|0||Short integer field where zeros are "no data" and automatically filled in for the remaining shoreline polylines not derived from lidar.|
|0||Zeros are "no data" and serve as place fillers for the lidar shorelines. Actual uncertainty values for lidar are stored in shoreline uncertainty dBase (.dbf) file.|
|USGS||U.S. Geological Survey|
|NOAA||National Oceanic and Atmospheric Administration|
|UT BEG||University of Texas Bureau of Economic Geology|
|lidar||Light detection and ranging (lidar).|
|T or TP with number||NOAA/NOS topographic survey sheet (T- or TP-sheet) with associated registry number|
|USGS Digital Orthophoto||Shoreline derived from a USGS Digital Orthophoto Quad (DOQ).|
|air photo||Shoreline derived from aerial photographs that have had their shorelines transferred to a topo sheet using optical transfer device.|
|ground GPS survey||Shoreline derived from ground GPS survey.|
|rectified air photo||Shoreline derived from digitally rectified aerial photographs.|
|Range of values|
|0||Shoreline month and day are known.|
|1||Shoreline month and day are unknown and default value of 07/01 was used.|
|open ocean||Shoreline on a coast with open ocean wave exposure.|
|Range of values|
This dataset includes shorelines from 151 years ranging from 1850 to 2001 for the Texas east coastal region from Sabine Pass at the Louisiana border to Aransas Pass at the southern end of San Jose Island. Shorelines were compiled from topographic survey sheets, also known as T-sheets (National Oceanic and Atmospheric Administration (NOAA)), aerial photographs (Bureau of Economic Geology, The University of Texas (UT BEG) at Austin), and lidar data (United States Geological Survey/National Aeronautics & Space Administration and UT BEG). Historical shoreline positions serve as easily understood features that can be used to describe the movement of beaches through time. These data are used to calculate rates of shoreline change for the U.S. Geological Survey's (USGS) National Assessment of Shoreline Change Project. Rates of long-term and short-term shoreline change were generated in a GIS using the Digital Shoreline Analysis System (DSAS) version 4.3. DSAS uses a measurement baseline method to calculate rate-of-change statistics. Transects are cast from the reference baseline to intersect each shoreline, establishing measurement points used to calculate shoreline change rates.
Are there legal restrictions on access or use of the data?
Use_Constraints:Public domain data from the U.S. Government are freely redistributable with proper metadata and source attribution. Please recognize the U.S. Geological Survey as the originator of the dataset.
Neither the U.S. Government, the Department of the Interior, nor the USGS, nor any of their employees, contractors, or subcontractors, make any warranty, express or implied, nor assume any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, nor represent that its use would not infringe on privately owned rights. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the USGS in the use of these data or related materials. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
|Data format:||These files (.cpg, .dbf, .prj, .sbn, .sbx, .shp, .shp.xml, and .shx) are a collection of files with a common filename prefix and must be downloaded and stored in the same directory. Together they are the components of the shapefile and include FGDC compliant metadata. in format Shapefile (version ArcGIS 10.0) Esri polyline shapefile Size: 2.05|
These data are available in a polyline shapefile format. The user must have software to read and process the data components of a shapefile.