JAXA Begins New Rain Forecasting Satellite Development; Hopes for Enhanced Prediction of Typhoon Paths, Intensity

The Yomiuri Shimbun

1:00 JST, October 24, 2023

The Japan Aerospace Exploration Agency (JAXA) has initiated the development of a new Precipitation Radar satellite with the goal of enhancing the accuracy of heavy rain and flood forecasts by accurately measuring rain and snowfall from space using radio waves. The radar system it will carry boasts world-class capabilities, including the ability to measure the speed of falling raindrops. The satellite is scheduled for launch by the end of fiscal 2028.

Currently, the “Global Precipitation Measurement (GPM) core observatory,” launched in 2014 through collaboration among Japan, the United States and others, is in operation. The new satellite will not only be capable of measuring the speed of falling raindrops but will also have more than double the sensitivity of its predecessors, enabling it to detect even light rainfall. This improved capability will allow for more accurate measurements of precipitation over the seas south of Japan, leading to enhanced predictions of typhoon paths and intensity.

In addition, JAXA has been publishing “precipitation maps” based on satellite data, including data from GPM. These maps categorize global precipitation on an hourly basis and are used in over 140 countries for flood forecasting and monitoring of extreme weather events. With the addition of data from the new satellite, the resolution of these precipitation maps will significantly increase, making it possible to predict floods in smaller rivers.

The new satellite will weigh a maximum of 2.7 tons, with a total development cost of ¥39.4 billion. Development officially began this summer.

A JAXA representative said, “With the intensification of heavy rain-induced disasters worldwide due to climate change, we hope that the new satellite will contribute to reducing the damage.”