A new international study has provided essential insights into how clouds interact with radiation over the Southern Ocean, a key factor in Antarctic weather and climate dynamics and global climate. Published in Journal of Geophysical Research: Atmospheres, the research draws on observations collected between 2017 and 2023 at Escudero Station on King George Island in the Southern Ocean, north of the Antarctic Peninsula, and compares them with outputs from two widely used forecasting and climate models.

The study was led by Dr. Penny Rowe and Dr. Xun Zou (formerly with the Polar Meteorology Group) and was co-authored by Research Professor David Bromwich (Geography/ Atmospheric Sciences Program), and a principal investigator at The Ohio State University’s Byrd Polar and Climate Research Center.

The findings show that the ERA5 reanalysis model produced by the European Centre for Medium-Range Weather Forecasts consistently overestimated incoming sunlight by up to 50 watts per square meter in summer while underestimating infrared heat energy by about 18–22 watts per square meter, likely due to shortages in simulated liquid water in low lying cloud layers. ERA5 is a comprehensive climate dataset that blends observations with advanced modeling to create the best possible reconstruction of past and present weather and climate conditions.

In contrast, the Polar Weather Research Forecasting model (PWRF) produced much smaller errors, particularly during atmospheric river events—large plumes of warm, moist air that can drive significant warming episodes in Antarctica.

After adjusting for biases, the study revealed that clouds produce major seasonal shifts, causing overall cooling in summer and warming in winter. Meanwhile, the inaccuracies in ERA5 led to an underestimation of the period when clouds contribute to warming by about two and a half weeks each year. These results highlight the importance of enhancing cloud representation in climate and weather models to more accurately capture the processes that shape and influence conditions in the Southern Ocean that affect Antarctic climate and global systems.

Learn more about this study.

Related Research Article:

• Observations of Clouds and Radiation Over King George Island and Implications for the Southern Ocean and Antarctica, Journal of Geophysical Research: Atmospheres, 15 September 2025.