| Typhoon Mitag seen from Korea's communication, ocean and meteorological satellite on Wednesday. Korea's southern and central regions are covered by clouds following the typhoon. Courtesy of the Korean Meteorological Administration |
By Ko Dong-hwan
Korean meteorologists have warned of “super typhoons” hitting the country as climate change increases its effect.
In the past, typhoons at this time of year were rare. But things have changed.
There have been occurrences in 2013 and 2014 and each year from 2016. This year alone there have been three, including Mitag that hit Korea Thursday.
As ocean temperatures get hotter due to global climate change, the threat of super typhoons with wind speeds reaching 56 meters a second ― or 234 kilometers an hour ― grows.
“Super typhoons have never landed in Korea before,” Jeju University's typhoon research center chief Moon Il-joo said.
“The infamous typhoon Maemi that neared Korea in 2004 was a super typhoon when it passed Japan's Okinawa. But as it moved north toward Korea, it met low ocean temperatures and weakened.
“Now, the temperature of the sea surrounding the Korean Peninsula is rapidly rising (as a result of climate change). That raises the risks that, if a typhoon like Maemi comes along again, it will land on Korea as a super typhoon.”
| A commercial town flanking Gyeongpo Lake in Gangneung, Gangwon Province, is flooded from Typhoon Mitag, Thursday, that brought over 300 millimeters of rain. Yonhap |
Such a scenario is possible because the ocean temperature has always been the highest at the onset of fall. That's why the tropical regions of Taiwan and Southeast Asia in November with warm seawater have generated the strongest typhoons. Those typhoons can threaten Korea while maintaining their magnitude if Korean waters are warm enough.
“Based on our 38 years of records, typhoons from Southeast Asian waters to Korea, China or Japan with wind speeds from 33 to 50 meters per second ― the second-highest magnitude category ― have doubled in number,” Moon said. “This could be the result of climate change.”
Other meteorologists also point to climate change as the main cause of high ocean temperatures around the Philippines, where typhoons in the northern Pacific region are generated. Oceans around the Korean Peninsula rose by 0.8 degrees Celsius from 1991 to 2010, and are now 29 degrees on average, which contributes to creating stronger typhoons, according to the experts.
The super typhoon's prediction came after the 18th typhoon, Mitag, in the northern Pacific region reached the southwestern coastal region of Korea, Thursday. It carried central pressure of 965 hectopascals and a top wind speed of 37 meters a second.
The typhoon is the seventh to hit Korea this year, the record annual frequency after 1959 and since 1951, when the country's state weather watchdog, the Korea Meteorological Administration, started monitoring the storms.
| Downpours from Typhoon Mitag on Thursday caused a landslide of rocks and earth over a parked car at the foot of a mountain in Meahwa Village of Uljin County in North Gyeongsang Province. Yonhap |
The reason behind this year's rare high frequency of typhoons, other than climate change, is the North Pacific anticyclone that has been anchored. Early October is when it is pushed down south by cold air from China, shifting to the south or east the anticyclonic edges where typhoons become active.
This year, however, the cold air did not descend, beefing up the static anticyclone and opening the way to typhoons from the south. Mitag and other fall typhoons seen in Korea this year were driven by such atmospheric conditions, according to experts.
“This year, the anticyclone didn't move east but instead expanded to the north and west, leaving ways open to typhoons from the south,” Moon said.
Mitag is unprecedented in its course. Despite being smaller than Lingling and Tapah in September that hit the Korean Peninsula's western and southern coasts, respectively, it directly hit the region. It landed on Mokpo, South Jeolla Province, plowed through to Daegu, and exited through coastal Yeongdeok County in North Gyeongsang Province.
Most typhoons in the past from the Southeast Asian region ended up just drenching the country's southern outskirts and eventually moving toward Japan and the Pacific Ocean.
“Directly hitting the land carries a heavier downpour and stronger gusts, forcing residents to prepare for the worst cases,” Moon said.