This is part of a series of seminars celebrating the 75th anniversary of LDEO.
Title: Enhancement of precipitation extremes by convective organization
Abstract: In this talk, I will discuss how convective organization modulates tropical climate, focusing on precipitation extremes. First I will present results from the Radiative-Convective Equilibrium Model Intercomparison Project (RCEMIP), which provides a common, idealized configuration across an ensemble of ~30 models, including models with explicit convection and those with parameterizations. By removing heterogeneities in boundary conditions and forcing and their resulting dynamical instabilities, RCE focuses attention on moist convective processes and their interactions with radiation and circulation. Models in which convection becomes more organized with warming exhibit super-Clausius-Clapeyeron growth of precipitation extremes, driven by increased updraft area fraction and enhanced precipitation efficiency due to increases in column relative humidity in the moist, aggregated region. These results emphasize that accurately modeling convective organization is crucial to predicting changes in extreme precipitation in a warming climate. Next, I present preliminary results from the recent ORCESTRA/PICCOLO field campaign in the tropical Atlantic in August-September 2024. We combine precipitation retrievals from the SEA-POL radar deployed on the RV Meteor with measurements from other instruments and satellite observations to evaluate relationships between convective organization, precipitation, and radiative processes.
