Aerial Survey Maps from Brown Marsh Survey of Coastal Louisiana

Frequently-anticipated questions:


What does this data set describe?

    Title: Aerial Survey Maps from Brown Marsh Survey of Coastal Louisiana
    Abstract:
    This data set consists of maps depicting the monthly aerial surveys conducted by the National Wetlands Research Center. The surveys were done, using a USGS/NWRC fix-winged amphibious aircraft, in Southeast Louisiana in June, August, September, October and November 2000 and January and February 2001. Each transect was visited on each flight over. A general color (Brown, Brown-Green, Green-Brown, Green) was assigned to the area of marsh directly beneath the wing at 5 second intervals. As color was assigned, the health designation and latitude and longitude of the area was recorded into Voice/GPS Survey, a voice transcription software created by the U.S. Fish and Wildlife Service, on a laptop with a link to a Trimble 2000 GPS unit.

  1. How should this data set be cited?

    U.S Geological Survey, Biological Resources Division's National W, 2003, Aerial Survey Maps from Brown Marsh Survey of Coastal Louisiana:.

    This is part of the following larger work.

    Barataria-Terrebonne National Estuary Program Scientific-Technical Committee, 20010207, Requests for submission of Scope of Services for Marsh Dieback and Nutria Control Emergency Response.: Barataria-Terrebonne National Estuary Program Scientific-Technical Committee, Thibodaux, LA.

    Online Links:

  2. What geographic area does the data set cover?

    West_Bounding_Coordinate: -93.899
    East_Bounding_Coordinate: -89.524
    North_Bounding_Coordinate: 29.917
    South_Bounding_Coordinate: 29.212
    Description_of_Geographic_Extent: Coastal Louisiana

  3. What does it look like?

  4. Does the data set describe conditions during a particular time period?

    Beginning_Date: Jun-2000
    Ending_Date: Aug-2002
    Currentness_Reference: Ground condition

  5. What is the general form of this data set?

    Geospatial_Data_Presentation_Form: Raster Digital database

  6. How does the data set represent geographic features?

    1. How are geographic features stored in the data set?

      This is a Raster data set.

    2. What coordinate system is used to represent geographic features?

      Grid_Coordinate_System_Name: Universal Transverse Mercator
      Universal_Transverse_Mercator:
      UTM_Zone_Number: 15
      Transverse_Mercator:
      Longitude_of_Central_Meridian: -93
      Latitude_of_Projection_Origin: 0
      False_Easting: 500,000
      False_Northing: 0
      Scale_Factor_at_Central_Meridian: .9996

      Planar coordinates are encoded using Coordinate Pair
      Abscissae (x-coordinates) are specified to the nearest .61
      Ordinates (y-coordinates) are specified to the nearest .61
      Planar coordinates are specified in Meters

      The horizontal datum used is North American Datum of 1983.
      The ellipsoid used is GRS 1980.
      The semi-major axis of the ellipsoid used is 6378137.0.
      The flattening of the ellipsoid used is 1/298.257.

  7. How does the data set describe geographic features?

    Aerial Survey
    Data taken from aerial survey of the coastal marsh die-back. (Source: Project defined)

    Data
    Attribute information (Source: Project defined)

    ValueDefinition
    BrownThe percentage of marsh color to determine health designation
    Brown-GreenThe percentage of marsh color to determine health designation
    Green-BrownThe percentage of marsh color to determine health designation
    GreenThe percentage of marsh color to determine health designation


Who produced the data set?

  1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)

  2. Who also contributed to the data set?

  3. To whom should users address questions about the data?

    U.S. Geological Survey, Biological Resource Division's, National Wetlands Research Center
    c/o Tommy Michot
    Wildlife Biologist
    700 Cajundome Blvd
    Lafayette, Louisiana 70506

    337-266-8664 (voice)
    337-266-8592 (FAX)
    tommy_michot@usgs.gov


Why was the data set created?

To determine the extent of the Brown Marsh phenomenon of Coastal Louisiana


How was the data set created?

  1. From what previous works were the data drawn?

    GPS (source 1 of 3)
    U.S. Geological Survey, National Wetlands Research Center, 2000, GPS coordinates with marsh values: USGS National Wetlands Research Center, Lafayette, LA.

    Type_of_Source_Media: digital database file
    Source_Contribution: Primary source of locations along the flight line transects

    LOSCO TM (source 2 of 3)
    Louisiana Oil Spill Coordinator's Office (LOSCO), 1999, Thematic Mapper Image of Louisiana, UTM15 NAD83, LOSCO: Louisiana State University, Baton Rouge, LA.

    Type_of_Source_Media: Raster digital database
    Source_Contribution: Secondary source for maps, base maps.

    LOSCO Parish (source 3 of 3)
    Louisiana Oil Spill Coordinator's Office (LOSCO), 1999, Parish Boundaries of Louisiana from LDOTD source data: Louisiana State University, Baton Rouge, LA.

    Type_of_Source_Media: Digital database file
    Source_Contribution: Secondary data source for aerial survey maps

  2. How were the data generated, processed, and modified?

    Date: 2000 (process 1 of 1)
    GPS coordinates and data collected through aerial surveys were placed into a GIS database. These points were layered on secondary data sources (parishes boundaries and TM imagery) and color coded to indicate marsh health. This information was then placed into a standard map layout, using ArcView. A map was generated for each monthly flight.

  3. What similar or related data should the user be aware of?


How reliable are the data; what problems remain in the data set?

  1. How well have the observations been checked?

    The surveys were conducted through aerial observations by the pilot/wildlife biologist and another scientific observer on their respective sides of the aircraft. The health values assigned a given area are reflective of the observers. A more formal on-ground assessment would be needed to determine accuracy of attributes.

  2. How accurate are the geographic locations?

  3. How accurate are the heights or depths?

  4. Where are the gaps in the data? What is missing?

    No known omissions. Due to weather or other unforeseen circumstances, flights may not be done monthly.

  5. How consistent are the relationships among the observations, including topology?

    Flight line transects were predetermined before flight. Each and every subsequent flight was flown according to these transects. Observations from both sides of the aircraft were taken every five second along these transects. GPS readings were automatically recorded with each observation.


How can someone get a copy of the data set?

Are there legal restrictions on access or use of the data?

Access_Constraints:
Data generated by the Brown Marsh principal investigators will be available only to the project’s other principal investigators, following the established QA/QC review, for a period of two years. After two years from the finalization of the data, it shall be made available to the public. Please contact the principal investigator for exact date of availability. It is strongly recommended that these data be directly acquired from the Brown Marsh Database Information Management System server and not indirectly through other sources which may have changed the data in some way.
Use_Constraints:
Acknowledgement of the principal investigator 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 these data. 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 mapping conventions, methodologies, data collections and computer processes over time. The principal investigator and the distributor shall not be liable for improper or incorrect use of these data, based on the description of appropriate/inappropriate uses described in this metadata document. The principal investigator and distributor make no claims as to the data’s suitability for other purposes. These data are not legal documents and are not to be used as such.

  1. Who distributes the data set? (Distributor 1 of 1)

    U.S. Geological Survey, National Wetlands Research Center
    c/o Scott Wilson
    Electrical Engineer
    700 Cajundome Blvd
    Lafayette, LA 70506
    USA

    337-226-8644 (voice)
    337-266-8616 (FAX)
    scott_wilson@usgs.gov

    Hours_of_Service: 8:00 am to 4:00 pm CST, Monday thru Friday
  2. What's the catalog number I need to order this data set?

    Brown Marsh Aerial Survey Maps

  3. What legal disclaimers am I supposed to read?

    Although these data have been processed successfully on a computer system at the designated principal investigator’s facility, 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 the official Brown Marsh Database Information Management System server or from the principal investigator, and not indirectly through other sources which may have changed the data in some way. It is also strongly recommended that careful attention be given to the contents of the metadata file associated with these data. The Brown Marsh committee shall not be held liable for improper or incorrect use of the data described and/or contained herein. So, these data are provided as is and without any express or implied warranties. Also, use of trade names or commercial products in the metadata file is solely for the purpose of providing specific information, and does not imply recommendation or endorsement. Any downloading and use of these data signifies a user’s agreement to comprehension and compliance of the disclaimer. Insure all portions of metadata are read and clearly understood before using these data in order to protect both user and principal investigators interests.

  4. How can I download or order the data?

  5. Is there some other way to get the data?

    None


Who wrote the metadata?

Dates:
Last modified: 30-May-2001
Last Reviewed: 25-Sep-2001

Metadata author:
R. Scott Kemmerer
U.S. Geological Survey/NWRC-JWCS
Biologist
700 Cajundome Blvd
Lafayette, LA 70506
USA

337-266-8669 (voice)
337-266-8592 (FAX)
scott_kemmerer@usgs.gov

Hours_of_Service: 8:00 am to 4:00 pm CST, Monday thru Friday
Metadata standard:
Content Standard for Digital Geospatial Metadata (FGDC-STD-001-1998)

Metadata extensions used:


Generated by mp version 2.7.33 on Thu Apr 03 14:23:47 2003