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arXiv · 2508.16750

Estimating Vertical Velocity in Convective Updrafts from Temperature, Pressure, and Latent Heating

Abstract

The vertical velocity in convective clouds ($w_c$) mediates convective anvil development and global moisture transport, influencing Earth's energy budget, but has yet to be estimated globally over long periods due to the absence of spaceborne retrievals. Here, a method for estimating $w_c$ given vertical profiles of in-cloud temperature, pressure, and latent heating rate is presented and assessed. The method relies on analytical models for the approximately linear relationship between $w_c$ and condensation rate ($\dot{q}_{vc}$) in convective clouds, which we derive from steady-state and non-steady-state plume models. We include in our analysis a version of $\dot{q}_{vc}/w_c$ derived from the supersaturation rate in convective clouds, recently presented in Kukulies et al. (2024). We assess the accuracy of $w_c$ estimates against convective cloud simulations run with different model cores and spatial resolutions in both tropical and mid-latitude environments. The velocity estimates exhibit lower uncertainties and higher precision in the tropics than they do in the mid-latitudes. Vertical velocity is estimated to within $\approx1$ m/s for most samples in the tropics. Potential applications, validation against future satellite mission retrievals, and approaches for improving the estimation are discussed.

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BibTeXRIS

Amel Derras-Chouk, Gregory Elsaesser, Zhengzhao Johnny Luo, Toshi Matsui, Andreas F. Prein, Jingbo Wu. 2025-08-22. Estimating Vertical Velocity in Convective Updrafts from Temperature, Pressure, and Latent Heating. https://arxiv.org/abs/2508.16750

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