World - Expect Fewer, but More Destructive Landfalling Tropical Cyclones
A study based on new high-resolution supercomputer simulations, published in this week's issue of the journal Science Advances, reveals that global warming will intensify landfalling tropical cyclones of category 3 or higher in the Indian and Pacific Oceans, while suppressing the formation of weaker events.
Tropical cyclones (including typhoons and hurricanes), are the most fatal and costliest weather disasters on our planet. Millions of people are affected every year by the destructive power of these extreme weather systems, but how tropical cyclone properties - in particular in coastal areas - will change in response to global warming has long remained a mystery. To address this question, scientists for over two decades have used the world's largest supercomputers to run climate model simulations that show important aspects of these destructive storms. However, until recently the computing power has been insufficient to capture both atmospheric details and resolve the full interaction with the ocean on a global scale.
A team of researchers from South Korea's IBS Center for Climate Physics (ICCP) at Pusan National University recently completed one of the most computing-intensive and detailed global warming simulations so far. The global climate model records small-scale atmospheric and oceanic processes with a horizontal scale of 25 km and 10 km, respectively. This unprecedented resolution is adequate to simulate tropical cyclones and oceanic cold wakes (Fig. 1), which are generated when a strong slowly moving tropical cyclone brings cold deep water up to the ocean surface, further influencing the track and intensity of tropical cyclones.
To determine the sensitivity of tropical cyclones to global warming, the research team ran computer model simulations for present-day atmospheric greenhouse gas composition and doubled and quadrupled CO2 concentrations.