Tropical cyclones: lesser, more severe
doi:10.1038/nindia.2010.23 Published online 28 February 2010
Climate change is expected to create one problem less for inhabitants of coastal tropical villages and cities — the number of tropical cyclones they fight with every year will become lesser, according to new estimates. However, there's a flip side — the cyclones that do occur are going to be extremely severe.
International meteorological experts reviewing data on past tropical cyclone activity to make future projections say past changes in hurricane activity cannot be distinguished from natural variability, mainly because of incomplete records and large natural fluctuations over time.
However, future projections consistently point to an increase in the most severe tropical cyclones as the climate warms further.
As the storms become more intense, there will be more precipitation in the storm centres.
The team with experts from USA, China, Japan and India says in their report that large amplitude fluctuations in the frequency and intensity of tropical cyclones greatly complicate the detection of long-term trends.
"Trend detection is further impeded by substantial limitations in the availability and quality of global historical records of tropical cyclones," the team, including A. K. Srivastava from India Meteorological Department, Pune, says.
The future projections were based on theory and high-resolution dynamical models. They indicate that greenhouse warming will cause stronger storms, with their intensities increasing between two and 11 per cent by 2100.
Their modelling studies also project decreases in the globally averaged frequency of tropical cyclones, by 6–34%.
In view of the societal impacts of tropical cyclones, the researchers suggest that further research should be carried out on climate-relevant observations, theory and modelling of tropical cyclones and related regional climate changes.
"Models with increasingly fine spatial resolution and new approaches for improving past tropical cyclone records hold substantial promise for reducing uncertainties in both the understanding of causes of past changes, and future projections of tropical cyclone activity," they say in the report.
Knutson, T. R. et al. Tropical cyclones and climate change. Nat. Geosci. 3, 157-163 (2010) | Article |