Comparison of Observed and Modelled Thermospheric Winds Above Northern Scandinavia

Abstract:

ESPAS (www.espas-fp7.eu) is an EU FP7 e-infrastructure project which provides a platform to access many different observations and model results for the near-Earth space environment, and through metadata allows searching for different data sharing a common time, spatial volume, or phenomenon etc.

As part of work to demonstrate a use case for ESPAS, the Met Office has compared modelled thermospheric winds above northern Scandinavia with observations available through ESPAS. This has principally relied upon winds from UCL's CMAT2 model (also available through ESPAS), which are compared to wind observations made using UCL's Fabry-Perot interferometer (FPI) measurements of airglow above sites such as Svalbard and Kiruna.

We will present the results of these comparisons, discussing them in the context of assessing thermospheric model performance, notably as independent measurements when considering data assimilation experiments, but also for gross model issues such as polar cap convection cell positions.

Further work will also be presented, refining the FPI-model comparison using collocated incoherent scatter radar measurements from EISCAT to distinguish times where the FPI measurements are likely to be contaminated by auroral emissions at lower altitudes than the airglow emissions, thereby ensuring FPI measurements are only compared to model winds at the appropriate altitude.