, developed by the National Aeronautics and Space Administration (NASA) located at Wallops Flight Facility in Virginia, measures ground elevation with a vertical resolution of 15 centimeters. A sampling rate of 3 kHz or higher results in an extremely dense spatial elevation data set. Over 100 kilometers of coastline can be easily surveyed within a 3- to 4-hour mission time period. The ability to sample large areas rapidly and accurately is especially useful in morphologically dynamic areas such as barrier beaches. Quick assessment of topographic change can be made following storms comparing measurements against baseline data. When subsequent elevation maps for an area are analyzed, they provide a useful tool to make management decisions regarding coastal development. Purpose: One goal of the Project is to produce highly detailed and accurate digital elevation maps (DEMs) of National Seashores and coastal parks for use as a management tool and to make these maps available to natural resource managers within the parks. Supplemental_Information: Raw Lidar data is not in a format that is generally usable by Park Service resource managers and scientists for scientific analysis. Converting dense Lidar elevation data into a readily usable format without loss of essential information requires specialized processing. The U. S. Geological Survey converts raw Lidar data into a GIS-compatible map product to be provided to Park Service GIS specialists, managers, and scientists. The primary tool used in the conversion process is Airborne Lidar Processing System (ALPS), a multitiered processing system developed by a USGS/NASA collaborative for the use of topographic Lidar in coastal change assessment. Specialized processing algorithms are used to convert raw waveform Lidar data acquired by the EAARL to georeferenced spot (x,y,z) returns for "first surface" and "bare earth" topography. These data are then converted to the NAD83 horizontal and NAVD88 vertical datum (using the Geoid 99 model). The final products are 2x2-km map tiles written out in a standard geotiff format with associated metadata information. These tiles are created for visual interpretation and regional quantitative analysis. Metadata files include the standard FGDC format. Supplemental_Information: See the source Lidar GeoTIFF tile for more specific accuracy information. Time_Period_of_Content: Time_Period_Information: Multiple_Dates/Times: Single_Date/Time: Calendar_Date: 20050901, 20050903, 20050904, 20050907, 20050908 Currentness_Reference: ground condition Status: Progress: Complete Maintenance_and_Update_Frequency: Unknown Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: East_Bounding_Coordinate: North_Bounding_Coordinate: South_Bounding_Coordinate: Keywords: Theme: Theme_Keyword_Thesaurus: NONE Theme_Keyword: Lidar Theme_Keyword: Experimental Advanced Airborne Research Lidar Theme_Keyword: digital elevation model Theme_Keyword: elevation change Theme_Keyword: laser altimetry Theme_Keyword: derived surface Theme_Keyword: resource management Theme_Keyword: bare earth elevation Theme_Keyword: ALPS Theme_Keyword: Airborne Lidar Processing System Place: Place_Keyword: Gulf Islands National Seashore Place_Keyword: Mississippi Place_Keyword: Gulf of Mexico Stratum: Stratum_Keyword: bare earth topography Temporal: Access_Constraints: Any use of these data signifies a user's agreement to comprehension and compliance of the U. S. Geological Survey's Standard Disclaimer. Ensure all portions of metadata are read and clearly understood before using these data in order to protect both user and USGS interests. See section 6.3 Distribution Liability. Use_Constraints: Although the U. S. Geological Survey is making these data sets available to others who may find the data of value, the U. S. Geological Survey does not warrant, endorse, or recommend the use of these data setse for any given purpose. The user assumes the entire risk related to the use of these data. These data sets are not for navigational purposes. The U. S. Geological Survey is providing these data "as is", and the U. S. Geological Survey disclaims any and all warranties, whether expressed or implied, including (without limitation) any implied warranties of merchantability or fitness for a particular purpose. In no event will the USGS be liable to you or to any third party for any direct, indirect, incidental, consequential, special, or exemplary damages or lost profits resulting from any use or misuse of these data. Acknowledgement of the U.S. Geological Survey, FISC St. Petersburg office, as a data source would be appreciated in products developed from these data, and such acknowledgement as is standard for citation and legal practices for data source is expected by users of this data. Sharing new data layers developed directly from these data would also be appreciated by the USGS staff. Users should be aware that comparisons with other data sets for the same area from other time periods may be inaccurate due to inconsistencies resulting from changes in photo interpretation, mapping conventions, and digital processes over time. These data are not legal documents and are not to be used as such. Point_of_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U. S. Geological Survey, FISC St. Petersburg 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: 8:30-5:00 M-F EST Contact_Instructions: Call Survey for Details Browse_Graphic: Data_Set_Credit: The U. S. Geological Surveyy, FISC St. Petersburg office, would like to acknowledge NASA Goddard Space Flight Center for their cooperation and assistance in the development of the data. The USGS would also like to acknowledge National Park Service management and personnel at Gulf Islands National Seashore. Security_Information: Security_Classification: Unclassified Native_Data_Set_Environment: Microsoft Windows XP Version 5.1 (Build 2600) Service Pack 2; ESRI ArcMap 9.2.0 1324 Data_Quality_Information: Attribute_Accuracy: Attribute_Accuracy_Report: The expected accuracy of the measured variables is as follows: attitude within 0.07 degree, 3-cm nominal ranging accuracy, and verticle elevation accuracy of +/- 15cm (bare earth). Quality checks are built into the data-processing software. Logical_Consistency_Report: This layer was generated from an existing Lidar tile. Completeness_Report: Contour lines break where there was no data (value of -100) in the original Lidar tiles. Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: Raw elevation measurements have been determined to be within 1.5 meter horizontal accuracy. Processing steps (grid interpolation) may introduce additional error which has not been tested at the time of this publication. Vertical_Positional_Accuracy: Vertical_Positional_Accuracy_Report: Elevations of the DEM are vertically consistent with the point elevation data, +/- 15cm. Lineage: Source_Information: Type_of_Source_Media: computer program Source_Time_Period_of_Content: Time_Period_Information: Multiple_Dates/Times: Single_Date/Time: Calendar_Date: 20050901, 20050903, 20050904, 20050907, 20050908 Source_Currentness_Reference: ground condition Process_Step: Process_Description: The Lidar GeoTIFF data was too coarse to create aesthetically pleasing contours. A Neighborhood Statistics operation was run on the Lidar GeoTIFF file in ArcMap. The settings for the Neighborhood Statistics operation were a 14x14 cell rectangle, using the mean as the statistic type and then output to a temporary raster grid. Process_Date: Spring 2007 Process_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: National Park Service South Florida/Caribbean Network Contact_Person: Iris Wilson Contact_Position: Research Assistant Contact_Address: Address_Type: mailing and physical address Address: 18001 Old Cutler Road City: Palmetto Bay State_or_Province: FL Postal_Code: 33157 Country: USA Contact_Voice_Telephone: (305) 252-0347 Hours_of_Service: 8:30-5:00 M-F EST Process_Step: Process_Description: Contour lines were generated using the Contour operation in ArcMap. The temporary Neighborhood Statistics grid was used as the input surface and the contour interval was set to 1 (meter). This was output to a permanent shapefile. Process_Date: Spring 2007 Process_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: National Park Service South Florida/Caribbean Network Contact_Person: Iris Wilson Contact_Position: Research Assistant Contact_Address: Address_Type: mailing and physical address Address: 18001 Old Cutler Road City: Palmetto Bay State_or_Province: FL Postal_Code: 33157 Country: USA Contact_Voice_Telephone: (305) 252-0347 Hours_of_Service: 8:30-5:00 M-F EST Process_Step: Process_Description: Metadata imported into ArcCatalog from XML file. Process_Date: 2070829 Process_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U. S. Geological Surveyy, FISC St. Petersburg 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: 8:30-5:00 M-F EST Spatial_Data_Organization_Information: Direct_Spatial_Reference_Method: Vector Point_and_Vector_Object_Information: SDTS_Terms_Description: 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: 0.999600 Longitude_of_Central_Meridian: -75.000000 Latitude_of_Projection_Origin: 0.000000 False_Easting: 500000.000000 False_Northing: 0.000000 Planar_Coordinate_Information: Planar_Coordinate_Encoding_Method: row and column Coordinate_Representation: Abscissa_Resolution: 1.000000 Ordinate_Resolution: 1.000000 Planar_Distance_Units: meters Geodetic_Model: Horizontal_Datum_Name: North American Datum of 1983 Ellipsoid_Name: Geodetic Reference System 80 Semi-major_Axis: 6378137.000000 Denominator_of_Flattening_Ratio: 298.257222 Vertical_Coordinate_System_Definition: Altitude_System_Definition: Altitude_Datum_Name: North American Vertical Datum of 1988 Altitude_Resolution: .15 Altitude_Distance_Units: meters Altitude_Encoding_Method: Explicit elevation coordinate included with horizontal coordinates Entity_and_Attribute_Information: Overview_Description: Distribution_Information: Distributor: Contact_Information: Contact_Organization_Primary: Contact_Organization: United States Geological Survey, FISC St. Petersburg 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: 8:30-5:00 M-F EST Contact_Instructions: Call U. S. Geological Survey for Details Distribution_Liability: The U. S. Geological Survey gives no warranty, expressed or implied, as to the accuracy, reliability, or completeness of these data. It is strongly recommended that these data are directly acquired from a USGS server and not indirectly through other sources which may have changed the data in some way. Although these data have been processed successfully on a computer system at the U. S. Geological Survey, no warranty expressed or implied is made regarding the utility of the data on another system or for general or scientific purposes, nor shall the act of distribution constitute any such warranty. This disclaimer applies both to individual use of the data and aggregate use with other data. Standard_Order_Process: Digital_Form: Digital_Transfer_Information: Transfer_Size: 0.000 Ordering_Instructions: Call U. S. Geological Survey for Details Custom_Order_Process: Call U. S. Geological Survey for Details Available_Time_Period: Time_Period_Information: Multiple_Dates/Times: Single_Date/Time: Calendar_Date: 20050901, 20050903, 20050904, 20050907, 20050908 Metadata_Reference_Information: Metadata_Date: 20070829 Metadata_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: UU. S. Geological Survey, FISC St. Petersburg 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: 8:30-5:00 M-F EST Contact_Instructions: Call Survey for Details Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata Metadata_Standard_Version: FGDC-STD-001-1998 Metadata_Time_Convention: local time Metadata_Security_Information: Metadata_Security_Classification: Unclassified