How the clustering of clouds and storms impacts rainfall extremes?

New climate model shows more extreme rainfall in the tropics with increased temperatures.

Share

Researchers at the Institute of Science and Technology Austria (ISTA) and the Max Planck Institute for Meteorology attempt to determine how cloud and storm clustering affects rainfall extremes in the tropics using a high-resolution global climate model. The model indicates that extreme precipitation events become more severe as temperatures rise.

Hefty rains cause the majority of catastrophic natural catastrophes. To forecast future trends and better understand the mechanisms underlying these events, researchers have been using computer models of Earth’s climate for a number of decades.

To better understand how cloud and storm clustering affects extreme rainfall occurrences, particularly in the tropics, researchers employed an advanced climate model in this study.

With a considerably finer resolution than previous models, this one demonstrated how the increased cloud clustering that comes with global warming causes extreme rainfall events in the tropics to intensify more than predicted by theory.

ISTA postdoc Jiawei Bao used a new state-of-the-art climate model and said, “We can see that when clouds are more clustered, it rains for a longer time, so the total amount of rainfall increases. We also found that more extreme rain over high-precipitation areas happens at the cost of expanding dry areas—a further shift to extreme weather patterns. This is due to how clouds and storms cluster, which we could now simulate with this new climate model.”

Compared to earlier models, this one replicates the climate at a far better resolution. The intricate dynamics of airflow that produce clouds and cause them to gather to form stronger storms were mainly absent from earlier models because they needed to account for clouds and storms in as much detail as possible.

Researchers focused their investigation on the tropics region around the equator, even though the model replicates the entire world at once. They took this action because the production of clouds and storms in that latitude differs from that in other latitudes.

Caroline Muller, Assistant Professor at ISTA, adds, “In collaboration with our colleagues Bjorn Stevens and Lukas Kluft from the Max Planck Institute for Meteorology, our findings add to the growing body of evidence showing that cloud formation on a smaller scale has a crucial impact on the outcomes of climate change.”

Journal Reference:

  1. J. Bao, B. Stevens, L. Kluft, C. Muller. 2024. Intensification of daily tropical precipitation extremes from more organized convection. Science Advances. DOI: 10.1126/sciadv.adj6801

Trending