In a first for Japanese researchers, a team led by professor Kazuhisa Tsuboki from the Institute for Space-Earth Environmental Research at Nagoya University will use aircraft to observe supertyphoons directly. Supertyphoons have become a growing problem in recent years due to global warming.
The 55-year-old professor hopes the team’s work will contribute to increasing the accuracy of typhoon forecasting in terms of direction and speed, among other factors, giving people ample time to prepare and evacuate.
The team recently held a trial run over the Noto Peninsula in Ishikawa Prefecture and is scheduled to conduct observations during the typhoon season between August and October.
The U.S. military started using aircraft to observe tropical cyclones around Japan after the end of World War II and shared the data. This continued until 1987, when rising costs and advances in satellite observation technology brought such operations to an end.
However, the amount of data that can be obtained from satellites is limited, and the accuracy declines as a typhoon grows in scale and intensity.
Recently, the number of typhoons reaching Japan without losing their high velocity has increased due to rising sea temperatures caused by global warming, so there is a need to improve the accuracy of observations.
Tsuboki’s research team plans to rent a private aircraft and fly it a few dozen kilometers above a typhoon before dropping approximately 20 dropsondes into its eye.
A dropsonde is a disposable, 30-cm-long cylindrical device that collects data on temperatures, air pressure, wind speeds and other characteristics of a typhoon.
Data from the dropsondes are entered into a simulation model developed by the team to analyze the scale, intensity and direction of the typhoon.
In the recent trial run, the team experimented with ejecting the dropsondes from the plane.
The actual observation is scheduled to be conducted at the south coast of Okinawa Island, where the team will wait for a relatively large typhoon to develop before starting.
“With the current typhoon forecast, there’s a limit to how much information we can get in terms of intensity and direction, so we are likely to sustain heavy damage from a supertyphoon,” said Tsuboki. “If we can predict typhoons accurately using aircraft observations, we can make sure that the people evacuate safely.”
Supertyphoons are defined as having a wind speed of 67 meters per second or greater, which can destroy buildings, blow away vehicles and cause heavy damage with torrential rain and storm surges.
More than 7,000 people were killed or declared missing after supertyphoon Haiyan hit the Philippines in 2013.
This section, appearing Tuesdays, features topics and issues from the Chubu region covered by the Chunichi Shimbun. The original article was published July 19.