This report contains several data layers (or themes) that can be used to create views of the sea floor in eastern Long Island Sound and western Block Island Sound. GeoTIFFs produced from the NOAA multibeam bathymetric survey are provided in geographic and Universal Transverse Mercator (Zone 18). Grids of the multibeam bathymetric data, which are provided in original and hill-shaded (i.e. sun-illuminated) versions, are also provided in geographic and Universal Transverse Mercator. Available vector data include polygon data layers that provide the coastline for the Massachusetts GIS project area and an interpretive data layer.

Data layers are provided with geographic coordinates to allow the data to be integrated into a Geographic Information System (GIS). A GIS is defined as a system of hardware and software to support the display, manipulation, and analysis of spatial data for mapping and complex data solving. This integrated package provides researchers the ability to integrate, analyze and map the various datasets to help with economic and social policy-making decisions regarding the environment.

Data layers archived here should not require additional processing to be utilized within the Environmental Systems Research Institute's (ESRI) ArcView and ArcGIS software. This does not mean that a user will not wish to do additional processing, especially if utilizing a different GIS software package or spheroid, but that it is not necessary to do additional processing simply to utilize the data in its minimum archive format

For those who don't have the ESRI software or a compatible GIS data browser available on their computer, a free viewer, ArcExplorer, is available from ESRI here. The key functionality of ArcExplorer is the viewing of spatial data. The user will need to add the selected data layers by using ArcExplorer's add data button.

Each GIS data layer from this publication is cataloged below for easy access. The individual data layers are described below and include the GeoTIFF, grid, or shapefile name (e.g. h11250_utm18_2mmbes.tif) which is linked to a browse graphic showing the data layer extent and coverage. Selecting the data layer name will result in the browse graphic being displayed in a separate browser window.

Federal Geographic Data Committee (FGDC) metadata for the individual data layers is provided in a text version. Selecting associated metadata files from the table below will open the information in a new browser window. A 'zip' compressed, downloadable archive file containing the components of the ArcView shapefile for each data layer is also provided. Compressed downloadable files were created using the Windows program WINZIP v8.0. For those users who do not have software capable of uncompressing the archived zip files, they may obtain a free version of the software from Winzip Computing, Inc. or Pkware, Inc.

Multibeam Bathymetric Imagery

Multibeam Bathymetric Grids

Interpretative Data Layer

Basemap Data