IAA authors:
Lopez-Valverde, Miguel Angel;Brines, Adrian;Modak, Ashimananda;López-Moreno, José Juan
Authors:
Yoshida, Nao;Nakagawa, Hiromu;Aoki, Shohei;Erwin, Justin;Vandaele, Ann Carine;Daerden, Frank;Thomas, Ian;Trompet, Loïc.;Koyama, Shungo;Terada, Naoki;Neary, Lori;Murata, Isao;Villanueva, Geronimo;Liuzzi, Giuliano;Lopez-Valverde, Miguel Angel;Brines, Adrian;Modak, Ashimananda;Kasaba, Yasumasa;Ristic, Bojan;Bellucci, Giancarlo;López-Moreno, José Juan;Patel, Manish
Journal:
Geophysical Research Letters
Abstract:
Using the Nadir and Occultation for MArs Discovery instrument aboard Trace Gas Orbiter, we derived the CO/CO<SUB>2</SUB> profiles between 75 and 105 km altitude with the equivalent width technique. The derived CO/CO<SUB>2</SUB> profiles showed significant seasonal variations in the southern hemisphere with decreases near perihelion and increases near aphelion. The estimation of the CO/CO<SUB>2</SUB> profiles with a one-dimensional photochemical model shows that an altitude-dependent eddy diffusion coefficient better reproduces the observed profiles than a vertically uniform one. Our estimation suggests that the eddy diffusion coefficient in L<SUB>s</SUB> = 240-270 is uniformly larger by a factor of ∼2 than that in L<SUB>s</SUB> = 90-120 in the southern hemisphere, while they are comparable in the northern hemisphere. This fact demonstrates that the eddy diffusion coefficient is variable with season and latitude.
URL:
https://ui.adsabs.harvard.edu/#abs/2022GeoRL..4998485Y/abstract
Keywords:
Mars;eddy diffusion coefficient;atmospheric composition;mesosphere;spectroscopy;retrieval