Atomic Oxygen and Energy Balance in the Mesosphere and Lower Thermosphere
Abstract
We use atomic oxygen concentrations measured by SABER in conjunction with measurements of infrared radiative cooling and solar heating to assess the energy balance in the Earth's mesosphere and lower thermosphere. Atomic oxygen plays a central role, particularly in the mesopause region, through heating due to exothermic chemical reactions. The SABER data reveal approximate balance in global heating and cooling on annual timescales. In the 11-year SABER record there is also clear evidence of the solar cycle variation in all of the heat budget terms including atomic oxygen. Long-term changes in heating and cooling rates appear consistent with each other. Uncertainty in the energy budget is due largely to uncertainty in recombination rate coefficients governing exothermic chemical reactions at mesospheric temperatures. In this talk we will show the multitude of energy budget terms derived from SABER observations, the global energy budget, the variability due to the solar cycle, and the uncertainty in the energy balance. We also examine the constraints on the global atomic oxygen concentration based on energy balance considerations.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2012
- Bibcode:
- 2012AGUFMSA22B..08M
- Keywords:
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- 0310 ATMOSPHERIC COMPOSITION AND STRUCTURE / Airglow and aurora;
- 0340 ATMOSPHERIC COMPOSITION AND STRUCTURE / Middle atmosphere: composition and chemistry;
- 0342 ATMOSPHERIC COMPOSITION AND STRUCTURE / Middle atmosphere: energy deposition;
- 1650 GLOBAL CHANGE / Solar variability