Researchers achieve high accuracy with innovative dropsonde for typhoon observation

Researchers achieve high accuracy with innovative dropsonde for typhoon observation
by Riko Seibo
Tokyo, Japan (SPX) Dec 18, 2024

Researchers at Nagoya University, in collaboration with Meisei Electric Co. and the National Research Institute for Earth Science and Disaster Resilience, have demonstrated the high performance of their newly developed typhoon dropsonde, a compact observation device designed to descend without a parachute. This advanced tool enhances the collection of critical atmospheric data for accurate typhoon tracking and forecasting.

The dropsonde, known as iMDS-17, is a lightweight, 130-gram instrument constructed primarily from biodegradable materials. Equipped with a fin, the device descends steadily when released from an aircraft, eliminating the need for a parachute - a significant improvement over conventional dropsondes. As it falls, iMDS-17 measures temperature, humidity, and wind speed, providing vital vertical atmospheric profiles within typhoons.

To ensure its accuracy, the team conducted a comparative study using a reference radiosonde approved by the Japan Meteorological Agency. Both instruments were attached to a single balloon and simultaneously released at an altitude of 12 kilometers over Okinawa on March 27 and 28, 2024. Differences between the devices' measurements were minimal, with temperature variances below 1 K and wind data discrepancies under 2 m/sec across altitudes ranging from 9 km to 2 km. Humidity readings, while showing some dryness compared to the radiosonde, marked an area for further improvement.

The dropsonde underwent further evaluation in real storm conditions on October 9 and 10, 2024, when Designated Associate Professor Sachie Kanada and Professor Kazuhisa Tsuboki from Nagoya University's Institute for Space and Earth Environmental Research deployed 50 dropsondes into the eye of Typhoon Barijat.

"On October 9, we had just arrived around the storm center in the typhoon genesis phase," Kanada said. "The observed profiles of atmospheric conditions for the midlatitude typhoon were delivered worldwide via the Global Telecommunication System (GTS) of the WMO and used for the weather forecasting systems. This time, we preverified humidity data of the dropsondes and the data was improved. Using this dropsonde, we are planning to have another aircraft observation in 2025."

The development and successful deployment of the iMDS-17 mark a significant step forward in typhoon observation technology, addressing prior limitations in ocean-based atmospheric monitoring and enhancing global weather prediction capabilities.

Research Report:Evaluation of newly developed dropsonde for aircraft observation