IBTrACS Version 4 – Faster Updates, Fewer Formats, and Better Support

The International Best Track Archive for Climate Stewardship (IBTrACS) is a collection of global best track data for tropical cyclones. Annual updates of the dataset began in 2008 and since then have expanded to support users in numerous areas. The fourth iteration of IBTrACS provides numerous improvements, the most evident of which is daily updates. Since its inception, IBTrACS has had a long lag between a storms occurrence and its inclusion in IBTrACS. We now include daily updates using working best track information; such storms are denoted as “preliminary” tracks in IBTrACS. This allows for more timely comparisons between active storms and historic storms. The preliminary tracks are replaced when finalized best track data are provided from forecast agencies. Other changes for version 4 include:

• Reduction in the number of formats to simplify support. The formats are: CSV, netCDF, and shapefiles. These files are completely inter-consistent, providing the same information but in different formats.
• More data from the source agencies. This includes providing all columns from HURDAT, JTWC, La Reunion and more variables from BoM.
• Basin files now provide all storms occurring in a given basin (previously, we only included storms that started in the basin, which led to confusion).
• Higher resolution tracks: Many agencies provide storm data at resolutions better than 6-hourly, so we have transitioned to providing 3-hourly points. We continue to provide all observations as provided by the agencies (e.g., all landfall observations in HURDAT are now provided).

The improved IBTrACS version 4 will be available in Spring 2018.