The observation of sprites, other transient luminous events and terrestrial gamma-ray flashes shows how the impact of thunderstorms onto the atmosphere extends from the troposphere up to the upper atmosphere and ionosphere. Thunderstorms are responsible for lightning-produced NOx, one of the major sources in the troposphere, for driving troposphere-stratosphere exchange of atmospheric constituents, and may be producing NOx in the upper atmosphere above them through upper atmosphere discharges and ionization. The impact on atmospheric chemistry, together with thunderstorm-driven precipitation, severe weather events, lightning-induced wildfires, but also gravity wave drive of upper atmosphere circulation and global electric circuit recharge, make thunderstorms a key player of the atmosphere and climate.

In a changing climate with increasing surface temperatures and convection, thunderstorm intensity is likely to increase, as consequently is to increase the relevance of thunderstorm-related processes. The CHIMTEA project will analyse satellite measurements of NOx, ozone and other related constituents from the troposphere to the mesosphere to quantify thunderstorm-induced changes and explore how to improve their detectability. MIPAS observations of the upper troposphere to the mesosphere will be retrieved with a 2D tomographic analysis, to account for the horizontal inhomogeneity of the atmosphere, and studied under thunderstorm conditions together with complementary observations from GOMOS. Nadir observations from SCIAMACHY will be used to study tropospheric NOx and ozone soon after thunderstorm activity has faded. The global distribution of thunderstorm activity will be obtained using global lighting data and characterised with meteorological observations, and information about soil moisture content and salinity from the SMOS satellite. Detailed observations of individual thunderstorms and related electrical processes will be used as case studies for a characterisation of their regional chemical impact and to support the analysis at global scales. The adopted multi-satellite approach will allow to produce global estimates of the magnitude and distribution of thunderstorm-induced perturbations and provide recommendations for future related missions such as ESA ASIM.