DOI: 10.6084/m9.figshare.29037401.v1
title: High-Resolution Mapping of Port Dynamics from Open-Access AIS Data in Tokyo Bay

description: Research data published with <i>Hütten, Moritz (2026)</i><i>: </i><i>High-Resolution Mapping of Port Dynamics from Open-Access AIS Data in Tokyo Bay. </i>Geomatics<b> </b>2026, 6(1), 10;<i> </i>https://doi.org/10.3390/geomatics6010010.<b>ais_messages_tokyobay_2024.parquet:</b> Original messages streamed from aisstream.io between July 29, 2024 and October 27, 2024, in parquet format. Each row in the array represents a single message, with the columns:<br>lat: Latitude in decimal degreeslon: Longitude in decimal degreestimestamp: POSIX timestampmmsi: Vessel MMSI numbersog: Self-reported speed over ground, in knotstype: Self-reported vessel typedestination: Vessel destination name (uncleaned)<b>aisdata_binned_tokyobay_2024.tiff:</b> AIS messages binned in cells of approximately 130 square meter, from 91 days of AIS data between 07/28 to 10/27, 2024, collected over aisstream.io, according to Hütten (2026) and used for the receiver location inference therein.<b>vessel_density_tokyobay_2024.tiff:</b> GeoTIFF file with 8 layers, containing the average vessel density in Tokyo Bay from the analysis of 91 days of AIS data between 07/28 to 10/27, 2024, in units of vessels per square kilometer and in lat/lon resolution of 1 arcsec. The individual layers are:all vessels (moving & stationary)all stationary vesselspassenger/high-speed vessels (moving & stationary)other vessels, including fishing (moving & stationary)law enforcement, military vessels (moving & stationary)pilot, tug, rescue, dredging/diving vessels (moving & stationary)cargo vessels (moving & stationary)tanker vessels (moving & stationary)<br><b>speeds_tokyobay_2024.tiff:</b> GeoTIFF file with 1 layer, containing the average speed in each cell of moving vessels in Tokyo Bay from the analysis of 91 days of AIS data between 07/28 to 10/27, 2024, in units of knots and in lat/lon resolution of 1 arcsec.<b>bearing_tokyobay_2024.tiff:</b> GeoTIFF file with 2 layers, containing the average vessel bearing in each cell in Tokyo Bay from the analysis of 91 days of AIS data between 07/28 to 10/27, 2024. The first layer contains the bearing angle clockwise from true North, the second layer the resultant length of the spherical mean in each cell. Lat/lon resolution is 1 arcsec.<b>berth_areas_tokyobay_2024.tiff:</b> GeoTIFF file with 1 layer, labeling 193 berth and anchorage areas inferred in Tokyo Bay from the analysis of AIS data between 07/28 to 10/27, 2024 in Hütten (2026), Section 3. The area value corresponds to the ID in <i>berth_coords_tokyobay_2024.geojson</i> and the publication.<b>berth_coords_tokyobay_2024.geojson:</b> GeoJSON file with 193 berth and anchorage center-of-gravity coordinates inferred in Tokyo Bay from the analysis of AIS data between 07/28 to 10/27, 2024 in Hütten (2026), Section 3. The ID corresponds to the area value in <i>berth_areas_tokyobay_2024.tiff</i> and matches those in the publication. <i>'arrivals_day'</i> gives the number of vessels arriving per day in each area; <i>'dist_coast_m'</i> the distance to coast of the center of gravity in meters and <i>'pier_lonlat'</i> the corresponding position (longitude/latitude in degrees) for berths close to the shore; <i>'likely_type'</i> the number of corresponding vessel types seen arriving in the areas during the analysis period; <i>'n_vessels'</i> the average number of vessels present in the area; <i>'n_vess_per_km2'</i> the same number normalized by the surface <i>'surface_km2'</i> (square kilometers); and <i>'name'</i> the most likely (raw) name inferred from AIS static reports.<b>transit_areas_tokyobay_2024.geojson</b><b>:</b> GeoJSON file with transit areas defined in Hütten (2026), Figure 6, to determine vessel counts and traffic, and their uncertainty.See also related data set <i>Maritime Activities Observed Through Open-Access Positioning Data: Moving and Stationary Vessels in the Baltic Sea</i>.