The GOSAT Series consists of the earth‐observing satellites GOSAT, GOSAT‐2, and GOSAT‐GW,
which observe greenhouse gases such as carbon dioxide and methane. The GOSAT Series is a project
that is jointly promoted by the three entities: the Ministry of the Environment (MOE), the National
Institute for Environmental Studies (NIES), and the Japan Aerospace Exploration Agency (JAXA).
Observing carbon dioxide
with GOSAT Series
Observation of carbon dioxide (CO2) with GOSAT Series
GOSAT‐GW, the third satellite in the Series after GOSAT and GOSAT‐2, is scheduled to be launched.
The GOSAT Series is aimed at helping with the development of climate change‐related science,
and contributing to climate‐change policies.
Global Observing SATellite for Greenhouse gases and Water cycle (GOSAT‐GW)
In Wide Mode, a 911 km‐wide area is
observed all at once, so there is 100
to 1,000 times more data than before.
Focus Mode has a high resolution
of 3 km (target resolution of 1 km),
so large‐scale emission sources
can be captured in detail.
Illustration of
Wide Mode
Through the simultaneous observation of CO2 and
nitrogen dioxide (NO2), human‐induced CO2 emission
sources can be identified, and emissions can be
accurately estimated.
Absorption & emission volumes
estimated using GOSAT‐GW
data (illustration)
Observation of NO2 with European
satellites
GOSAT‐GW will simultaneously
observe CO2.
Aiming for high‐precision observation
with greater detail
Aiming for high‐precision observation
with greater detailJan20092010201120122013201420152016201720182019202020212022Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Observation results from GOSAT (from June 2009 onward)
*Observation has been continuing even after August 2019.
©Copernicus Sentinel data 2022
The following are monthly averages of CO2 concentrations from the ground up to approximately 70 km in the sky (XCO2
concentrations) that have been observed with the GOSAT Series. The GOSAT Series ascertains CO2 concentrations by observing
sunlight reflected off of the surface of the ground. Even though there are some regions where observation is difficult, such as cloudy
areas, and polar areas with low solar elevation, the GOSAT Series is able to comprehensively observe the entire earth.
Observation results from GOSAT‐2 (from August 2019 onward)
Although simple comparisons cannot be made since the data from both GOSAT
and GOSAT‐2 have not yet been corrected for errors and so on, there appears
to be a trend in which concentrations have been rising in recent years.
GOSAT‐2 observes the entire earth in even greater detail than GOSAT, over a period of six
days. Moreover, it appears to have a higher quantity of valid observation data than
GOSAT. This is due the fact that it has been equipped with improved sensor functions, and
functions for observing while automatically avoiding clouds, which hinder observation.
Illustration of
Focus Mode
Image © JAXA / NIES / MOE
370 375 380 385 390 395 400 405 410 415 420 425 430 435XCO2[ppm]
GOSAT‐GW, the third satellite in the Series after GOSAT and GOSAT‐2, is scheduled to be launched.
GOSAT‐GW will implement the following missions.
Aims of GOSAT‐GW
The GOSAT Series will help improve the reliability and transparency of climate‐change policies that
countries implement based on the Paris Agreement, and contribute to the development of climate‐change science.
◎にじゅうまる Monitoring of greenhouse gases ◎にじゅうまる Verifying human‐induced greenhouse
gas emissions by country
Like GOSAT and GOSAT‐2, GOSAT‐GW will monitor fluctuations
in concentrations of greenhouse gases.
◎にじゅうまる Detecting large‐scale emission sources, etc.
GOSAT‐GW will aim to achieve a high level of accuracy
for estimations of emissions from large‐scale emission
sources, and detect as‐yet‐unknown emission sources.42041040039038020001950190018501800175017002013CO2 CH4
2009 2010 2011 2012 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025
GOSAT‐GW will aim to improve accuracy, transparency,
and reliability regarding the CO2 and CH4 emissions that
countries announce based on the Paris Agreement.
Comparative verification will
be carried out with the aim
of improving the reliability of
emission reports.
A b s o r p t i o n & e m i s s i o n
volumes estimated using
GOSAT‐GW data (illustration)
Emission reports of
countries
Detection of
as‐yet‐unknown
emission sources
Observation of
large‐scale emission
sources
What will concentrations of greenhouse gases be in the future?20092010201120122013201420152016201720182019202020212022
Observing methane
with GOSAT Series
The GOSAT Series consists of the earth‐observing satellites GOSAT, GOSAT‐2, and GOSAT‐GW, which
observe the greenhouse gases such as carbon dioxide and methane. The GOSAT Series is a project
that is jointly promoted by the three entities: the Ministry of the Environment (MOE), the National
Institute for Environmental Studies (NIES), and the Japan Aerospace Exploration Agency (JAXA).
Observation of methane (CH4) with GOSAT Series
The following are monthly averages of CH4 concentrations from the ground up to approximately 70 km in the sky (XCH4
concentrations) that have been observed with the GOSAT Series. The GOSAT Series ascertains CH4 concentrations by observing
sunlight reflected off of the surface of the ground. Even though there are some regions where observation is difficult, such as cloudy
areas, and polar areas with low solar elevation, the GOSAT Series is able to comprehensively observe the entire earth.
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
GOSAT‐2 observes the entire earth in even greater detail than GOSAT, over a period of six
days. Moreover, it appears to have a higher quantity of valid observation data than
GOSAT. This is due the fact that it has been equipped with improved sensor functions, and
functions for observing while automatically avoiding clouds, which hinder observation.
Observation results from GOSAT‐2 (from August 2019 onward)
Observation results from GOSAT (from June 2009 onward)
*Observation has been continuing even after August 2019.
Image © JAXA / NIES / MOE
1.60 1.65 1.70 1.75 1.80 1.85 1.90 1.95 2.00 2.05XCH4[ppm]