The USNIC Great Lakes Ice Chart Web Service is made up of Analysis polygon features classes. The Great Lakes Analysis GIS Shapefile and KMZ file are created and loaded into CloudGIS Database for use in the USNIC Great Lakes Ice Chart Web Service from the North American Ice Service daily Great Lakes Analysis coordinated between the U.S. National Ice Center and Canadian Ice Service. The daily Great Lakes Analysis contains SIGRID-3 information on ice conditions that are separated into various fields including total ice concentration, ice types and their respective partial concentrations, and floe size, among others. This analysis is updated daily, valid at 18 UTC, and available at https://usicecenter.gov/Products/GreatLakesData.The SIGRID-3 vector archive format is one of the World Meteorological Organization (WMO) standards for archiving digital ice charts. The U.S National Ice Center (USNIC) creates SIGRID-3 ice charts on a regular basis for a number of regions in the Arctic, Antarctic, Great Lakes and U.S. East Coast. These SIGRID-3 files have two main components: the shapefile containing the ice analysis information (ice polygons and related attributes) and the metadata describing the ice analysis data under the SIGRID-3 format. Current and legacy data for many USNIC products can be found through the USNIC website (https://usicecenter.gov/), the National Snow and Ice Data Center (https://nsidc.org/) or, for the Great Lakes specifically, through the Great Lakes Environmental Research Laboratory (https://www.glerl.noaa.gov/). The joint North American Ice Service analysis from which this USNIC product derives represents ice conditions valid at approximately 1800 UTC but is analyzed from imagery over the preceding 24hrs. Imagery utilized includes synthetic aperture radar (SAR), geostationary imagery such as GOES, polar orbiting imagery such as VIIRS, other optical or infrared sensors prioritized by regency and image quality, and application of an understanding of conditions gained from surface stations, radar, and forecast weather conditions.Update Frequency: Daily at 1800UTCLink to metadataFor questions about the underlying data or other ice datasets, please see https://usicecenter.gov/Contact.Questions/Concerns about the service, please contact the DISS-GIS team.Time Information:This service is not time enabled.

The Digital Surficial Geologic-GIS Map of Minuteman National Historical Site and Vicinity, Massachusetts is composed of GIS data layers and GIS tables, and is available in the following GRI-supported GIS data formats: 1.) a 10.1 file geodatabase (mima_surficial_geology.gdb), a 2.) Open Geospatial Consortium (OGC) geopackage, and 3.) 2.2 KMZ/KML file for use in Google Earth, however, this format version of the map is limited in data layers presented and in access to GRI ancillary table information. The file geodatabase format is supported with a 1.) ArcGIS Pro map file (.mapx) file and individual Pro layer (.lyrx) files (for each GIS data layer), as well as with a 2.) 10.1 ArcMap (.mxd) map document (mima_surficial_geology.mxd) and individual 10.1 layer (.lyr) files (for each GIS data layer). The OGC geopackage is supported with a QGIS project (.qgz) file. Upon request, the GIS data is also available in ESRI 10.1 shapefile format. Contact Stephanie O'Meara (see contact information below) to acquire the GIS data in these GIS data formats. In addition to the GIS data and supporting GIS files, three additional files comprise a GRI digital geologic-GIS dataset or map: 1.) this file (mima_geology.gis_readme.pdf), 2.) the GRI ancillary map information document (.pdf) file (mima_geology.pdf) which contains geologic unit descriptions, as well as other ancillary map information and graphics from the source map(s) used by the GRI in the production of the GRI digital geologic-GIS data for the park, and 3.) a user-friendly FAQ PDF version of the metadata (mima_surficial_geology_metadata_faq.pdf). Please read the mima_geology_gis_readme.pdf for information pertaining to the proper extraction of the GIS data and other map files. Google Earth software is available for free at: http://www.google.com/earth/index.html. QGIS software is available for free at: https://www.qgis.org/en/site/. Users are encouraged to only use the Google Earth data for basic visualization, and to use the GIS data for any type of data analysis or investigation. The data were completed as a component of the Geologic Resources Inventory (GRI) program, a National Park Service (NPS) Inventory and Monitoring (I&M) Division funded program that is administered by the NPS Geologic Resources Division (GRD). For a complete listing of GRI products visit the GRI publications webpage: For a complete listing of GRI products visit the GRI publications webpage: https://www.nps.gov/subjects/geology/geologic-resources-inventory-products.htm. For more information about the Geologic Resources Inventory Program visit the GRI webpage: https://www.nps.gov/subjects/geology/gri,htm. At the bottom of that webpage is a "Contact Us" link if you need additional information. You may also directly contact the program coordinator, Jason Kenworthy (jason_kenworthy@nps.gov). Source geologic maps and data used to complete this GRI digital dataset were provided by the following: U.S. Geological Survey. Detailed information concerning the sources used and their contribution the GRI product are listed in the Source Citation section(s) of this metadata record (mima_surficial_geology_metadata.txt or mima_surficial_geology_metadata_faq.pdf). Users of this data are cautioned about the locational accuracy of features within this dataset. Based on the source map scale of 1:50,000 and United States National Map Accuracy Standards features are within (horizontally) 25.4 meters or 83.3 feet of their actual location as presented by this dataset. Users of this data should thus not assume the location of features is exactly where they are portrayed in Google Earth, ArcGIS, QGIS or other software used to display this dataset. All GIS and ancillary tables were produced as per the NPS GRI Geology-GIS Geodatabase Data Model v. 2.3. (available at: https://www.nps.gov/articles/gri-geodatabase-model.htm).