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Publication Date
1 August 2013

Robust Direct Effect of Increasing Atmospheric CO2 Concentration on Global Tropical Cyclone Frequency - A Multi-Model Inter-Comparison



Rising concentration of carbon dioxide (CO2) is expected to affect tropical cyclone (TC) intensity, frequency, and genesis locations through an increase in global mean sea surface temperature (SST). This has been an area of intensive research for the past few decades with increasing use of high-resolution global climate models (GCMs) and various downscaling approaches [see Knutson et al. (2010) for a recent review]. The assumption appears to be that the dominant effect of increasing CO2 on TCs is through an increase in tropical mean SST. However, recent modeling studies suggest that both spatial patterns of SST warming and higher atmospheric CO2 concentrations can significantly affect global and regional TC statistics independent of the global mean SST warming (Vecchi et al. 2008; Zhao et al. 2009; Held and Zhao 2011). In this article we focus on an examination of the direct or fast effect of CO2 on global TC frequency from the multiple models participating in the U.S. CLIVAR Hurricane Working Group (HWG). An understanding of the direct effect of CO2 is important for both near- term TC projections and assessing the impact of geo- engineering schemes on future TC statistics, especially if as a consequence the atmospheric CO2 concentration increases with significantly delayed or alleviated SST warming.

“Robust Direct Effect Of Increasing Atmospheric Co2 Concentration On Global Tropical Cyclone Frequency - A Multi-Model Inter-Comparison”. 2013. Us Clivar Variations 11: 17-23.
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