One of the most costly effects of climate change will be its impact on
extreme weather events, including tropical cyclones (TCs). Understanding
these changes is of growing importance, and high resolution global climate
models are providing potential for such studies, specifically for TCs.
Beyond the difficulties associated with TC behavior in a warming climate,
the extratropical transition (ET) of TCs into post-tropical cyclones
(PTCs) creates another challenge when understanding these events and any
potential future changes. PTCs can produce excessive rainfall despite
losing their original tropical characteristics. The present study examines
the representation of PTCs and their precipitation in three high
resolution (25-50 km) climate models: CNRM, MRI, and HadGEM. All three of
these models agree on a simulated decrease in TC and PTC events in the
future warming scenario, yet they lack consistency in simulated regional
patterns of these changes, which is further evident in regional changes in
PTC-related precipitation. The models also struggle with their represented
intensity evolution of storms during and after the ET process. Despite
these limitations in simulating intensity and regional characteristics,
the models all simulate a shift toward more frequent rain rates above 10
mm/hr in PTCs. These high rain rates become 4-12% more likely in the
warmer climate scenario, resulting in a 5-12% increase in accumulated
rainfall from these rates.