The data here are updated in near real-time and are kept on this site for several months. For more historic data and for detailed descriptions of INTERMAGNET IAGA2002 file format, visit the Intermagnet website.
If you'd like to download this data at a regular interval we recommend a tool like wget.
Access to the data is provided as-is, without any additional promises to respond quickly to outages, data quality, etc. We request that you acknowledge the USGS Geomagnetism Program in all published documents which make use of our data. Thank you for your interest in the USGS.
Definitive data, consisting of one-minute, hourly-mean, and daily-mean values from USGS observatories from the year 1985 onward are available online. Intermagnet has definitive data available for download, including USGS data. The most recent definitive data typically becomes available within a year of the end of the previous calendar year. USGS currently has an interactive data downloader in beta testing, which will provide download for USGS preliminary and definitive data directly from USGS.
USGS Geomagnetism Program Data, Inquiries and Specialized Data Requests
Duff C Stewart
Data Management: Software Developer