Exploring the Radiative Effects of Precipitation on Arctic Amplification and Energy Budget

While, in theory, precipitation impacts the Earth’s radiation budget, the radiative effects of precipitation (REP) are poorly understood and excluded from most climate models. Hence, a new study examined the role of REP in the global and regional energy budgets and hydrological cycles, finding that REP significantly contributes to temperature and precipitation variations at different geographical scales, especially in the Arctic warming. This highlights the relevance of including REP in climate modeling for improved accuracy.

One of the key metrics for climate modelling is radiative forcing. Most climate models, including the general circulation models (GCMs), focus on the effects of different atmospheric factors on radiative forcing. However, there are still large uncertainties in satellite observations and multi-model simulations associated with some atmospheric factors. Among them, clouds are a known source of uncertainty in GCMs, leading to radiative biases. However, another possible source of radiative uncertainty is associated with precipitation.

In principle, precipitating particles affect radiative forcing by disrupting incoming shortwave and outgoing longwave radiations. But most conventional GCMs in the Coupled Model Intercomparison Project Phase 6 (CMIP6) treat precipitation diagnostically and exclude the radiative effects of precipitation (REP). Extracting the magnitude of REP in climate models is challenging because of complicated atmosphere-ocean feedback and multi-model variabilities. To this end, a new study, published in npj Climate and Atmospheric Science on 19 June 2024, led by Associate Professor Takuro Michibata from Okayama University investigated the influence of REP on radiative forcing at different geographical scales.

Read more at Okayama University