The interaction between the Earth's environment and the electrically charged gas known as the solar wind is highly complex and has been under study for decades. We use a universal principle of physics – the relativity principle – to gain physical insight into this interaction. We apply this principle to physical processes that occur during geomagnetic storms. We clarify how the solar wind ultimately causes currents to flow between the Earth's upper atmosphere and space.

This study cross-compares the 10-year record of GPS radio occultation (GPS-RO) specific humidity product against independent databases (e.g., AIRS satellite, NASA/MERRA, and ERA-Interim). Our objective is to investigate the suitability of the GPS-RO humidity as a climate variable, which the science community could use in climate research. GPS-RO offers high vertical resolution, low sensitivity to clouds, and long-term stability making GPS-RO humidity a valuable complementary data set.

We performed a theoretical study of how the Earth’s ionosphere interacts with the tenuous magnetosphere above it. We asked the following: what leads to electric fields and electric currents flowing between these two regions? We concluded that one source of currents flowing between these regions is the localized heating of neutral gas by energetic particles precipitating from above (the magnetosphere).

We have explored the use of COSMIC radio occultation data to provide valuable scientific information on how energetic particles arriving from the Earth’s magnetosphere affect the ionosphere. These precipitating particles significantly alter the Earth’s ionospheric electron density in the E region at altitudes near 120km. This affects the ionospheric conductivity and hence the global electrodynamics and structure of the upper atmosphere during geomagnetic storms caused by the solar wind.