Stratosphere‐troposphere exchange

作者：James R. Holton, Peter Haynes, Michael Edgeworth McIntyre, Anne Ritger Douglass, Richard B. Rood, Leonhard Pfister · 发表于：Reviews of Geophysics · 年份：1995 · DOI：10.1029/95rg02097 · 被引用次数：2989 · 研究领域：Atmospheric Ozone and Climate、Atmospheric chemistry and aerosols、Atmospheric and Environmental Gas Dynamics

In the past, studies of stratosphere‐troposphere exchange of mass and chemical species have mainly emphasized the synoptic‐ and small‐scale mechanisms of exchange. This review, however, includes also the global‐scale aspects of exchange, such as the transport across an isentropic surface (potential temperature about 380 K) that in the tropics lies just above the tropopause, near the 100‐hPa pressure level. Such a surface divides the stratosphere into an “overworld” and an extratropical “lowermost stratosphere” that for transport purposes need to be sharply distinguished. This approach places stratosphere‐troposphere exchange in the framework of the general circulation and helps to clarify the roles of the different mechanisms involved and the interplay between large and small scales. The role of waves and eddies in the extratropical overworld is emphasized. There, wave‐induced forces drive a kind of global‐scale extratropical “fluid‐dynamical suction pump,” which withdraws air upward and poleward from the tropical lower stratosphere and pushes it poleward and downward into the extratropical troposphere. The resulting global‐scale circulation drives the stratosphere away from radiative equilibrium conditions. Wave‐induced forces may be considered to exert a nonlocal control, mainly downward in the extratropics but reaching laterally into the tropics, over the transport of mass across lower stratospheric isentropic surfaces. This mass transport is for many purposes a useful mea...