Forces of nature
Mangkhut has hit with destructive winds, Florence has wreaked havoc with rain
Nature expresses its fury in sundry ways. Two deadly storms — Hurricane Florence and Typhoon Mangkhut — roared ashore on the same day, half a world apart, but the way they spread devastation was as different as water and wind.
Storms in the western Pacific generally hit with much higher winds and the people who live in their way are often poorer and more vulnerable, Princeton University hurricane and climate scientist Gabriel Vecchi said yesterday. That will likely determine the type of destruction.
Mangkhut made landfall on Saturday on the northeastern tip of Luzon island in the Philippines with top-of-the-scale Category 5 winds of 265km/h. Florence had weakened to a Category 1 storm with 145km/h winds by the time it arrived at North Carolina’s coast.
Yet a day later the faster-moving Mangkhut was heading across the South China Sea and last night made landfall in south China’s Guangdong province, with torrential rains and weakened winds of 162km/h.
Florence, meanwhile, was still plodding across South Carolina at a pace slower than a normal person walks. By yesterday, it had already dumped more than 75cm of rain, a record for North Carolina.
Experts say Mangkhut may well end up being the deadlier storm. As of yesterday afternoon, the death count in the Philippines was at least 36, which was still far below that of other storms that have hit the disaster-prone island nation. Police last night said at least 40 people, mostly gold miners, were feared trapped in a landslide in the north. And with Mangkhut now arrived in the densely populated southeast coast of China, it looks likely to cause more death and destruction.
The death toll from Florence stood at 12 yesterday. Its watery insured damage total will eventually be higher, said Ernst Rauch, head of climate research for the world’s largest reinsurer Munich Re.
That’s because of a combination of geography, climatic conditions and human factors.
The western Pacific has two-anda-half times more storms that reach the minimum hurricane strength of 119km/h. It has three-and-a-half times more storms that reach major hurricane strength of 178km/h, and three times more accumulated energy out of those hurricanes, an index that measures not just strength and number of storms but how long they last, according to more than 65 years of storm data .
So far this year 23 named storms have hit the western Pacific and 10 in the Atlantic, both regions more than 30 per cent busier than average years. Hurricanes and typhoons are the same type of storm; both are tropical cyclones, but those in the Pacific west of the International Date Line are called typhoons.
The water in the western Pacific is warmer, and warm water fuels storms. There are also only a few pieces of land to get in the way and weaken them, said University of Miami hurricane researcher Brian McNoldy.
“If we are ever going to have a Category 6 [a speculated-on level that’s above current measurement tools], the western Pacific is where it’s going to be,” said meteorologist Ryan Maue of weathermodels.com.
The Philippines tends to get hit nearly every year, the Carolinas far less frequently, Maue said. That shows another big difference in the storms. Mangkhut formed further south and stayed south — over warmer water. Florence was out of the tropics when it hit land. Because of that, Florence was weakened by the dry air and upper-level winds of the higher latitudes. Not so the more southerly Mangkhut, which, Maue said, “essentially had a perfect environment to intensify to a Category 5 and stay there”.
“Mangkhut and Florence are certainly different animals,” said Colorado State University hurricane researcher Phil Klotzbach. Because Florence is moving so slowly, he said, it will dump more rain than Mangkhut, which is named for the Thai word for the mangosteen fruit.
Both storms have lasted a long time, especially Florence which formed all the way over near Africa 15 days before landfall, McNoldy said. Both storms cover a large area, but
Mangkhut still dwarfs Florence. Mangkhut’s tropical storm force winds stretched more than 525km from the centre, while Florence’s spread about 315km, Klotzbach said.
Economics also play a role in a storm’s impact. As a developing country, the Philippines is much poorer than the southeastern United States, which means houses tend to be less sturdy and first responders less well equipped, among other factors. This is one reason why, when disaster does strike, the effects can be devastating. In 2013, one of the most powerful storms on record, Typhoon Haiyan , killed 7300 people and displaced more than 5 million when it swept across the islands of the central Philippines.
Straddling the famous Pacific Ring of Fire, the Philippines is also bedevilled by volcanoes and earthquakes, and while there are considerable patches of poverty in North and South Carolina, it is not the same as the rural area where Mangkhut hit.
Munich Re’s Rauch said about 30 to 50 per cent of storm damage is usually insured in the US but often less than 10 per cent in developing countries, meaning nine-tenths of the people hit will end up shouldering a bigger economic burden.
In the US, “you can’t move houses, but people can move out of the way”, reflecting mounting damages from storms and often lower losses in life, Vecchi said.
As the world warms from the burning of fossil fuels, the globe will see both more extremely intense storms like Mangkhut and wetter storms like Florence, he said.