Guy Carpenter Asia-Pacific Climate Impact Centre Publishes New Report on Thermodynamic Control on the Climate of Intense Tropical cyclones
The Guy Carpenter Asia-Pacific Climate Impact Centre, a joint initiative of Guy Carpenter & Company, LLC, the leading global risk and reinsurance specialist, and the City University of Hong Kong, has published a new paper on how thermodynamic factors influence the development of intense tropical cyclones around the world. According to the paper, thermodynamic factors (the conversion of different forms of energy such as sea surface temperatures, temperature outflow and tropospheric energy) affect tropical cyclone intensity differently in each of the world’s ocean basins. Tropical cyclones are defined as being ‘intense’ when sustained wind speeds exceed 110 mph (177 kmph), and the report indicates that thermodynamic factors have a particular influence on tropical cyclone intensity in the Atlantic basin.
The significant findings of the paper are:
- The impact of thermodynamic factors on tropical cyclone intensity can be measured by examining the relationship between the maximum potential intensity (MPI) of tropical cyclones and the average formation of intense tropical cyclone in a given basin.
- Using this methodology, the report concludes that the Atlantic basin is the only region where thermodynamic factors have a significant impact on the number of intense tropical cyclones. However, dynamic factors such as wind shear also play an important role.
- In all other ocean basins, there is no thermodynamics/tropical cyclone intensity correlation, or the correlation is not statistically significant, because dynamic factors are more dominant.
- The main reason in explaining the difference lies in the unique way tropical cyclones develop in the Atlantic, where thermodynamic factors are important in providing the necessary energy for tropical cyclone development.
- As it is generally accepted that thermodynamic energy is likely to increase with global warming, some models predict that the number of intense tropical cyclones will rise in the future, particularly in the Atlantic. However, it remains unclear how dynamic factors such as wind shear will be affected by climate change.
- Therefore, more research into how climate change will affect dynamic factors and ocean conditions (e.g. the frequency of El Niño events) is required before definitive conclusions can be drawn on how global warming will impact tropical cyclone intensity.