Nonmigrating tidal impact on the CO2 15 μm infrared cooling of the lower thermosphere during solar minimum conditions

This paper explores the role of two important diurnal nonmigrating tides, the DE2 and DE3, in the modulation of CO2 15m emissions during the solar minimum year 2008 by (i) analyzing Sounding the Atmosphere using Broadband Emission Radiometry (SABER) CO2 cooling rate data and (ii) photochemical modeling using dynamical tides from the empirical Climatological Tidal Model of the Thermosphere model.

Tidal diagnostics of SABER data shows that the CO2 cooling rate amplitudes for the DE2 and DE3 components are on the order of approximately 20-50% relative to the monthly means, and they maximize around the lower bound (100km) of the analyzed height interval. The photochemical modeling reproduces the observed results, albeit with systematic amplitude differences which is likely related to the uncertainty in the model input backgrounds, especially atomic oxygen.