As with Hurricane Katrina three years ago, it was not long after Cyclone Nargis struck the Irrawaddy Delta that headlines emerged questioning the role of climate change in delivering the devastation.
But the fact is that climate science does not have much to say about such individual storms, says noted climate scientist Dr Anond Sanidvongs. Climate modelling can only help us to understand how a warmer climate may influence the likelihood of such storms.
So what is that likelihood?
New research findings on tropical cyclones and climate change were released last week by scientists with the US National Oceanic and Atmospheric Administration (NOAA). They stated that the recent increase in hurricane activity over the Atlantic Ocean was not the result of climate change and was within the range of storm variability scientists should expect.
Additionally, their models showed that warmer temperatures will actually reduce the number of hurricanes in the Atlantic by 18 per cent by the end of the century.
However, Anond advises that we should not take these findings too seriously. He says the researchers did not use models of sufficient detail to be of much value in predicting the likelihood of large storms like cyclones or hurricanes.
“It’s just not the right tool,” Anond said. “The model used a resolution of 20 square kilometres. To really understand the development and movement of cyclones, researchers should be using models with much higher detail, up to 100-200 square metres in resolution.
“To be of much value such models can’t just predict the potential for large storms, but also their duration and size, which cannot be addressed with such a low-resolution study.”
NOAA researchers also acknowledged that their model could not simulate storms with winds in excess of 180kph. Nargis had winds of 190kph when it hit Burma and Hurricane Katrina’s winds were in excess of 200kph.
Anond said the findings also contradicted the UN Intergovernmental Panel on Climate Change, which suggested temperate zones would experience more storms while tropical countries might have fewer but larger storms.
He said it would be some time before climate modelling on a regional scale would contain sufficient detail to properly examine how cyclones evolve in a warmer climate.
“Our geography is unique. We are surrounded by a large body of water, yet we are not islands. We have land and sea areas of equal amounts. We are affected by the convergence of cooler waters of the Pacific Ocean with the warmer waters of the Indian Ocean. Storm variability is a big issue for us,” he said.
He looks forward to undertaking more detailed modelling here.
“This will not change what we already know with virtual certainty about climate change: coastal areas will be hit harder and with greater frequency with heavy rainfall, high winds and storm surges, which will be made worse by rising sea levels.”