Researchers point out that typhoon moving speed is decreasing year by year

If the moving speed of the typhoon is slow, the precipitation in the area on the typhoon route will increase, which will cause great damage due to flood damage and strong wind. According to research team of James Kosin and others who conduct weather research at the American Oceanic and Atmospheric Administration,Tropical cycloneIt is said that the traveling speed of the city has decelerated by about 10% between 1949 and 2016.

A global slowdown of tropical-cyclone translation speed | Nature
https://www.nature.com/articles/s41586-018-0158-3

Hurricanes Are Moving More Slowly, Which Means More Damage: NPR
https://www.npr.org/2018/06/06/616814022/hurricanes-are-moving-more-slowly-which-means-more-damage

In August 2017Hurricane · HerbieRaging in Houston, Texas, the rainfall recorded 370 mm on August 26, 408 mm on August 27. Floods occurred as a result of heavy rain of about 780 mm in only two days, more than 93 people died alone in Houston. Mr. Kosin says "Houston's rainfall is a result of a slow movement of the hurricane."


Mr. Kosin's research team says the cause of the tropical cyclone is decreasing is due to climate change of the earth. In fact, the poles' atmosphere is getting warmer due to global warming, and the pressure difference with the tropical is gradually becoming smaller. As a result, the wind flowing from the tropics toward the poles is weakened, which means that the moving speed of the tropical cyclone is decelerating.

Also, warming the atmosphere due to global warming means that the amount of moisture contained in the air also increases, leading to an increase in rainfall. For this reason, it seems that even if the tropical cyclone is only 10% slower, the actual amount of rain will be doubled.


Mr. Kosin said, "The decline in the tropical cyclone's movement speed leads to long-term exposure of structures to storms, which increases the risk of collapse, and the tropical cyclone's movement speed will decrease He pointed out that there are threats other than heavy rain and wind storms.