Geomagnetic Virtual Observatories

Description of GVO data product: Geomagnetic Virtual Observatories (GVO) data are derived from satellite magnetic measurements. The GVO data products consists of magnetic field time series regularly distributed in space and time. GVO time series including all field contributions, and those processed to isolate the core field, are available along with estimated errors. The GVO product are designed to make satellite data more accessible to researchers studying the physics of the core dynamo process, and related phenomenon such are secular variation, geomagnetic jerks and rapid core dynamics. In addition, the GVO product also provide valuable information to those interested in investigating magnetospheric and ionospheric magnetic signals on timescales of months and longer. GVO data products of 1, 4 and 12 month cadance are available for the Ørsted mission (1999-2005), the CHAMP mission (2000-2010), the CryoSat-2 mission (2010-2018), the Grace mission (2007-2018, 12 month only) and the Swarm mission (2014-2022). In addition, a composite GVO dataset derived from all the above missions (with the execption of Grace) are available covering 1999-2022. The GVO data products are given as CDF files providing the magnetic field components, the secular variation field components, and their associated error estimates, all provided in a global grid of 300 Geomagnetic Virtual Observatories. For each satellite zip compressed folders contains the CDFs and a ReadMe.txt file which provides details on the datasets and how these where made. References: Hammer, M.D, Finlay, C.C, and Olsen, N. (2021) Applications for CryoSat-2 satellite magnetic data in studies of the Earth's core field variations. Earth, Planets and Space, 73:73. Hammer, M.D., Cox, G. A., Brown, W. J., Beggan, C. D., & Finlay, C. C. (2021). Geomagnetic Virtual Observatories: monitoring geomagnetic secular variation with the Swarm satellites. Earth, Planets and Space, 73(1), 1-22.