湿有效能量层结分量计算和斜压分量判定的简化及其应用
Simple Calculation of Stratification Component and Determination of Baroclinic Component Strength about Moist Available Energy and Its Application
中文摘要：
根据大气运动方程组，引入了单位质量气块的总能量在气压场非定常情况下和定常情况下，两种不同表达式，对湿有效能量（MAE）的“参考状态”再讨论，省却了对“参考气压”的繁琐计算；将湿有效能量分解为“层结分量”和“斜压分量”两部分，提出了MAE及其层结分量和斜压分量新的收支方程；提出了“有限气柱内平均单位质量气块的层结分量”计算方法和若干计算实例以及斜压分量强度的判定方法。MAE的层结分量与位势不稳定能量相对应，计算表明：抬升作用和负变压使层解分量迅速增强。有限气柱内单位质量气块的层结分量通常与对流有效位能（CAPE）呈正相关关系，但二者性质不同。邢台2016年7月19日夜间至20日凌晨遭受百年一遇的特大暴雨，分析表明：大尺度环流背景、天气尺度系统的发展制约和运行、有利的地形条件、充足的水汽供应和能量输入，促成湿有效能量大量集中释放，是“邢台7.19暴雨”发生的重要原因。
中文关键词：
湿有效能量，参考状态，层结分量，斜压分量，对流有效位能，邢台7.19暴雨
KeyWords：
MAE, reference state, stratification component, baroclinic component, convective available potential energy, torrential rain in Xingtai on 19 July 2016
Abstract：
According to the equations of atmospheric motion, the total energy per unit mass of air block under the case of unsteady and steady pressure field, two different expressions are introduced to discuss the “reference state” of moist available energy (MAE), which saves the tedious calculation of “reference pressure”. MAE is divided into two parts: “stratification component” and “baroclinic component”, and a new budget equation of MAE and its stratification component and baroclinic component is proposed. The calculation method of “stratification component of average unit mass gas block in finite gas column”, some calculation examples and the determination method of baroclinic component strength are proposed. The stratification component of MAE corresponds to the potential instability energy. The calculation shows that the stratification component is rapidly enhanced by uplift and negative pressure. The stratification component of a unit mass gas block in a finite gas column usually has a positive correlation with the convective available potential energy (CAPE), but their properties are different. From the night of 19 July 2016 to the early morning of 20 July 2016, Xingtai suffered a once-in-a-century rainstorm. The analysis shows that the largescale circulation background, the development constraints and operation of the weather scale system, favorable terrain conditions, sufficient water vapor supply and energy input contributed to the large-scale centralized release of wet effective energy, which is an important reason for the “torrential rain in Xingtai on 19 July 2016 ”. Keywords: MAE, reference state, stratification component, baroclinic component, convective available potential energy, torrential rain in Xingtai on 19 July 2016