High Accuracy Elevation Data - Lake Okeechobee Littoral Zone

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: Greg Desmond

Publication_Date: 2007

Title: High Accuracy Elevation Data - Lake Okeechobee Littoral Zone

Geospatial_Data_Presentation_Form: text files, shapefile

Publication_Information:

Publication_Place: Reston, VA

Publisher: U.S. Geological Survey

Online_Linkage: <http://sofia.usgs.gov/exchange/desmond/desmondelev.html>

Description:

Abstract:

The U.S. Geological Survey (USGS) coordinated the acquisition of high accuracy elevation data (meters) for the Lake Okeechobee Littoral Zone collected on a 400 meter topographic grid with a vertical accuracy of +/- 15 centimeters. The elevations are referenced to the horizontal North American Datum of 1983 (NAD83) and vertical North American Vertical Datum of 1988 (NAVD88). The topographic surveys were performed using differential GPS technology and a USGS developed helicopter-based instrument known as the Airborne Height Finder (AHF).

The data are available for the areas shown on the USGS High Accuracy Elevation Data graphic at <http://sofia.usgs.gov/exchange/desmond/desmondelev.html>.

Purpose:

This project performed regional topographic surveys to collect and provide elevation data to parameterize hydrologic and ecological numerical simulation models that are being developed for ecosystem restoration activities.

Modeling of sheet flow and water surface levels in the wetlands of South Florida is very sensitive to changes in elevation due to the expansive and extremely low relief terrain. Hydrologists have determined minimum vertical accuracy requirements for the elevation data for use as input to hydrologic models. As a result, elevation data with a vertical accuracy specification of +/-15 centimeters (cm) relative to the North American Vertical Datum of 1988 (NAVD88) are being collected in critical areas using state-of-the-art differential global positioning system (GPS) technology and data processing techniques.

Time_Period_of_Content:

Time_Period_Information:

Range_of_Dates/Times:

Beginning_Date: 20060724

Ending_Date: 20061012

Currentness_Reference: ground condition

Status:

Progress: Complete

Maintenance_and_Update_Frequency: As needed

Spatial_Domain:

Bounding_Coordinates:

West_Bounding_Coordinate: -81.25

East_Bounding_Coordinate: -80.625

North_Bounding_Coordinate: 27.25

South_Bounding_Coordinate: 26.625

Keywords:

Theme:

Theme_Keyword_Thesaurus: none

Theme_Keyword: High accuracy elevation data

Theme_Keyword: mapping

Theme_Keyword: digital elevation data

Theme_Keyword: DEM

Theme_Keyword: elevation

Theme:

Theme_Keyword_Thesaurus: ISO 19115 Topic Category

Theme_Keyword: elevation

Theme_Keyword: 006

Place:

Place_Keyword_Thesaurus:

Department of Commerce, 1995, Countries, Dependencies, Areas of Special Sovereignty, and Their Principal Administrative Divisions, Federal Information Processing Standard (FIPS) 10-4, Washington, DC, National Institute of Standards and Technology

Place_Keyword: United States

Place_Keyword: US

Place:

Place_Keyword_Thesaurus:

U.S. Department of Commerce, 1987, Codes for the identification of the States, the District of Columbia and the outlying areas of the United States, and associated areas (Federal Information Processing Standard 5-2): Washington, DC, NIST

Place_Keyword: Florida

Place_Keyword: FL

Place:

Place_Keyword_Thesaurus:

Department of Commerce, 1990, Counties and Equivalent Entities of the United States, Its Possessions, and Associated Areas, FIPS 6-3, Washington, DC, National Institute of Standards and Technology

Place_Keyword: Okeechobee County

Place_Keyword: Palm Beach County

Place_Keyword: Hendry County

Place_Keyword: Glades County

Place:

Place_Keyword_Thesaurus: USGS Geographic Names Information System

Place_Keyword: Belle Glade

Place_Keyword: Cochrans Pass

Place_Keyword: Fisheating Bay

Place_Keyword: Lakeport

Place_Keyword: Lake Harbor

Place_Keyword: Moore Haven

Place_Keyword: Okeechobee

Place_Keyword: Pahokee

Place_Keyword: Lake Okeechobee

Place:

Place_Keyword_Thesaurus: none

Place_Keyword: Lake Okeechobee Littoral Zone

Place_Keyword: Greater Lake Okeechobee

Place_Keyword: Brighton SE

Place_Keyword: Clewiston North

Place_Keyword: Clewiston South

Place_Keyword: Loxahatchee NW

Place_Keyword: Loxahatchee SE

Place_Keyword: Loxahatchee SW

Access_Constraints: none

Use_Constraints:

None. Acknowledgement of the U.S. Geological Survey would be appreciated for products derived from these data.

Point_of_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Person: Bob Glover

Contact_Organization: U.S. Geological Survey

Contact_Address:

Address_Type: mailing address

Address: 521 National Center

City: Reston

State_or_Province: VA

Postal_Code: 20192

Country: USA

Contact_Voice_Telephone: 703 648-5056

Contact_Electronic_Mail_Address: rglover@usgs.gov

Browse_Graphic:

Browse_Graphic_File_Name: <http://sofia.usgs.gov/exchange/desmond/atlas/>

Browse_Graphic_File_Description:

map of USGS topographic quads containing elevation data around Lake Okeechobee

Browse_Graphic_File_Type: GIF

Browse_Graphic:

Browse_Graphic_File_Name: <http://sofia.usgs.gov/exchange/desmond/desmondelev.html>

Browse_Graphic_File_Description:

map showing the location of high accuracy elevation data around Lake Okeechobee

Browse_Graphic_File_Type: GIF

Data_Set_Credit:

GPS data converted to ESRI shapefile by Susan D. Price. Data collection done by Charles Henkle and Ed Cyran as USGS contractors.

Native_Data_Set_Environment: comma-separated values file and ESRI shapefile

Data_Quality_Information:

Logical_Consistency_Report: not available

Completeness_Report:

All verified and accepted data points are included in the files for each area

Positional_Accuracy:

Horizontal_Positional_Accuracy:

Horizontal_Positional_Accuracy_Report:

Horizontal positions are established by GPS observations and are referenced to the North American Datum of 1983 (NAD83). The desired horizontal accuracy is +/- 15 centimeters. This level of accuracy is consistent with GPS differential techniques which use two stations - a high-quality dual-frequency GPS receiver base station and a roving GPS station. The density and accuracy of a given GPS data observation varies from a few meters to a few centimeters according to the Position Dilution of Precision (PDOP) in the study area. Generally if the PDOP is observed to be excessive, data collection is discontinued or the data are discarded. The PDOP is an indicator of the positional accuracy of the GPS that be can derived from the current GPS satellite geometry, which varies continuously. Generally the smaller the PDOP number, the higher the data quality. The PDOP is a permanent part of the recorded data and is also included in the post processing procedures during reduction of the GPS observations to NAD 83. Where possible, the GPS base station has an ellipsoid height to an accuracy of two centimeters relative to the Continuously Operating Reference Stations (CORS) or the High Accuracy Reference Network (HARN), both operated by the National Geodetic Survey (NGS).

Vertical_Positional_Accuracy:

Vertical_Positional_Accuracy_Report:

For all elevation data the vertical accuracy specification is +/- 15 centimeters and is referenced to NAVD 1988.

This elevation data is intended primarily for use in hydrological modeling. It is collected as high accuracy, "bare earth" ground elevation. That is, the data are restricted to ground elevations only. "Bare earth" in the Everglades swamp environment is generally considered to be the layer of "muck" which will support a one pound weight on a bearing surface of approximately 5.3 square inches (2.6 inch circle). In non-swamp areas it is actual bare ground.

Lineage:

Process_Step:

Process_Description:

The process consists of the following steps:

1.Collection of GPS XYZ points and vegetation classification in the Lake Okeechobee Littoral Zone using the helicopter-based Airborne Height Finder (AHF) developed by the USGS.

2. The GPS data were processed into an ASCII list of NAD83 geographic XY coordinates, NAVD88 elevation Z value and descriptor attribute data. This file was transformed using Corpscon, version 5.11.08 from the U.S. Army Corps of Engineers to NAD83 UTM XY and NAVD88 Z coordinates. The file was output as an ASCII text file and processed at USGS in Reston, VA.

3. The x,y, and z values of the ASCII text file were reformatted to the decimal value of 100th of meter (centimeter) to represent the accuracy of the data and then imported into ArcGIS 9.1 to create an ESRI shapefile.

4. The ESRI shapefile was compressed into a .zip file using WinZip. The associated .dbf files were opened in MS Excel and saved as the comma separated value file which also is available for download.

Process_Date: 200708

Process_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Person: Susan D. Price

Contact_Organization: U.S. Geological Survey

Contact_Address:

Address_Type: mailing address

Address: 521 National Center

City: Reston

State_or_Province: VA

Postal_Code: 20192

Country: USA

Contact_Voice_Telephone: 703 648 6692

Contact_Electronic_Mail_Address: sprice@usgs.gov

Spatial_Data_Organization_Information:

Indirect_Spatial_Reference: South Florida - Lake Okeechobee Littoral Zone

Direct_Spatial_Reference_Method: Vector

Point_and_Vector_Object_Information:

SDTS_Terms_Description:

SDTS_Point_and_Vector_Object_Type: Entity point

Point_and_Vector_Object_Count: 2865

Spatial_Reference_Information:

Horizontal_Coordinate_System_Definition:

Planar:

Grid_Coordinate_System:

Grid_Coordinate_System_Name: Universal Transverse Mercator

Universal_Transverse_Mercator:

UTM_Zone_Number: 17

Transverse_Mercator:

Scale_Factor_at_Central_Meridian: 0.9996

Longitude_of_Central_Meridian: -81

Latitude_of_Projection_Origin: 0

False_Easting: 500000

False_Northing: 0

Planar_Coordinate_Information:

Planar_Coordinate_Encoding_Method: Coordinate Pair

Coordinate_Representation:

Abscissa_Resolution: 400

Ordinate_Resolution: 400

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: 298.257

Vertical_Coordinate_System_Definition:

Altitude_System_Definition:

Altitude_Datum_Name: North American Vertical Datum of 1988

Altitude_Resolution: .01

Altitude_Distance_Units: meters

Altitude_Encoding_Method:

Explicit elevation coordinate included with horizontal coordinates

Entity_and_Attribute_Information:

Detailed_Description:

Entity_Type:

Entity_Type_Label: ELEV_M

Entity_Type_Definition: ground surface elevation in meters

Entity_Type_Definition_Source: USGS

Detailed_Description:

Entity_Type:

Entity_Type_Label: X_UTM

Entity_Type_Definition: UTM X coordinate in meters for the data collection point

Entity_Type_Definition_Source: USGS

Detailed_Description:

Entity_Type:

Entity_Type_Label: Y_UTM

Entity_Type_Definition: UTM Y coordinate in meters for the data collection point

Entity_Type_Definition_Source: USGS

Detailed_Description:

Entity_Type:

Entity_Type_Label: QUAD_NAME

Entity_Type_Definition:

The name of the USGS 1:24,000-scale topographic quadrangle in which the point falls

Entity_Type_Definition_Source: USGS

Detailed_Description:

Entity_Type:

Entity_Type_Label: VEG_FS

Entity_Type_Definition:

The vegetation observed by the surveyor at the data collection point. Vegetation types include Alligator Hole, Broadleaf Emergent, Cattail, Cypress, Floating Emergent, Hardwood, Lygodium, Melaleuca, Open Water, Palmetto, Pine, Sawgrass, Shrub, Slough, Tree Island, Wet Prairie, Wet Prairie/Slough, and Willow Shrub

Entity_Type_Definition_Source: USGS

Detailed_Description:

Entity_Type:

Entity_Type_Label: SUR_METHOD

Entity_Type_Definition:

type of surveying method - all data for the Lake Littoral zone were collected using the helicopter based Airborne Height Finder (AHF)

Entity_Type_Definition_Source: USGS

Detailed_Description:

Entity_Type:

Entity_Type_Label: SUR_INFO

Entity_Type_Definition:

Characters 1-5 are the file name used by the surveyor during data collection. Characters 6-8 are the Julian date of the data collection. Characters 9-10 are the year the data were collected. Character 11 is a blank space. Characters 12-19 represent the date the data were released for publication and archive after the data have been collected, processed, edited, quality controlled, and approved for release. Character 20 is "Y" which means the data can be released. This is not the date the data were collected.

If new data were added to the quadrangle, the revision date was modified for ALL points in the quadrangle to reflect the latest revision date. At the completion of data collection, the individual quad-based files were aggregated to create the larger files now available for download.

Entity_Type_Definition_Source: USGS

Detailed_Description:

Entity_Type:

Entity_Type_Label: SUR_FILE

Entity_Type_Definition:

file name used by the surveyor for internal data management purposes

Entity_Type_Definition_Source: USGS

Distribution_Information:

Distributor:

Contact_Information:

Contact_Person_Primary:

Contact_Person: Heather S.Henkel

Contact_Organization: U.S. Geological Survey

Contact_Address:

Address_Type: mailing address

Address: 600 Fourth St. South

City: St. Petersburg

State_or_Province: FL

Postal_Code: 33701

Country: USA

Contact_Voice_Telephone: 727 803-8747 ext 3028

Contact_Facsimile_Telephone: 727 803-2030

Contact_Electronic_Mail_Address: hhenkel@usgs.gov

Resource_Description: Helicopter - Airborne Height Finder

Distribution_Liability: No warrantees are implied or explicit for the data

Standard_Order_Process:

Digital_Form:

Digital_Transfer_Information:

Format_Name: ASCII

Format_Version_Date: 1985

Format_Specification: .csv

Format_Information_Content:

comma separated values file of Global Positioning System (GPS) points

Transfer_Size: 0.261

Digital_Transfer_Option:

Online_Option:

Computer_Contact_Information:

Network_Address:

Network_Resource_Name: <http://sofia.usgs.gov/exchange/desmond/desmondelev.html>

Access_Instructions: File may be downloaded from the SOFIA website

Digital_Form:

Digital_Transfer_Information:

Format_Name: zip

Format_Version_Number: unknown

Format_Specification: shp.zip

Format_Information_Content: ArcGIS shapefile and associated files

File_Decompression_Technique: the file must be unzipped before use

Transfer_Size: 0.109

Digital_Transfer_Option:

Online_Option:

Computer_Contact_Information:

Network_Address:

Network_Resource_Name: <http://sofia.usgs.gov/exchange/desmond/desmondelev.html>

Access_Instructions: File may be downloaded from the SOFIA website

Fees: none

Metadata_Reference_Information:

Metadata_Date: 20071024

Metadata_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Person: Heather Henkel

Contact_Organization: U.S. Geological Survey

Contact_Address:

Address_Type: mailing and physical address

Address: 600 Fourth Street South

City: St. Petersburg

State_or_Province: FL

Postal_Code: 33701

Country: USA

Contact_Voice_Telephone: 727 803-8747 ext 3028

Contact_Facsimile_Telephone: 727 803-2030

Contact_Electronic_Mail_Address: sofia-metadata@usgs.gov

Metadata_Standard_Name: Content Standard for Digital Geospatial Metadata

Metadata_Standard_Version: FGDC-STD-001-1998

U.S. Department of the Interior, U.S. Geological Survey
Comments and suggestions? Contact: Heather Henkel - Webmaster
Generated by mp version 2.8.18 on Wed Oct 24 14:49:41 2007