Astronomical High Tide Line for Louisiana, Geographic NAD83, NWRC (1999) [hightide]

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: USGS National Wetlands Research Center

Publication_Date: 19950101

Title:

Astronomical High Tide Line for Louisiana, Geographic NAD83, NWRC (1999) [hightide]

Geospatial_Data_Presentation_Form: Map

Description:

Abstract:

The astronomical high tide line was compiled from National Wetlands Inventory (NWI) 1:24,000-scale habitat maps that were photo-interpreted from color-infrared aerial photography acquired between November 1988 and March 1989 at a scale of 1:65,000. Inland extent of tidal influence was then determined from the 1988 Chabreck and Linscombe marsh vegetation maps, photo-interpretation, field review, and information gathered from discussions with regional and local experts. Only semi-diurnal and diurnal gravity tides are considered in the NWI classification because of the general lack of information on wind-influenced tidal fluctuations and ranges. All saltwater wetlands (saline, brackish, and intermediate) in coastal Louisiana were considered to be tidal unless impounded, and tidally influenced freshwater wetlands were included in the tidal zone as well. In general, the division between salt water and fresh water is considered to be the limit of gravitation tidal influence for coastal Louisiana.

Arcs that close delineate isolated areas above the astronomical high tide line, but are not built into topological polygons.

Purpose:

The purpose is to provide the Astronomical High Tide Line for Louisiana Oil Spill Contingency Plan Map. The Louisiana Oil Spill Contingency Plan Map was published to fulfill the requirements of the Oil Spill Prevention and Response Act under the authority of R.S. 30:2459(D)

Time_Period_of_Content:

Time_Period_Information:

Single_Date/Time:

Calendar_Date: 19950101

Currentness_Reference: Ground Condition during source photography acquisition.

Status:

Progress: Complete

Maintenance_and_Update_Frequency: None Planned

Spatial_Domain:

Bounding_Coordinates:

West_Bounding_Coordinate: -90.00

East_Bounding_Coordinate: -89.00

North_Bounding_Coordinate: 29.500

South_Bounding_Coordinate: 28.875

Keywords:

Theme:

Theme_Keyword_Thesaurus: None

Theme_Keyword: tides

Theme_Keyword: NASA aerial photography

Theme_Keyword: aerial photography

Theme_Keyword: tide line

Theme_Keyword: coast

Theme_Keyword: coastal

Theme_Keyword: geographic information system data

Theme_Keyword: classified aerial photography

Theme_Keyword: maps

Theme_Keyword: mapping

Place:

Place_Keyword_Thesaurus: None

Place_Keyword: Louisiana

Place_Keyword: Louisiana Coast

Place_Keyword: Gulf of Mexico

Place_Keyword: South Louisiana

Place_Keyword: Mississippi River

Access_Constraints:

Any use of these data signifies a user's agreement to comprehension and compliance of the NWRC Standard Disclaimer. Insure all portions of metadata are read and clearly understood before using these data in order to protect both user and NWRC interests.

Use_Constraints:

Acknowledgement of the National Wetlands Research 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 for data source is expected by users of this data. Sharing new data layers developed directly from these data would also be appreciated by NWRC staff. Users should be aware that comparison with other data sets for the same area from other time periods may be inaccurate due to inconsistencies resulting from changes in photo-interpretation and mapping conventions over time. These data are not legal documents and are not to be used as such. Persons intending to engage in activities involving modifications within or adjacent to wetland areas should seek the advice of appropriate Federal, State, or local agencies concerning specified agency regulatory programs and proprietary jurisdictions that may affect such activities.

Point_of_Contact:

Contact_Information:

Contact_Organization_Primary:

Contact_Organization: USGS National Wetlands Research Center

Contact_Person: Larry Handley

Contact_Position: Geographer and Principle Investigator

Contact_Address:

Address_Type: Mailing and Physical Address

Address: 700 Cajundome Blvd

City: Lafayette

State_or_Province: LA

Postal_Code: 70506

Contact_Voice_Telephone: 318 266-8691

Contact_Facsimile_Telephone: 318 266-8513

Contact_Electronic_Mail_Address: larry_handley@usgs.gov

Browse_Graphic:

Browse_Graphic_File_Name: <URL:hightide1.gif>

Browse_Graphic_File_Description: thumbnail view of data set

Browse_Graphic_File_Type: GIF

Data_Quality_Information:

Attribute_Accuracy:

Attribute_Accuracy_Report:

The attribute accuracy was tested using several methods during the data development phases and completion. Data was tested by manual comparison of the source with hard copy printouts and/or symbolized display of the digital wetlands data on an interactive computer graphic system. In addition, WAMS software tests the attributes. Overall, the attribute accuracy is believed high due to the multiple error-checking steps done redundantly during processing. Process testing was done on the multiple staff error-checking steps and software error-checking steps to develop estimates of the accuracy and error rates. The final accuracy assessment used calculated average accuracy and error rates for the human stages and software verification stages, which were done redundantly to insure double checking verification of the data coverages comprising the data set. Exact tolerances vary with coverages, as does the date of the processing and testing. The final accuracy values expressed are the best summation, which can be developed from the smaller areas, which comprise the data set. Data has been checked and verified against original maps and over years of use. The accuracy values expressed represent the final calculated accuracy estimate of the multiple steps of data development from source photography to completed data. The actual final should be considered as average and perhaps conservative or over estimating the percent change of error for areas in this data set.

Logical_Consistency_Report:

This logical consistency report includes information about both general and specific topological tests and data generation dynamics in the fidelity of data. Data is inherently linear. Line segments are a set of sequentially numbered coordinate pairs. No duplicate features exist nor duplicate points in a data string. Intersecting lines are separated into individual line segments at the points of intersection. All nodes are represented by a single coordinate pair which indicates the beginning or end of a line segment. The neatline for each quad is generated by connecting four corners of a digital file, as established during initialization of the digital file. All data crossing the neatline are clipped to the neatline and data within a specified tolerance of the neatline are snapped to the neatline. The High Tide Line was produced as a dividing line between wetlands and deep water habitats as classified in: Cowardin, Lewis M., Virginia Carter, Francis Goblet, and Edward T. Laroe. Classification of wetlands and deepwater habitats of the United States. U.S. Fish and Wildlife Service. Biological Services Program; FWS/OBS - 79/31. It was digitized by line scan digitizing, and then attributed.

Completeness_Report:

All photo-interpretable wetlands are identified and mapped using standard methodologies and equipment for the photo interpretation phases of the data development. Processing of the digital data also follows conventions and standard methodologies for the time period and within limitations of available workstation equipment at the date of data development. Cartographic transformation of the tide line was completed across the entire coast from the Sabine River to Chandeleur Sound. In general, the division between salt water and fresh water is considered to be the limit of gravitation tidal influence for coastal Louisiana. All saltwater wetlands (saline, brackish, and intermediate) in coastal Louisiana were considered to be tidal unless impounded, and tidally influenced freshwater wetlands were included in the tidal zone as well. Daily water-levels fluctuations are common in many freshwater wetland areas within the northern limit of the Louisiana coastal wetlands. These freshwater wetlands were not included in the tidal zone, unless information was available about diurnal fluctuations or from expert advise. Some well-known, isolated, impounded areas within the tidal zone are excluded because they usually are unaffected by daily tidal action. Many other impoundments were not excluded from the tidal zone because, according to experts, either they were affected by normal tidal action or there is not enough information available to determine the extent of tidal influence. Known impoundments, areas within flood control levees, and upland areas were not included within the tidal zone. The tide line and excluded areas were delineated on USGS 1:24,000-scale maps and then transferred to a USGS 1:100,000-scale map. Linework on the 1:100,000-scale maps was scanned and digitized with line-following software. Processing follows standard operating procedures as used, developed, and shared by the National Wetlands Inventory of the U.S. Fish and Wildlife Service. Data products were completed using similar systems and methodologies, which are used by NWI and by USGS.

Positional_Accuracy:

Horizontal_Positional_Accuracy:

Horizontal_Positional_Accuracy_Report:

For reference points accuracy, the accuracy for the digital data are tested by visual comparison of the source with hard copy maps, and by understanding of the hardware tolerances and processing values reported by the software used in data development. Additional checks on comparison were possible when georeferencing/rectification was done using the USGS maps, which cite National Mapping Accuracy Standard compliance.

Lineage:

Source_Information:

Source_Citation:

Citation_Information:

Originator: National Aeronautics and Space Administration

Publication_Date: 19880101

Title: Color Infrared Aerial Photography

Edition: Varies

Geospatial_Data_Presentation_Form: Remote-Sensing Image

Publication_Information:

Publication_Place: NASA Ames,California

Publisher:

National Aeronautics and Space Administration (NASA), United States

Source_Scale_Denominator: 65000

Type_of_Source_Media: Stable-Base Material

Source_Time_Period_of_Content:

Time_Period_Information:

Single_Date/Time:

Calendar_Date: 19880101

Source_Currentness_Reference: Source Photography Date

Source_Citation_Abbreviation: NASA CIR

Source_Contribution:

Primary data for photo interpretation and identification of wetland and upland classes.

Source_Information:

Source_Citation:

Citation_Information:

Originator: United States Geological Survey (USGS)

Publication_Date: 1953-1983

Title: USGS Topographic Quadrangles, standard 7.5 minute series maps

Edition: Varies

Geospatial_Data_Presentation_Form: Map

Publication_Information:

Publication_Place: Reston, VA

Publisher: United States Geological Survey (USGS)

Source_Scale_Denominator: 24000

Type_of_Source_Media: Paper

Source_Time_Period_of_Content:

Time_Period_Information:

Single_Date/Time:

Calendar_Date: 1953-1983

Source_Currentness_Reference: Source map date

Source_Citation_Abbreviation: USGS Quads

Source_Contribution:

Provided base maps for wetland and upland polygon layer information.

Source_Information:

Source_Citation:

Citation_Information:

Originator:

United States Fish and Wildlife Service's National Wetlands Inventory

Publication_Date: 19880101

Title: National Wetlands Inventory Hard Copy Wetland Maps

Geospatial_Data_Presentation_Form: Map

Publication_Information:

Publication_Place: St. Petersburg, Fl

Publisher: U.S. Fish and Wildlife Service's National Wetlands Inventory

Source_Scale_Denominator: 24000

Type_of_Source_Media: Hard copy maps

Source_Time_Period_of_Content:

Time_Period_Information:

Single_Date/Time:

Calendar_Date: 19880101

Source_Currentness_Reference: Source photography for maps

Source_Citation_Abbreviation: NWI Maps

Source_Contribution: Provided hard copy maps to be digitized.

Process_Step:

Process_Description:

NASA High altitude 1:65,000 color infrared aerial photographs were photo interpreted for wetland and upland habitat classifications. Habitat layer was overlaid on USGS Quad base maps to create the NWI maps

Process_Date: 1989-1992

Process_Step:

Process_Description:

The hard copy 1:24,000 NWI maps were digitized at the National Wetlands Research Center using WAMS (Wetland Analytical Mapping System).

Process_Date: 1993

Process_Step:

Process_Description:

Dataset projected to geographic coordinates, NAD83 by LSU Department of Geography and Anthropology

Process_Date: 1999

Spatial_Data_Organization_Information:

Direct_Spatial_Reference_Method: Vector

Spatial_Reference_Information:

Horizontal_Coordinate_System_Definition:

Geographic:

Latitude_Resolution: 0.000005

Longitude_Resolution: 0.000005

Geographic_Coordinate_Units: Decimal degrees

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

Entity_and_Attribute_Information:

Detailed_Description:

Entity_Type:

Entity_Type_Label: hightide.dbf

Entity_Type_Definition: attributes of hightide arcs

Entity_Type_Definition_Source: 3001, Inc.

Attribute:

Attribute_Label: length_m

Attribute_Definition: length of hightide arc segment

Attribute_Definition_Source: LSU Department of Geography and Anthropology

Attribute_Domain_Values:

Range_Domain:

Range_Domain_Minimum: 8.577

Range_Domain_Maximum: 8261.084

Attribute_Units_of_Measure: meters

Distribution_Information:

Distributor:

Contact_Information:

Contact_Organization_Primary:

Contact_Organization: USGS National Wetlands Research Center

Contact_Person: Larry Handley

Contact_Position: Geographer and Principle Investigator

Contact_Address:

Address_Type: Mailing and Physical Address

Address: 700 Cajundome Blvd.

City: Lafayette

State_or_Province: Louisiana

Postal_Code: 70506

Country: USA

Contact_Voice_Telephone: 318 266-8691

Contact_Facsimile_Telephone: 318 266-8513

Contact_Electronic_Mail_Address: larry_handley@usgs.gov

Hours_of_Service: 8:00 a.m. to 4:00 p.m. Monday Through Friday

Distribution_Liability:

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 accuracy 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. This disclaimer applies both to individual use of the data and aggregate use with other data. It is strongly recommended that these data are directly acquired from a U.S. Geological Survey server, and not indirectly through other sources which may have changed the data in some way. It is also strongly recommended that careful attention be paid to the contents of the metadata file associated with these data. The U.S. Geological Survey shall not be held liable for improper or incorrect use of the data described and/or contained herein.

Metadata_Reference_Information:

Metadata_Date: 19991210

Metadata_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Person: Suzanne Harrison

Contact_Organization: University of Southwestern Louisiana

Contact_Position: GIS Specialist

Contact_Address:

Address_Type: Mailing and Physical Address

Address: 700 Cajundome Blvd

City: Lafayette

State_or_Province: Louisiana

Postal_Code: 70506

Country: USA

Contact_Voice_Telephone: 318 266-8698

Contact_Facsimile_Telephone: 318 266-8513

Contact_Electronic_Mail_Address: suzanne_harrison@usgs.gov

Hours_of_Service:

8:00 a.m. to 4:00 p.m. CST for phone calls. Any hours for E-mail or fax transmit.

Metadata_Standard_Name:

Draft Content Standard for National Biological Information Infrastructure Metadata, National Biological Service

Metadata_Standard_Version: FGDC-STD-001-1998

Metadata_Access_Constraints: See Access_Constraints

Metadata_Use_Constraints: None