Predicting convective rainfall over tropical oceans from environmental conditions
Predicting convective rainfall over tropical oceans from environmental conditions
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根据环境条件预测热带海洋上的对流降雨
DOI：
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发表时间：
2016
期刊：
影响因子：
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通讯作者：
M. M. Flores
中科院分区：
文献类型：
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作者：
D. Raymond;M. M. Flores
采用谱弱温度梯度模式的云解析模式，系统地探讨了平均对流降水对热带环境条件变化的响应。模拟降雨的很大一部分方差可以用三个变量来解释：地表湿熵通量、不稳定指数（一种测量低层到中层湿对流不稳定的指标）和饱和分数（一种柱平均相对湿度）。这些计算结果与热带西太平洋、热带大西洋和加勒比地区37个对流案例研究的推断降雨量以及NCEP FNL分析和ERA - Interim再分析进行了比较。该模型在所有这些情况下都显示出显著的预测能力。然而，由于模型的简化，它一直高估了大约三倍的降水。这些计算还表明，在强对流的情况下，饱和分数不是降雨的预测因子。相反，由于水分准平衡过程，饱和分数随降水而变化。
A cloud resolving model in spectral weak temperature gradient mode is used to explore systematically the response of mean convective rainfall to variations tropical environmental conditions. A very large fraction of the variance in modeled rainfall is explained by three variables, the surface moist entropy flux, the instability index (a measure of low to midlevel moist convective instability), and the saturation fraction (a kind of column‐averaged relative humidity). The results of these calculations are compared with the inferred rainfall from 37 case studies of convection over the tropical west Pacific, the tropical Atlantic, and the Caribbean, as well as in the NCEP FNL analysis and the ERA‐Interim reanalysis. The model shows significant predictive skill in all of these cases. However, it consistently overpredicts precipitation by about a factor of three, due possibly to simplifications made in the model. These calculations also show that the saturation fraction is not a predictor of rainfall in the case of strong convection. Instead, saturation fraction covaries with the precipitation as a result of a moisture quasi‐equilibrium process.
影响因子：
3.1
作者：
R. Plant;G. Craig
通讯作者：
R. Plant;G. Craig