Morphology‐Driven Ternary Pattern Space Spans Shallow Marine Clouds

Abstract

Abstract Marine shallow clouds exhibit a variety of patterns, which have been the subject of extensive research. In this study, we introduce a new approach for their continuous classification using Moderate Resolution Imaging Spectroradiometer (MODIS) true color imagery. This method utilizes a ternary phase space derived from the clouds' morphological properties, and defined by three end members: closed‐cell and open‐cell stratocumulus, and Cumulus clouds. We show that a phase space defined by cloud fraction and the number of voids (clear‐sky areas surrounded by clouds) successfully captures the inherent mixture of patterns, providing a more nuanced and objective classification scheme. Focusing on two regions located in the North and South Eastern Pacific, we show that closed cells dominate the eastern parts of the study regions, while mixed states, those not purely representing any end member, dominate the western regions. The mixed states exhibit diverse morphologies, showing that this approach anchors classic patterns within a unified space while revealing the richness and variability of intermediate states. To explore and validate this framework, we combine MODIS cloud properties with radiative fluxes from the Clouds and the Earth's Radiant Energy System (CERES). Examination of cloud microphysical properties shows coherent gradient structures within the phase space, lending support to this classification framework. Importantly, these microphysical distinctions are reflected in corresponding variations in radiative behavior, with the shortwave radiative flux ranging from 100 to 350 across the spectrum of cloud patterns.