论文标题
在3D GCM模拟下粘合粉1214b中收敛时间极长
Extremely long convergence times in a 3D GCM simulation of the sub-Neptune Gliese 1214b
论文作者
论文摘要
我们提出了潮汐锁定的迷你新持续GJ 1214b的灰色气体循环模型（GCM）模拟。在1,000-10,000地球天的时间尺度上，我们的结果与以前对同一星球的研究相当，因为它们都表现出两个赤道向东的喷气机。在更长的整合时间（50,000-250,000地球天）中，我们发现循环和观察性特征有明显不同。区域均值的流量从两个赤道喷气机到具有较高速度并更深延伸的单个宽赤道射流的Zonal均值过渡。热点位置在整合时间内也向东移动。我们的结果意味着收敛时间比以前研究中使用的典型整合时间更长。我们证明，这个较长的收敛时间与深层大气的漫长辐射时间尺度有关，并且可以通过一系列简单的参数来理解。我们的结果表明，必须特别注意在系外行星GCM模拟中对收敛时间进行建模，并且可能需要重新审视具有较厚气氛的潮汐锁定系外行星的其他结果。
We present gray gas general circulation model (GCM) simulations of the tidally locked mini-Neptune GJ 1214b. On timescales of 1,000-10,000 Earth days, our results are comparable to previous studies of the same planet, in the sense that they all exhibit two off-equatorial eastward jets. Over much longer integration times (50,000-250,000 Earth days) we find a significantly different circulation and observational features. The zonal-mean flow transitions from two off-equatorial jets to a single wide equatorial jet that has higher velocity and extends deeper. The hot spot location also shifts eastward over the integration time. Our results imply a convergence time far longer than the typical integration time used in previous studies. We demonstrate that this long convergence time is related to the long radiative timescale of the deep atmosphere and can be understood through a series of simple arguments. Our results indicate that particular attention must be paid to model convergence time in exoplanet GCM simulations, and that other results on the circulation of tidally locked exoplanets with thick atmospheres may need to be revisited.
