EAARL Topography-Gulf Islands National Seashore-Mississippi

Metadata:

• Identification_Information
• Data_Quality_Information
• Spatial_Data_Organization_Information
• Spatial_Reference_Information
• Entity_and_Attribute_Information
• Distribution_Information
• Metadata_Reference_Information

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

Geospatial_Data_Presentation_Form: vector digital data

Series_Information:

Series_Name: Open File Report

Issue_Identification: 2007-1377

Publication_Information:

Publication_Place: FISC St. Petersburg

Publisher: U. S. Geological Survey

Description:

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 the National Parks Service. 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 and Mississippi, 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 the National Park Service and natural resource managers within the parks.

Supplemental_Information:

Raw Lidar data is not in a format that is generally usable by National 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 National 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.

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: Gulf of Mexico

Place_Keyword: Mississippi

Stratum:

Stratum_Keyword: bare earth topography

Access_Constraints:

Any use of these data signifies a user's agreement to comprehension and compliance of the U. S. Geological Survey Standard Disclaimer. Ensure all portions of metadata are read and clearly understood before using these data in order to protect both user and U. S. Geological Survey 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, U. S. Geological Survey does not warrant, endorse, or recommend the use of thes data 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. U. S. Geological Survey is providing these data "as is", and 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 U. S. Geological Survey 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 as a data source would be appreciated in products developed from these data, and such acknowledgement as standad 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 U. S. Geological Survey 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_Person: Dr. John C. Brock

Contact_Position: Physical 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 ext3088

Contact_Facsimile_Telephone: 727 803-2031

Contact_Electronic_Mail_Address: jbrock@usgs.gov

Hours_of_Service: Monday-Friday, 8-5, EST

Browse_Graphic:

Data_Set_Credit:

The U. S. Geological Survey Center for Coastal and Watershed Studies would like to acknowledge NASA Goddard Space Flight Center for their cooperation and assistance in the development of the data. The U. S. Geological Survey would also like to acknowledege 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 ArcCatalog 9.2

Cross_Reference:

Citation_Information:

Originator:

Brock, J.C.; Wright, C.W.; Sallenger, A.H; Krabill, W.B., and Swift, R.N

Publication_Date: 2003

Title:

Basis and Methods of NASA Ariborne Topographic Mapper Lidar Surveys for Coastal Studies

Geospatial_Data_Presentation_Form: journal article

Publication_Information:

Publication_Place: West Palm Beach, Florida

Publisher: Journal of Coastal Research

Cross_Reference:

Citation_Information:

Originator: John Brock and Asbury Sallenger, U. S. Geological Survey, FISC St. Petersburg

Publication_Date: 2001

Title:

Airborne Topographic Lidar Mapping for Coastal Science and Resource Management

Geospatial_Data_Presentation_Form: U. S. Geological Survey Open File Report

Publication_Information:

Publication_Place: St. Petersburg, Florida

Publisher: U. S. Geological Survey

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Data_Quality_Information:

Attribute_Accuracy:

Attribute_Accuracy_Report:

The expected accuracy of the measured variables are 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.

Completeness_Report: unknown

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:

Source_Time_Period_of_Content:

Time_Period_Information:

Single_Date/Time:

Calendar_Date: 20050901, 20050903, 20050904, 20050907, 20050908

Source_Currentness_Reference: ground condition

Process_Step:

Process_Description:

The data are collected using a Cessna 310 aircraft. The NASA Experimental Advanced Airborne Research Lidar (EAARL) laser scanner collects the data using a green (532nm) raster scanning laser, while a digital camera acquires a visual record of the flight. The data are stored on hard drives and archived at the U. S. Geological Survey, FISC St. Petersburg office and the NASA Wallops office. The navigational data are processed at Wallops. The navigational and raw data are then downloaded into the Airborne Lidar Processing System (ALPS). Data are converted from units of time to x,y,z points for elevation. The derived surface data can then be converted into raster data (GeoTIFFs).

Process_Date: 2005

Process_Contact:

Contact_Information:

Contact_Organization_Primary:

Contact_Organization: U. S. Geological Survey, FISC St. Petersburg

Contact_Person: Amar Nayegandhi

Contact_Position: Computer Scientist

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: 8:00am to 5:00pm Monday thru Friday, EST

Contact_Instructions: Call Survey for Details

Process_Step:

Process_Description:

The raster dataset was opened in ERDAS IMAGINE for editing. An Area of Interest (AOI) polygon was drawn around regions of poor data quality. Poor data quality was determined visually by locating gaps in the data as well as artifacts (e.g. spikes, large facets) of the Lidar processing. Pixels within the AOI polygons were given a raster value of -100 to correspond with the classification of 'No Data'

Process_Date: Summer 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, Suite 419

City: Palmetto Bay

State_or_Province: Florida

Postal_Code: 33157

Country: USA

Contact_Voice_Telephone: (305) 252-0347

Process_Step:

Process_Description: Metadata created from XML file.

Process_Date: 20070816

Process_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

Spatial_Data_Organization_Information:

Direct_Spatial_Reference_Method: Raster

Raster_Object_Information:

Raster_Object_Type: Grid Cell

Row_Count: 2000

Column_Count: 2000

Vertical_Count: 1

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:

Entity_and_Attribute_Overview:

The attributes measured are as follows: variables measured by EAARL - distance between aircraft and GPS satellites (m), attitude information (roll, pitch, heading in degrees), scan angle (degrees), second of the epoch (sec), 1-ns time-resolved return intensity waveform (digital counts), and co-registered digital aerial photography. For derived variables, WGS84, NAD83 or other UTM eastings and northings (m), NAVD88 elevations (m), and peak amplitude (intensity). For derived surfaces, bare-earth elevations, and first-surface elevations.

Distribution_Information:

Distributor:

Contact_Information:

Contact_Organization_Primary:

Contact_Organization: U. S. Geological Survey, FISC St. Petersburg

Contact_Address:

Address_Type: mailing 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 Office for Details

Distribution_Liability:

The U. S. Geological Survey shall not be held liable for improper or incorrect use of the data described and/or contained herein. These data and related graphics are not legal documents and are not intended to be used as such.

The information contained in these data is dynamic and may change over time. The data are not better than the original sources from which they were derived. It is the responsibility of the data user to use the data appropriately and consistent within the limitations of geospatial data in general and these data in particular. The related graphics are intended to aid the data user in acquiring relevant data; it is not appropriate to use the related graphics as data.

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 an U. S. Geological Survey 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: 15.275

Ordering_Instructions: Contact U. S. Geological Survey.

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: 20070820

Metadata_Contact:

Contact_Information:

Contact_Organization_Primary:

Contact_Organization: U. S. Geological Survey, FISC. 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