Work

A Novel Thermodynamical Predictor of Tropical High‐Cloud Area Coverage: Estimated Anvil‐Outflow Stability

Year: 2025

Type: article

Abstract: The stability at the lapse‐rate tropopause (LRT) was previously defined as the upper‐tropospheric stability (UTS and S UT ) but might underestimate the stability control on high‐level clouds, since there is little direct connection between convective processes and the thermal stratification at the LRT. Here, a novel estimated anvil‐outflow stability (EAS) based on the minimum stability in the upper troposphere is proposed. At the Manus site, the results show that small and large values of the LRT‐based UTS and S UT both correspond to strong divergence and frequent occurrence of high‐level ice clouds. In contrast, smaller EAS corresponds to stronger convective outflows to produce likely more high‐level ice clouds, with a strong negative correlation. In tropics, EAS better explains the geographic distribution of high‐level cloud coverage (HCC) and its temporal variations than UTS and S UT . With a strong linear correlation, EAS is likely a simple useful predictor of HCC.

Source: Geophysical Research Letters

DOI: 10.1029/2025gl115026

Authors: Zhenquan Wang, Jian Yuan

Institution: Nanjing University

Language: English

Topic: Meteorological Phenomena and Simulations

Subfield: Atmospheric Science

Field: Earth and Planetary Sciences

Domain: Physical Sciences

SDG: Climate action

Open Access status: gold

Estimated APC paid: $3,190