World's first automated greenhouse gas observation of Earth's "surface" from inside passenger aircraft by ANA and others

ANA Holdings Inc. and other organizations have announced the start of demonstration testing for the automated observation of atmospheric components such as greenhouse gases from inside passenger aircraft. When installed on All Nippon Airways Group domestic flights, this system will enable comprehensive observation across the Japanese archipelago. While there are already examples of "line" observations using methods that directly take in air along flight routes, this system is characterized by observation of the "surface" of Earth using remote sensing. This is said to be a world first for regular passenger flights.

Since 2020, the company has been conducting joint research with the Japan Aerospace Exploration Agency (JAXA) on technology for observing atmospheric components from inside passenger aircraft under the name "GOBLEU." Their system applies principles from the Greenhouse gases Observing SATellite "IBUKI" (GOSAT) and detects light attenuation caused by greenhouse gas absorption. Observations are made through windows from inside the cabin; in the past, equipment had to be brought in for each observation and passenger seats had to be used.

In November last year, one Boeing 737 aircraft was newly modified to enable automated observation from a position invisible to passengers. Another aircraft is scheduled for modification in March this year, with plans to increase the number of modified aircraft according to demand. A patent application has been filed for this proprietary method.

IBUKI and similar satellites orbit at an altitude of approximately 600 kilometers from north to south, capturing wide areas and observing the same location on the Earth's surface every three days. In contrast, passenger aircraft fly at altitudes of about 10 kilometers, operating about four flights per day per aircraft. Since each route connects cities, frequent and detailed observation of the atmosphere over each city is possible. By utilizing the characteristics of both satellites and passenger aircraft together, the project aims to build a high-precision observation network. It will provide data useful for examining greenhouse gas emission reduction measures in urban areas and evaluating their effects.

"CONTRAIL," which has been undertaken by Japan Airlines, the Meteorological Research Institute of the Japan Meteorological Agency, and others since 1993, has been leading the way in atmospheric observation using passenger aircraft. There are also examples led by Europe with participation from Lufthansa German Airlines and others. All of these use methods that directly intake outside air, so observations are limited to flight routes in the upper atmosphere, but they are said to be useful for global warming predictions and other purposes.

In contrast, GOBLEU performs surface observations covering a width of 50 kilometers on the ground, diagonally below to the left of the aircraft's direction of travel. It captures carbon dioxide, nitrogen dioxide, and other gases, enabling detailed understanding of emission amounts in various locations and absorption amounts by forests. The spatial resolution is 100 meters near the aircraft and several kilometers in distant areas. The project also aims to sell observation data to companies.

At a press conference on December 16 last year, Ayako Matsumoto of the Business Development Department at ANA Holdings Inc. explained, "Direct sampling of upper atmosphere air (such as by CONTRAIL) is useful for simulations. GOBLEU's initiative acquires different types of data, and both are important." Mission Manager Hiroshi Suto at JAXA's Satellite Applications and Operations Center, stated, "They can complement each other. For example, by comparing or combining results from remote sensing and direct observation, knowledge will further increase."