SMILES diurnal variation climatology of strato- and mesospheric trace gases: O3, HCl, HNO3, ClO, BrO, HOCl, HO2, and temperature
We have made a climatology of the diurnal variation of short-lived atmospheric compounds, such as ClO, BrO, HO2, and HOCl, as well as longer life time longer-lived species: O3, the hydrogen chloride isotopes H35Cl and H37Cl, and HNO3 from measurements by the Superconducting SubMIllimeter9 wave Limb-Emission Sounder (SMILES) on International Space Station (ISS). We performed the observation with very low noise on the emission spectrum for measuring of vertical profiles of atmospheric compositions with altitude range from the lower stratosphere to the lower thermosphere (20 – 100 km), thus observing at all local times due to a non-sun-synchronous orbit of ISS. The diurnal variation climatologies are based on data periods of two months. Consideration of the SMILES time-space sampling patterns with respect to the averaging coordinates is a key issue for climatology creation. Biases induced by inhomogeneous sampling are minimized by carefully choosing the size of averaging bins. The sampling biases of the diurnal variation climatology of ClO and BrO are investigated in a comparison of homogeneously sampled model data versus SMILES sampled model data from the stratospheric Lagrangian chemistry and transport model ATLAS. Mostly the relative error is in the range of 0 – 20%.