Hurricane Milton: Expert comments
09 October 2024
Hurricane Milton, a category five hurricane, is closing in on Florida, USA.
Professor Hannah Cloke, Professor of Hydrology at the ºÚ¹Ï³ÔÁÏÍø, said: “Hurricane winds grab people's attention, but flooding is probably the biggest concern with Milton. Winds of 150mph can easily destroy buildings and cause injuries and fatalities if people are caught out in the open by flying debris.
“There are three types of floods that cause the biggest damage - storm surge causing coastal flooding, flash floods from the extremely heavy rain, and river floods as all that water rushes down channels and onto floodplains.
“People's attention may be turned to the sky, but emergency planners will be worried about what is coming from below.”
Professor Liz Stephens, Professor in Climate Risks and Resilience at the ºÚ¹Ï³ÔÁÏÍø, said: “The wide area of intense winds and rainfall from Hurricane Milton will mean that many communities in Florida who are still recovering from the impacts of Hurricane Helene will be affected again by this latest storm, even though Milton is expected to make landfall further south.
"Hurricane Milton is forecasted to track across Florida and out into the North Atlantic Ocean. This means that we are not expecting to see the same flash flooding and mudslide impacts as Helene in areas such as the Appalachian mountains, caused by Helene decaying over land.
"Rising sea surface temperatures as a result of climate change are fuelling the intensity of hurricanes, and the warmer atmosphere can carry more water. This means that the storms which do form are becoming more impactful."
"Further research is needed to understand how the risk of consecutive hurricanes is changing, as these clusters of events can greatly stretch resources for emergency preparedness and response."
Dr Xiangbo Feng, Research Scientist in Tropical Cyclones, said: “Climate change alters the mean state of our climate system. For example, it can make the surface air temperature warmer. This allows the air to be able to hold more moisture (that means potential rainfall could be heavier once conditions for a phase change are met), and change the large-scale background atmospheric circulations in which extreme weathers are embedded. This can shift extreme events to some unusual places or change the propagation of extreme weather systems. Climate change also changes the appearance of extreme weather, such as the frequency, intensity, and persistence. Large-scale extreme weather (e.g. hurricanes) is usually triggered by small-scale disturbances, which occur in our Earth's climate system. With climate change, the climate system has higher instability, and this would generate more finer-scale disturbances that will seed extreme weather.
“Climate science research finds that the current climate change pattern is shifting the number of hurricanes in the North Atlantic higher up. This upward trend is clearly seen in observations over the past 4-5 decades. Our warming climate also strengthens the intensity of tropical storms. The proportion of major hurricanes will likely increase in the future with the warming trend. Note that there is still uncertainty in the frequency and intensity of hurricane for the future. But, for sure, climate change will worsen the impacts of hurricanes, such as excessive rainfall, and storm surges and high waves related to mean sea level rise.
“In the North Atlantic, since 1960, a CAT5 hurricane is seen about every two years. What makes Hurricane Milton stand out is its location when it reaches and maintains such high strength. It is very rare to see a CAT5 hurricane appearing in Gulf of Mexico. Hurricane Milton also has a very slow travelling speed. This allows the storm to stay longer over the ocean and extract sufficient energy from the sea in order to maintain such strength. But this may also mean a longer time for people to prepare and mitigate the impact.”
Dr Helen Hooker, flooding, climate change and tropical cyclones research scientist at the ºÚ¹Ï³ÔÁÏÍø, said: “Hurricane Milton formed in the Gulf of Mexico, which is experiencing record-breaking ocean temperatures.
“Milton developed incredibly quickly and rapidly intensified into a Category 5 hurricane. A drop of around 47 millibars was recorded in just 7 hours, making Milton the most rapidly intensifying hurricane since Wilma in 2005.
“Climate change has contributed in three main ways to the worsening impacts of hurricanes:
“By increasing ocean temperatures as they absorb heat from the atmosphere, giving extra energy to the storm. This contributes to rapid intensification and a higher category hurricane with stronger wind speeds.
“Sea levels have already risen and will continue to do so, making storm surge impacts worse. Higher water levels will penetrate further inland, affecting more people.
“Our warmer atmosphere holds more water, meaning heavier rainfall. More intense rainfall on top of a higher storm surge combines to worsen impacts.”