For the first time, gravity wave-induced heating and cooling effects were fully and interactively incorporated into a Martian general circulation model (GCM). Simulations with a comprehensive GCM with an implemented spectral nonlinear gravity wave (GW) parameterization revealed significant thermal effects of GWs in the mesosphere and lower thermosphere (MLT) between 100 and 150 km. Wave-induced heating and cooling rates are comparable with those due to near-IR CO _2 heating and IR CO _2 cooling, correspondingly. Accounting for thermal effects of GWs results in a colder simulated MLT, with the most of cooling taking place in middle-and high-latitudes. In the winter hemisphere, the temperature decrease can exceed 45 K. The colder simulated MLT is in a good agreement with the SPICAM stellar occultation measurements and Mars Odyssey aerobraking temperature retrievals. Our experiments suggest that thermal effects of GWs are probably a key physical mechanism in the MLT missing in contemporary Martian GCMs.
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机译:首次将重力波引起的加热和冷却效果完全并交互地纳入火星总体循环模型(GCM)中。使用已实现的光谱非线性重力波(GW)参数化的综合GCM进行的仿真显示,在100至150 km之间,中层和较低热层(MLT)中的GW具有明显的热效应。相应地,由于近IR CO _2加热和IR CO _2冷却,波引起的加热和冷却速率可与之相比。考虑到GWs的热效应,会导致模拟的MLT较冷,而大部分冷却发生在中高纬度地区。在冬季半球,温度下降可能超过45K。较冷的模拟MLT与SPICAM恒星掩星测量结果和Mars Odyssey航空制动温度检索结果非常吻合。我们的实验表明,GW的热效应可能是当代火星GCM缺少的MLT中的关键物理机制。
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