Japan Satellite for Analyzing Greenhouse Gases Expected to Contribute Greatly to Global Warming Countermeasures; Trump Stance Stifling Competition

By Tomoko Kito / Yomiuri Shimbun Staff Writer

10:42 JST, August 10, 2025

A new Japanese satellite for measuring greenhouse gases, which was launched in June, is expected to contribute greatly to measures to ease global warming.

The satellite, which was jointly developed by the Environment Ministry, the National Institute for Environmental Studies and other partners, is called the Global Observing SATellite for Greenhouse gases and Water cycle (GOSAT-GW), otherwise known by its nickname Ibuki GW. It can collect significantly more information than similar Japanese satellites.

Past satellites that had the same purpose could only make observations at points about 200 kilometers apart. They were therefore limited to analyzing data on a country-by-country basis. Ibuki GW, on the other hand, has sensors that can observe greenhouse gases in 900-kilometer-wide belt zones, making it possible to obtain greenhouse gas data from the entire surface of Earth within three days and to analyze it at a city-by-city level.

The satellite can observe nitrogen dioxide, a pollutant gas, in the air and estimate emission volumes with high accuracy based on the form of smoke discharged from thermal power plants and other data.

Ibuki GW was launched in the early hours of June 29 and began communicating from orbit at an altitude of about 670 kilometers. It is expected to start transmitting data to international organizations by the end of this year.

“We will provide estimate results and other data to Asian countries and private companies,” said an official of the Environment Ministry at an international academic conference of satellite observations held in Takamatsu in June. “To contribute to creating transparency with the data, we will verify emission reports that countries submit to the United Nations.”

Among the topics discussed by the attendees at the conference were the moves of the administration of U.S. President Donald Trump, who has a negative stance when it comes to measures for dealing with global warming. Although Japan and the United States had been improving their observation technologies in a spirit of competition in the field, many U.S. researchers were absent from the conference this time.

A senior NASA official said that budget cuts had meant that its young researchers could not obtain permission to travel to Japan to attend the conference. According to the U.S. budget bill for the 2026 fiscal year, which NASA disclosed, the funding allocated to two U.S. satellites dedicated to observing greenhouse gases was “zero.”

“There can be neither studies nor measures utilizing the data without competition and mutual assistance with the United States,” said Akihiko Kuze, a former official of the Japan Aerospace Exploration Agency (JAXA) and former project manager for Ibuki GW’s predecessor.

With emission volumes of greenhouse gases on the rise, the United States and other countries have been struck one after another by disastrous wildfires and torrential rains this year.

Understanding conditions in areas throughout the world, including polar regions and oceans, is essential for developing countermeasures.