image: Observed Trend in Tropical Cyclone Frequency of Occurrence (1980-2018). view more
Credit: Image credit: Hiroyuki Murakami
Researchers report spatially varying changes in tropical cyclone activity suggesting that climate change is influencing cyclone patterns. Climate models project that global warming will influence tropical cyclone activity, but a short record of satellite observations and the potential confounding effect of multidecadal variability have complicated efforts to discern effects. Hiroyuki Murakami, Pang-Chi Hsu, and colleagues used observations between 1980 and 2018 to quantify changes in tropical cyclone activity and high-resolution dynamical models to infer causes of change. The authors found that cyclone frequency decreased in the southern Indian Ocean and western North Pacific and increased in the North Atlantic and central Pacific. Modeling suggested that external forcing agents, such as greenhouse gases, aerosols, and volcanic eruptions, were likely explanations for the variation in activity rather than multidecadal internal variability alone. The spatial variation of cyclone activity change may be attributable to regional effects of external forcing. According to the authors, the signal of climate change is evident in tropical cyclone spatial distribution, and models suggest decreases in the number of global tropical cyclones toward the end of the century as the effect of atmospheric greenhouse gases becomes widespread in the tropics.
Article #19-22500: "Detected climatic change in global distribution of tropical cyclones," by Hiroyuki Murakami et al.
MEDIA CONTACT: Hiroyuki Murakami, National Oceanic and Atmospheric Administration/Geophysical Fluid Dynamics Laboratory, Princeton, NJ; tel: 609-452-5824; e-mail: hir.murakami@gmail.com
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Journal
Proceedings of the National Academy of Sciences