Hurricane “Ian” confirms scientific findings: climate change is increasing the destructive power of hurricanes.
Hurricane Ian caused extreme devastation in the US states of Florida and South Carolina, and many people died. With wind speeds of up to 240 kilometers per hour, it was the fifth strongest cyclone ever to make landfall in the United States. Earlier last week, Typhoon Noru struck the Philippines and Vietnam, with similar devastation as a result. Shortly before, Hurricane Fiona had hit Puerto Rico and the east coast of Canada. What these hurricanes have in common is that some of them intensified unusually quickly and raged with great intensity. A general trend behind which is apparently climate change.
The world today is around 1.2 degrees warmer on global average than before the start of the industrial age around 1850. The number of tropical cyclones – called hurricanes, typhoons or cyclones depending on the region – has not increased on average since then. However, the storms have become stronger, they are bringing more water with them – and they are moving more slowly, increasing local destruction.
Cyclones can occur in the tropics when the water temperature on the surface of the sea is at least 26 degrees. And temperatures are rising in the oceans, which are absorbing large amounts of the extra heat in the Earth system. Average surface temperatures today are around 0.8 degrees above the 20th century average. As a result, hurricanes increase in intensity more quickly. In addition, the warmer air also stores more moisture. This helps hurricanes last longer once they reach shore. In addition, the amount of water that falls as rain increases.
Hurricane Ian fits into this picture. It was the seventh storm with wind speeds of more than 200 kilometers per hour to hit the US coast in the past five years. It is thus in hurricane category four, the frequency of which has increased significantly in recent decades. According to US climate researchers, a new pattern of hurricanes has emerged, which could be observed in 16 of the 20 hurricanes of the past two years: The hurricanes accelerate dramatically in the hours before landing over the heated sea surfaces. After that, they slowly move across the country, dumping large amounts of rain.
Climate researcher Karthik Balaguru of the Pacific Northwest National Laboratory in Washington state explained that “hurricane acceleration rates” are increasing. “Ian,” for example, was a simple 75 mph tropical storm two days before hitting Southwest Florida, which then quickly grew into a Category Four hurricane that doubled its speed. “That worries us,” he told the Washington Post. One of the most disturbing things about climate change is the shifting extremes.
“IAN”: THE DAMAGE FROM THE CYCLONE BECOMES MORE CLEAR
The extent of the devastation caused by Hurricane Ian in Florida became clearer over the weekend. In addition to completely flattened residential areas, destroyed bridges and power lines, the number of fatalities increased. The storm caused massive destruction in the coastal cities of Cape Coral and Fort Myers. Even inland, “Ian” caused flooding.
US President Joe Biden and his wife Jill are expected in Florida on Wednesday. Before his visit to Florida, Biden planned to travel to Puerto Rico on Monday to see the devastation caused by Hurricane Fiona.
The Florida District Medical Commission confirmed 58 deaths on Sunday. The governor of North Carolina said four people had died in his state as a result of the hurricane. The “New York Times” and the broadcaster “CBS”, on the other hand, report around 80 deaths. Meanwhile, rescue teams continued to search for victims. The US Coast Guard, meanwhile, said it was halting the search for 16 migrants who were missing since their boat capsized during the hurricane.
Reconstruction in the region will take months to years, according to Florida authorities. The US government has announced that it will provide up to $40,000 in aid to people without flood insurance. However, the emergency services are still busy reducing the acute danger to the people. Buildings that are in danger of collapsing, as well as power lines and trees that are in danger of tipping over, must be secured. There is a curfew in the evening.
The police cordoned off particularly devastated areas . The schools are closed, and supermarkets, pharmacies and restaurants are also closed for the time being. Long queues have formed in front of the few shops and gas stations that are open on an emergency basis. dpa/afp
The fact that the hurricanes move less quickly is also considered to be the result of a change in large-scale air currents caused by climate change. This makes hurricanes more likely to slow down or even hover over one location, increasing their destructive power. A study by the US weather agency NOAA showed that the mean speed of hurricanes in the North Atlantic decreased by 17 percent between 1944 and 2017.
A particularly dramatic example of such an almost stationary cyclone is “Harvey”, which swept over the Texas metropolis of Houston for three days in 2017, where it released record amounts of rain and caused severe flooding. A climate research team later found that climate change had made this event three times more likely. A recent study by Lawrence Berkeley National Laboratory on “Ian” now shows that the storm brought at least ten percent more rain than would have been the case without climate changes.
But there is another phenomenon that increases the danger posed by hurricanes: the rise in sea level caused by the melting of glaciers and ice caps and the expansion of water with warming. The storms push the seawater towards the shore as they approach. A rise in sea level then means that the tidal waves get higher, move further inland and reach more settlements. A recent example of the impact is the city of Fort Myers, Florida, where sea levels are about 13 inches higher today than they were in the early 20th century. The storm surge caused by “Ian” reached a height of up to 3.70 meters there. The city was badly devastated.
However, climate change is not solely to blame for the fact that hurricanes are causing ever greater damage. One cause is the trend to build settlements on vulnerable stretches of coast. In the decade from 2010 to 2020, the population in the “sunshine state” of Florida grew twice as fast as that of the USA as a whole – by almost 15 percent. Houses on the Atlantic coast are also popular. In doing so, humans endanger themselves twice over: they change the climate, making the hurricanes more devastating, and they also stand directly in their way.
