The Dynamics of Idealized Convection Schemes and Their Effect on the Zonally Averaged Tropical Circulation
The Dynamics of Idealized Convection Schemes and Their Effect on the Zonally Averaged Tropical Circulation
复制标题
理想对流方案的动力学及其对纬向平均热带环流的影响
DOI：
10.1175/jas3935.1
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发表时间：
2007
影响因子：
3.1
通讯作者：
D. Frierson
中科院分区：
文献类型：
--
作者：
D. Frierson
本文在理想化的潮湿GCM中考察了简单对流方案对纬向平均热带大气环流的影响，以获得对流对热带大气影响的广泛分类。这是用Betts和米勒风格的简化对流方案来完成的。该计划是利用在潮湿的GCM与简化的物理参数化（灰色辐射，纬向对称，板混合层海洋边界条件）。与没有对流方案的模拟进行比较[即，大尺度凝结（LSC）的唯一]，与湿对流调整（MCA）参数化，并与各种配方和参数集的简化Betts-Miller（SBM）方案。与LSC或MCA模拟相比，使用SBM方案的控制运行，热带变得更安静，对水平分辨率的依赖性更小。Hadley环流质量输送与SBM方案显着减少，是ITCZ降水。决定这种行为的一个重要因素是浅层对流的参数化：如果没有浅层对流，对流方案在网格尺度上防止对流发生的效果很差。对流方案参数的敏感性也进行了检查。的模拟是显着不敏感的对流松弛时间，只有轻度敏感的参考配置文件的相对湿度，提供了显着的大规模冷凝是不允许发生的。在所有的模拟中发生的纬向平均热带环流的变化是根据方案的对流标准和大气的总湿稳定度来理解的。
In this paper, the effect of a simple convection scheme on the zonally averaged tropical general circulation is examined within an idealized moist GCM to obtain broad classifications of the influence of convection on the Tropics. This is accomplished with a simplified convection scheme in the style of Betts and Miller. The scheme is utilized in a moist GCM with simplified physical parameterizations (gray radiation, with zonally symmetric, slab mixed layer ocean boundary conditions). Comparisons are made with simulations without a convection scheme [i.e., with large-scale condensation (LSC) only], with the moist convective adjustment (MCA) parameterization, and with various formulations and parameter sets with a simplified Betts–Miller (SBM) scheme. With the control run using the SBM scheme, the Tropics become quieter and less dependent on horizontal resolution as compared with the LSC or MCA simulations. The Hadley circulation mass transport is significantly reduced with the SBM scheme, as is the ITCZ precipitation. An important factor determining this behavior is the parameterization of shallow convection: without shallow convection, the convection scheme is largely ineffective at preventing convection from occurring at the grid scale. The sensitivities to convection scheme parameters are also examined. The simulations are remarkably insensitive to the convective relaxation time, and only mildly sensitive to the relative humidity of the reference profile, provided significant large-scale condensation is not allowed to occur. The changes in the zonally averaged tropical circulation that occur in all the simulations are understood based on the convective criteria of the schemes and the gross moist stability of the atmosphere.