This article has been reviewed according to Science X's editorial process and policies. Editors have highlighted the following attributes while ensuring the content's credibility: Understanding how wind changes in response to global warming is necessary for accurately modeling climate and weather, identifying risks to infrastructure, and assessing global wind power capacity. Sunlight delivers energy to Earth.
A small part of that energy is converted into atmospheric kinetic energy (i.e., winds), which eventually dissipates into heat and radiates back out to space. This heat exchange process is called the "atmospheric heat engine." But traditional models of this engine depend on complex processes such as cloud microphysics that remain poorly constrained, limiting the models' predictive power. One of the main questions about wind and climate change is why models and observationally constrained reanalysis data show only relatively weak and inconsistent changes in the atmospheric heat engine in response to warming.
Researchers also debate whether a wetter atmosphere is decreasing the efficiency of the heat engine, weakening global wind energy dissipation. A new paper by Malte Jansen and colleagues published in AGU Advances presents a new approach to estimating the work that drives the winds, using just two quantities. The first is the height-weighted radiative energy loss of the atmosphere.
The second is a bulk Bowen ratio—the ratio of the column-integrated upward sensible heat flux to latent heat flux, which reflects how much energy travels upward as warm air versus latent heat in the form of water vapor. The study authors worked from first principles to show how those two factors (the height-weighted radiative energy loss and the bulk Bowen ratio) can explain changes in the heat engine and wind dissipation in various climate scenarios, including today's. They found that increases in radiative cooling in the upper troposphere and a decrease in the bulk Bowen ratio with warming are in competition with each other.
More radiative cooling increases the atmospheric heat engine's work output, whereas a decrease in the bulk Bowen ratio reduces that output. The balance between the two determines changes in the atmosphere's kinetic energy dissipation and shapes how wind responds to a warming world. Under current climate conditions, these opposing mechanisms largely cancel each other out, the study found.
That could explain the relatively weak and inconsistent changes in global wind energy dissipation during the 21st century predicted in comprehensive climate models and atmospheric reanalysis. However, the authors note that near-constant global wind energy dissipation does not imply that the winds don't change at all. Climate change can still lead to significant shifts in atmospheric circulation and regional wind behavior.
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