SOFIE observations and modelling of nitric oxide in the polar mesosphere and lower thermosphere
Abstract
A reservoir of Nitric Oxide (NO) in the lower thermosphere efficiently cools the atmosphere after periods of enhanced geomagnetic activity. Transport from this reservoir to the stratosphere within the winter polar vortex allows NO to deplete ozone levels and thereby affect the middle atmospheric heat budget. As more climate models resolve the mesosphere and lower thermosphere (MLT) region, the need for an improved representation of NO related processes increases.
We use NO observations made by the Solar Occultation for Ice Experiment (SOFIE) instrument onboard the Aeronomy of Ice in the Mesosphere (AIM) satellite in the Antarctic MLT region and compare them to simulations performed by the Whole Atmosphere Community Climate Model with Specified Dynamics (SD-WACCM). The morphology of the simulated NO is in agreement with observations though the long term mean is too high and the short term variability is too low. The NO production and transport processes are investigated using multiple linear regressions and superposed epoch analyses in the SOFIE observations. A similar approach on SD-WACCM data allows us to determine how well these processes are represented in the model and identify possible improvements.- Publication:
-
42nd COSPAR Scientific Assembly
- Pub Date:
- July 2018
- Bibcode:
- 2018cosp...42E1434H