Graphical Abstract

Bao, J. and B. Stevens, 2021: The elements of the thermodynamic structure of the tropical atmosphere. J. Meteor. Soc. Japan, 99,
Special Edition on DYAMOND: The DYnamics of the Atmospheric general circulation Modeled On Non-hydrostatic Domains
https://doi.org/10.2151/jmsj.2021-072.
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Plain Language Summary: The two foundations of the tropical atmosphere are that the horizontal temperature in the free troposphere is homogeneous, and the vertical structure follows a moist-adiabatic lapse rate. This study uses simulations from global storm-resolving models to investigate the accuracy of these ideas. Our results show that horizontally the density temperature appears to be homogeneous, but only in the mid- and lower troposphere. Vertically, the tropical atmosphere in saturated convective regions tends to be isentropic (condensed water remaining in the updraft) below the freezing level and pseudo-adiabatic (condensed water/rain falling immediately upon formation) above. However, the tropical mean temperature is substantially colder than that in saturated convective regions because of the impact of entrainment, a process that the saturated air mixes with dry environment, in the lower troposphere.

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