AIS Vessel Tracks 2021
A vessel track shows the location and characteristics of commercial, recreational, and other marine vessels as a sequence of positions transmitted by an Automatic Identification System (AIS). AIS signals are susceptible to interference and this can result in a gap within a vessel track. Vessels can have one or more tracks of any length. Furthermore, tracks will not necessarily start or stop at a well defined port, or when a vessel is not in motion. The distribution, type, and frequency of vessel tracks are a useful aid to understanding the risk of conflicting uses within a certain geographic area and are an efficient and spatially unbiased indicator of vessel traffic. The vessel track positions in this data set are collected and recorded from land-based antennas as part of a national network operated by the U.S. Coast Guard. These tracks were used to build the respective AIS Vessel Transit Counts 2021 layer, in which a single transit is counted each time a vessel track passes through, starts, or stops within a grid cell.
AIS Vessel Transit Counts 2021
Vessels traveling in U.S. coastal and inland waters frequently use Automatic Identification Systems (AIS) for navigation safety. The U.S. Coast Guard collects AIS records using shore-side antennas. These records have been filtered and converted from a series of points to a set of track lines, and then summarized at a 100 m grid cell resolution. A single transit is counted each time a vessel track passes through, starts, or stops within a grid cell. All vessel types have been included in this summary, including null and none reported types.
INFO: Open of `AISVesselTracks2021.gpkg' using driver `GPKG' successful. 1: AISVesselTracks2021 (Multi Line String)
ogrinfo -so AISVesselTracks2021.gpkg AISVesselTracks2021
INFO: Open of `AISVesselTracks2021.gpkg' using driver `GPKG' successful. Layer name: AISVesselTracks2021 Geometry: Multi Line String Feature Count: 6962768 Extent: (-169.111954, 10.773780) - (-60.000584, 51.578117) Layer SRS WKT: GEOGCRS["NAD83", DATUM["North American Datum 1983", ELLIPSOID["GRS 1980",6378137,298.257222101, LENGTHUNIT["metre",1]]], PRIMEM["Greenwich",0, ANGLEUNIT["degree",0.0174532925199433]], CS[ellipsoidal,2], AXIS["geodetic latitude (Lat)",north, ORDER, ANGLEUNIT["degree",0.0174532925199433]], AXIS["geodetic longitude (Lon)",east, ORDER, ANGLEUNIT["degree",0.0174532925199433]], USAGE[ SCOPE["Geodesy."], AREA["North America - onshore and offshore: Canada - Alberta; British Columbia; Manitoba; New Brunswick; Newfoundland and Labrador; Northwest Territories; Nova Scotia; Nunavut; Ontario; Prince Edward Island; Quebec; Saskatchewan; Yukon. Puerto Rico. United States (USA) - Alabama; Alaska; Arizona; Arkansas; California; Colorado; Connecticut; Delaware; Florida; Georgia; Hawaii; Idaho; Illinois; Indiana; Iowa; Kansas; Kentucky; Louisiana; Maine; Maryland; Massachusetts; Michigan; Minnesota; Mississippi; Missouri; Montana; Nebraska; Nevada; New Hampshire; New Jersey; New Mexico; New York; North Carolina; North Dakota; Ohio; Oklahoma; Oregon; Pennsylvania; Rhode Island; South Carolina; South Dakota; Tennessee; Texas; Utah; Vermont; Virginia; Washington; West Virginia; Wisconsin; Wyoming. US Virgin Islands. British Virgin Islands."], BBOX[14.92,167.65,86.46,-47.74]], ID["EPSG",4269]] Data axis to CRS axis mapping: 2,1 FID Column = OBJECTID Geometry Column = Shape MMSI: Integer (0.0) TrackStartTime: DateTime (0.0) TrackEndTime: DateTime (0.0) VesselType: Integer (0.0) Length: Real (0.0) Width: Real (0.0) Draft: Real (0.0) DurationMinutes: Integer (0.0) VesselGroup: String (25.0)