These sensor packages are designed for deployment from passing aircraft and offer critical early warnings of hazardous weather conditions.
Scientists from Nagoya University, the National Research Institute for Earth Science and Disaster Resilience, Kyoto University’s Disaster Prevention Research Institute, and Meisei Electric Co. have developed a sensor system to track typhoons. The “dropsonde” sensor, called iMDS-17, eliminates the need for a parachute, offering a lightweight and efficient solution for atmospheric monitoring.
First introduced in 2017, the iMDS-17 weighs approximately 130g, enabling it to descend without parachutes while accurately measuring atmospheric conditions throughout the troposphere. Drawing on technology from the Japan Meteorological Agency’s radiosonde (iMS-100), the iMDS-17 integrates a direct pressure sensor for precise measurements.
The dropsonde is designed to monitor atmospheric conditions such as temperature, pressure, and humidity within typhoons. This data aids in predicting a storm’s intensity and trajectory, offering crucial early warnings to minimize potential damage. In testing, the team compared the iMDS-17 to traditional radiosondes, finding the new system delivered comparable accuracy, though they acknowledged room for improvement in humidity readings.
In t trial, researchers deployed 50 dropsondes into Typhoon Barijat using a traditional aircraft-drop method. “On October 9, 2024, we observed atmospheric conditions in the storm’s genesis phase near its center,” said co-author Kazuhisha Tsuboki. The data collected was distributed globally via the World Meteorological Organization’s Global Telecommunication System (GTS) to enhance weather forecasting models. Following pre-verification of humidity data, notable improvements were achieved, and the team plans additional aircraft-based observations in 2025.
The iMDS-17 operates similarly to radiosondes used with weather balloons, but instead of ascending, it is designed to be dropped from aircraft at altitudes around 43,000 feet, traveling at 450 mph. To broaden its application, the team is also testing a balloon-borne “dropsonde shooter” system for deploying the sensors.