对流层中大气温度垂直递减率是决定大气静力稳定度的主要因素。基于气温直减率(γ)倾向公式,讨论了影响γ变化的主要物理过程,包括温度平流的垂直差异和垂直运动。"上冷下暖"的温度平流垂直差异导致气温直减率增大,大气层结趋于不稳定,对与之密切相关的气温直减率平流,特别是混合层平流,进行了讨论。垂直运动对气温直减率的影响往往被忽视,且常被视为抬升条件,重点讨论了天气尺度系统强迫的缓慢垂直运动对气温直减率的影响。
The environmental temperature lapse rate is the critical ingredient of static stability for tropospheric atmosphere. Base on the lapse rate tendency equation, the relevant physical processes that affect the local rate of change of lapse rate are discussed, including differential temperature advection and the vertical motion. Warm temperature advection decreasing with height lead to γ increase and stratification tends to instable. This paper discusses the lapse rate advection which is differential temperature advection in essence, especially the mixed layer advection downstream. The influence of vertical movement on the lapse rate is often ignored, and is often regarded as the lifting machanism. This paper pay more attention to the effect of slow vertical movement, which forced by synoptic scale systems, on the lapse rate.