PNNL

The Science

Wind gusts beneath rain storms over the ocean increase surface evaporation, but how this process influences tropical circulations—a key component of the global climate system—and precipitation remains unclear.

A research team led by scientists at the U.S. Department of Energy's Pacific Northwest National Laboratory found that the additional surface evaporation is an important energy source for driving tropical circulations that create rainfall in areas with weak surface winds, such as the Tropical West Pacific.

The Impact

In the northern Tropical West Pacific, a region with very strong rainfall and weak surface winds, summertime precipitation is often underestimated in Earth system models compared to observations. Researchers found that accounting for surface wind gusts over the ocean produced more realistic model simulations of rainfall patterns.

User Facility: The research used computational resources of the National Energy Research Scientific Computing Center (NERSC), a DOE Office of Science user facility.

Reference: B.E. Harrop, P.-L. Ma, P.J. Rasch, R.B. Neale, C. Hannay, "The Role of Convective Gustiness in Reducing Seasonal Precipitation Biases in the Tropical West Pacific." Journal of Advances in Modeling Earth Systems 10, 961-970 (2018). [DOI: 10.1002/2017MS001157]