A Hokkaido University research team has developed a method to determine the wind speed in the eye of a typhoon based on meteorological satellite images.
The team hopes to continuously monitor wind speeds and use the data to help with the swift assessment of damage risks if a typhoon makes landfall. The wind speed in the center of a typhoon is proportional to the wind speed near the surface of Earth.
The method was developed using images taken by the Himawari-8 weather satellite, which can take pictures at 2-1/2-minute intervals depending on the sea area. The team was able to estimate the rotation speed of the eye of a typhoon based on its ever-changing position and shape, and to determine the wind speed every few hours.
Using images and observation data recorded in the eye of a typhoon by an airplane, the team was able to confirm the accuracy of its method by comparing the estimated values with the actual measurements recorded in the air.
The Japan Meteorological Agency and other research institutes around the world estimate wind speeds of typhoons and other tropical cyclones based on such factors as the storm's shape. However, in the case of a rapidly developing typhoon, it has been difficult to accurately determine the wind speed until now.
"We hope to improve the accuracy even more through further research," said Meteorology Prof. Takeshi Horinouchi, a member of the Hokkaido University team.
Nagoya University Prof. Kazuhisa Tsuboki, who specializes in meteorology, said: "The achievement makes it possible to measure the speed in the eye of a typhoon, which has been difficult to do until now. It's a major accomplishment that can be expected to contribute to disaster prevention efforts."
Read more from The Japan News at https://japannews.yomiuri.co.jp/
