High Accuracy Elevation Data - Water Conservation Areas and Greater Everglades Region

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: 200710

Title:

High Accuracy Elevation Data - Water Conservation Areas and Greater Everglades Region

Geospatial_Data_Presentation_Form: text files, shapefiles

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

Description:

Abstract:

The High Accuracy Elevation Data Project collected elevation data (meters) on a 400 meter topographic grid with a vertical accuracy of +/- 15 centimeters to define the topography in South Florida. The data are referenced to the horizontal datum North American Datum 1983 (NAD 83) and the vertical datum North American Vertical Datum 1988 (NAVD 88). In some areas, the surveying was accomplished using airboats. Because access was a logistical problem with airboats, the USGS developed a helicopter-based instrument known as the Airborne Height Finder (AHF). All subsequent data collection used the AHF. Data were collected from the Loxahatchee National Wildlife Refuge, south through the Water Conservation Areas (1A, 2A, 2B, 3A, and 3B), Big Cypress National Park, the Everglades National Park, to the Florida Bay. 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>. The work was performed for Everglades ecosystem restoration purposes.

Purpose:

The data are from 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. Surveying services were also rendered to provide vertical reference points for numerous water level gauges.

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 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) were 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: 1995

Ending_Date: 2007

Currentness_Reference: ground condition

Status:

Progress: Complete

Maintenance_and_Update_Frequency: As needed

Spatial_Domain:

Bounding_Coordinates:

West_Bounding_Coordinate: -81.5

East_Bounding_Coordinate: -80.125

North_Bounding_Coordinate: 26.75

South_Bounding_Coordinate: 25.125

Keywords:

Theme:

Theme_Keyword_Thesaurus: none

Theme_Keyword: High accuracy elevation data

Theme_Keyword: mapping

Theme_Keyword: digital elevation data

Theme_Keyword: DEM

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: Broward County

Place_Keyword: Collier County

Place_Keyword: Miami-Dade County

Place_Keyword: Monroe County

Place:

Place_Keyword_Thesaurus: none

Place_Keyword: South East Coast

Place_Keyword: SW Big Cypress

Place_Keyword: Cooper City SW

Place_Keyword: Coral Springs NE

Place_Keyword: East of Deem City

Place_Keyword: East of Lone Palm Head

Place_Keyword: Hialeah SW

Place_Keyword: Lake Ingraham East

Place_Keyword: Lake Ingraham West

Place_Keyword: Loxahatchee NW

Place_Keyword: Loxahatchee SE

Place_Keyword: Loxahatchee SW

Place_Keyword: North of Fortymile Bend

Place_Keyword: Royal Palm Ranger Station SE

Place_Keyword: South of Coopertown

Place_Keyword: South of Deem City

Place_Keyword: West of Big Lake

Place_Keyword: West of Deem City

Place_Keyword: West of Pennsuco

Place_Keyword: Whitewater Bay East

Place_Keyword: Whitewater Bay West

Place_Keyword: Cooper City NE

Place_Keyword: Monroe Station NE

Place_Keyword: North of Deem City

Place_Keyword: North of Fiftymile Bend

Place_Keyword: North of Lone Palm Head

Place_Keyword: South Miami NW

Place_Keyword: West of Horseshoe Head

Place_Keyword: Central Everglades

Place:

Place_Keyword_Thesaurus: USGS Geographic Names Information System

Place_Keyword: Andytown

Place_Keyword: Big Boy Lake

Place_Keyword: Big Lostmans Bay

Place_Keyword: Black Hammock

Place_Keyword: Blackwater Sound

Place_Keyword: Chekika Island

Place_Keyword: Chokoloskee

Place_Keyword: Coopertown

Place_Keyword: Custard Apple Hammock

Place_Keyword: Fiftymile Bend

Place_Keyword: Flamingo

Place_Keyword: Fortymile Bend

Place_Keyword: Gator Hook Swamp

Place_Keyword: Glades

Place_Keyword: Grossman Hammock

Place_Keyword: Harney River

Place_Keyword: Homestead

Place_Keyword: Horseshoe Head

Place_Keyword: Indian Camp Creek

Place_Keyword: Joe Bay

Place_Keyword: Long Island

Place_Keyword: Long Pine Key

Place_Keyword: Lostmans River Ranger Station

Place_Keyword: Lostmans Trail

Place_Keyword: Madeira Bay

Place_Keyword: Mahogany Hammock

Place_Keyword: Melaleuka Head

Place_Keyword: Monroe Station

Place_Keyword: Ochopee

Place_Keyword: Pa-Hay-Okee Lookout Tower

Place_Keyword: Panther Mound

Place_Keyword: Pavillion Key

Place_Keyword: Pennsuco

Place_Keyword: Royal Palm Ranger Station

Place_Keyword: Shark Point

Place_Keyword: Tarpon Bay

Place_Keyword: Taylor Slough

Place_Keyword: West Lake

Place_Keyword: Shark River Island

Place_Keyword: Shark Valley Lookout Tower

Place_Keyword: Big Lake

Place_Keyword: Gator Lake

Place_Keyword: Greenacres City

Place_Keyword: Lone Palm Head

Place_Keyword: Loxahatchee

Place_Keyword: University Park

Place_Keyword: California Slough

Place_Keyword: Deem City

Place_Keyword: Everglades City

Place_Keyword: Plover Key

Place_Keyword: Sandy Key

Place_Keyword: Weavers Station

Place_Keyword: West Dixie Bend

Place_Keyword: Alligator Bay

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/desmondelev.html>

Browse_Graphic_File_Description:

map showing water conservation areas and greater Everglades region

Browse_Graphic_File_Type: GIF

Browse_Graphic:

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

Browse_Graphic_File_Description:

map showing topographic quadrangles in the water conservation areas and greater Everglades region

Browse_Graphic_File_Type: GIF

Data_Set_Credit:

Data collection done by Charles Henkle, Gordon Shupe, Bob Glover, Ed Cyran, and Greg Desmond of the USGS and contractors. Other project personnel include Vince Caruso, Gary Freeman, and Susan Price.

Native_Data_Set_Environment:

compressed ArcGIS shapefile (.zip), comma-separated value file (.csv), and compressed .csv (.zip)

Data_Quality_Information:

Logical_Consistency_Report:

The Grossman Hammock and Perrine quadrangles have helicopter AHF & airboat and truck data

Completeness_Report:

All verified and accepted data points are included in the files for the 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 for creating digital elevation files consisted of the following steps:

1. Collection of GPS XYZ points in and around the Greater Everglades Region from the Water Conservation Areas (1A, 2A, 2B, 3A, and 3B), Big Cypress National Preserve, the Everglades National Park, to the Florida Bay, and environs using the following collection platforms: airboat and helicopter-based Airborne Height Finder (AHF) developed by the USGS.

2. The GPS data were transformed from NAD83 geographic X, Y coordinates and NAVD88 elevation Z valuse to NAD83 UTM X, Y and NAVD88 Z coordinates via "Corpscon for Windows" from the U.S. Army Corps of Engineers. <http://crunch.tec.army.mil/software/corpscon/corpscon.html>

3. The coordinate data were imported into a geographic information system to create multiple geospatial data formats.

4. Multiple formats of the data were posted to the SOFIA website.

5. This process was repeated for each quad-based file of data collected by the surveyors during the 12 year life of the project.

6. The ASCII text files containing more than 50,000 data records were aggregated and reformatted using custom shell scripts. These data were imported into ArcGIS (version 9.1) to create the the shapefile HAED_v01.shp available for download.

7. The associated .dbf files were opened in MS Excel and saved as the comma-separated values files which also are 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: Water Conservation areas and greater Everglades region

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: 57395

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: X UTM 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: Y UTM 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 1:20,000-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

Entity_Type_Definition_Source: USGS

Attribute:

Attribute_Label: AHF

Attribute_Definition:

Airborne Height Finder - a helicopter-based instrument used to access data points

Attribute_Definition_Source: USGS

Attribute_Domain_Values:

Unrepresentable_Domain: AHF

Attribute:

Attribute_Label: airboat

Attribute_Definition: data collected using an airboat to access data points

Attribute_Definition_Source: USGS

Attribute_Domain_Values:

Unrepresentable_Domain: airboat

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.

During the 12 year lifetime of the project, data points were released as individual files (see SUR_FILE attribute) to match the published USGS 7.5-minute topographic quadrangle footprint. 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 & airboat

Distribution_Liability: No warrantees are implied or explicit for the data

Standard_Order_Process:

Digital_Form:

Digital_Transfer_Information:

Format_Name: ASCII

Format_Version_Number: 1985

Format_Specification: csv

Format_Information_Content: comma-separated values for the elevations in map area 2

Transfer_Size: 4.5

Digital_Transfer_Option:

Online_Option:

Computer_Contact_Information:

Network_Address:

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

Access_Instructions: File amy be downloaded form the SOFIA website

Digital_Form:

Digital_Transfer_Information:

Format_Name: zip

Format_Version_Number: unknown

Format_Specification: csv.zip

Format_Information_Content: comma-separated values for elevations in map area 2

File_Decompression_Technique: file must be unzipped before use

Transfer_Size: 0.7

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 shapefiles and associated files for map area 2

File_Decompression_Technique: file must be unzipped before use

Transfer_Size: 1.7

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 15:00:34 2007