AIS data

Automatic identification system (AIS) data are used to identify and track vessels for various purposes (primarily navigational safety). These data can be used to study vessel traffic, such as ship routing and speed over ground (SOG). Source data were obtained from the United States Coast Guard Navigation Center (USCG NAVCEN) for the period from June 2008 to December 2015. Derived data resulting from the processing of the source data are described here. This data set presents annual raster data (1 square kilometer grid size) off California from 2008-2015 for cumulative ship traffic density (kilometers/day) and mean SOG (knots; distance-weighted). The universe of data is limited to vessels with a length greater than or equal to 80 meters. The data are analyzed in three groups: freight vessels (container, general cargo, bulk carrier, refrigerated cargo, vehicle carrier, etc.), tanker vessels (crude oil, chemical/products, liquid petroleum gas, etc.) and all vessels (the previously noted vessels, plus passenger vessels and other vessel classes). The data are contained in a file geodatabase format as raster data sets. Metadata for the overall data set are contained at the level of the file geodatabase. The data were generated and used for a research article (Moore et al. 2018):

Moore, T.J., Redfern, J.V., Carver, M., Hastings, S., Adams, J.D., Silber, G.K., 2018. Exploring Ship Traffic Variability off California. Ocean and Coastal Management. https://doi.org/10.1016/j.ocecoaman.2018.03.010

See this manuscript for more information on the data description, issues, and processing methods.

These data were developed to support conservation research related to marine mammal risk assessment (e.g., ship strike risk).

To cite these data please reference:

Moore, T.J., Redfern, J.V., Carver, M., Hastings, S., Adams, J.D., Silber, G.K., 2018. Exploring ship traffic variability off California. Ocean & Coastal Management 163, 515-527. DOI: 10.1016/j.ocecoaman.2018.03.010

Moore, T.J., 2018. Vessel density and vessel speed data off California: 2008-2015, Mendeley Data, v1. DOI: 10.17632/4tgwv45bz8.1

The raster data set names are formatted as follows:

shiptraffic_calif_YYYY_SMOEMO_ATTRIB_lenge80_ENT_prj

YYYY = year (2008-2015)

SMOEMO = start month and end month (jundec or jandec)

ATTRIB = mean vessel density (kmperday) or mean distance-weighted vessel speed over ground (sog)

ENT = type of vessels: frt (freight) or tnk (tanker) or all (frt + tnk + other vessel types).

The universe of vessels is large vessels (>= 80 meters in length). Vessel types are discussed in more detail in the journal article associated with these data and the supplemental online information for that article.

Geographic Extent (Horizontal) and Temporal Extent (Annual)

The data are accessible via Mendeley Data at the following URL:

https://dx.doi.org/10.17632/4tgwv45bz8.1

Downloadable data in the Mendeley Data repository.

No constraints for access to data that are published in the Mendeley Data repository.

If these data are used, please make reference to the following citations:

Moore, T.J., Redfern, J.V., Carver, M., Hastings, S., Adams, J.D., Silber, G.K., 2018. Exploring ship traffic variability off California. Ocean & Coastal Management 163, 515-527. DOI: 10.1016/j.ocecoaman.2018.03.010

Moore, T.J., 2018. Vessel density and vessel speed data off California: 2008-2015, Mendeley Data, v1. DOI: 10.17632/4tgwv45bz8.1

The data were processed and analyzed with ArcGIS Desktop version 10.4.1 software and the Spatial Analyst extension in a Windows 7 environment. The data are stored as raster data sets in a file geodatabase. The overall size of the file geodatabase is about 112 MB.

Some days of data were missing in a few years, and especially in the first year (2008) of data collection/archiving by the USCG.

The data processing methods and quality control procedures are discussed in the following journal article and supplemental online information published with the article:

Moore, T.J., Redfern, J.V., Carver, M., Hastings, S., Adams, J.D., Silber, G.K., 2018. Exploring ship traffic variability off California. Ocean & Coastal Management 163, 515-527. DOI: 10.1016/j.ocecoaman.2018.03.010

The source (raw) data from the USCG were collected from 2012 to 2016 and are not available for dissemination. The processing of the data occurred during the period of 2016-2017. The derived data were made available approximately one year after processing was completed.

Derived data reside in the Mendeley Data repository but a copy can be archived at another resource as deemed suitable. Through Mendeley Data, however, the data are archived on the Data Archiving and Network Services (DANS; https://dans.knaw.nl/en) to preserve the data over the long term.

The derived data were disseminated and archived within approximately one year after the data processing was completed. Mendeley Data is the data repository and has received industry standard certification for this role. The data are stored on Amazon S3 servers to ensure the integrity and security of these data. The source data are secured and protected through encryption with multiple backup copies. Source data are backed up locally and offsite with data protections in place.

Source data should be obtained from the data provider (USCG).