How will increased greenhouse gases affect the length of the tropical cyclone season?

  • 27 May 2015
  • Number of views: 2887

The timing and duration of the active season for tropical cyclones (TCs) varies throughout the world, and the seasonality of TCs could be impacted as greenhouse gas concentrations increase and our planet warms. Understanding a potential climate change-induced impact on TC seasons is important for accurate projections and for supporting a more climate resilient nation.

Research funded by CPO’s Modeling, Analysis, Predictions, and Projections (MAPP) program, titled “Projected 21st century changes in the length of the tropical cyclone season” by John G. Dwyer (Columbia University) et al., was recently accepted for publication and posted as an Early Online Release in the Journal of Climate. The study used two different methods to examine how the timing of tropical cyclone season is projected to change, for the end of the 21st century compared to the end of the 20th century, due to increased greenhouse gases and other anthropogenic impacts. The two sets of simulations used were a downscaling method applied to CMIP5 and CMIP3 data as well as the NOAA GFDL global atmospheric model (HIRAM) forced with CMIP5 and CMIP3 sea surface temperature anomalies. The simulations gave different projections for the changes in length of the TC season, and ultimately found no consensus on how the length of the TC season will respond to a warming climate. This study was conducted by a number of GFDL scientists as well as several CPO/MAPP-funded academic researchers.

To view the online early release of this paper, go to:



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