Japan's Yearly Greenhouse Gas Emissions in CO₂ Equivalent
Key Insights
A Century Of Growth
Japan's emissions story is dominated by CO2 from fossil fuels. After modest levels through the early 20th century, a rapid surge during the 1960s lifted CO2 to around 1,300 megatonnes by the mid-2000s. Since then, emissions have declined to just under 1,000 megatonnes, yet they still account for well over four-fifths of the country's historic warming impact. Land-use emissions shifted from a source to a small net sink from the 1960s onward, though that sink has weakened toward near zero in recent years.
Other Gases In Perspective
Methane climbed steadily to around 80 megatonnes by 1970, then fell to around 30 today; its warming impact dropped markedly as emissions declined, with slower improvements more recently. Nitrous oxide rose to around 40 by the mid-1990s and has since fallen to around 20. Fluorinated gases grew rapidly late in the 20th century to around 60, then declined to around 30 in the 2020s.
Current Trajectory And Priorities
Among the major fossil sources, oil has been trending down since the 1990s to around 350 megatonnes, coal remains high but has fallen since the mid-2010s toward nearly 400, and gas has eased from around 250 to around 200 since the mid-2010s. The overall trajectory is downward, but sustaining and accelerating cuts-especially in coal and oil-will be decisive for continued national reductions, while maintaining momentum on gas can lock in further gains.
Background
Greenhouse gas emissions from human activities are the main drivers of human-induced warming. In the scientific literature, human-induced emissions are often referred to as anthropogenic emissions.
- CO2 Fossil Fuels and Industry (CO2 FFI)
- CO2 Land-Use, Land-Use Change and Forestry (CO2 LULUCF)
- Methane (CH4)
- Nitrous oxide (N2O)
- Fluorinated gases (F-gases)
Emissions from all different gases are expressed in CO2-equivalent units to make it possible to compare the relative emissions from these different gases. CO2-equivalents are calculated using the global warming potentials of the respective gases, in this case using a 100-year time horizon.
Wikipedia: Global Warming PotentialTotal Historic Share
Emissions from all different gases are expressed in CO2-equivalent units to make it possible to compare the relative emissions from these different gases. CO2-equivalents are calculated using the global warming potentials of the respective gases, in this case using a 100-year time horizon.
CO2 From Fossil Fuels and Industry
The sources are mostly fossil-fuel combustion emissions from coal, oil, and gas, as well as emissions from industrial processes such as cement production. Cement also absorbs CO2 out of the atmosphere through carbonation, which reduces emissions by about 0.8 Gt per year and is included here.
CO2 From Land-Use, Land-Use Change, and Forestry
The main driver of these emissions is deforestation, which includes logging and forest degradation, as well as other land-use change activities. The emissions also take into account the absorption of CO2 by processes that remove CO2 from the atmosphere, such as afforestation and reforestation. It is the net effect that is indicated here.
Methane (CH4)
Methane emissions are caused by human activities such as rearing livestock, agricultural practices, and fugitive fossil fuel emissions.
Nitrous Oxide (N2O)
Common sources of these emissions are fossil fuel emissions and the agricultural use of synthetic fertilizer and manure.
Fluorinated Gases (F-gases)
Fluorinated gases are a group of gases defined by UNFCCC: hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), sulfur hexafluoride (SF6), and nitrogen trifluoride (NF3). Fluorinated gases are also known as halogenated gases.
Wikipedia: Greenhouse Gas EmissionsIPCC: Annual Report 6, 5.2.1 5.2 Historical Trends, Variability and Budgets of CO2, CH4 and N2O
Units and Measures
CO2-equivalent emissions are expressed in the total weight in megatonnes per year. 1 Megatonne is equal to 1 million tonnes.
Wikipedia: MegatonneWikipedia: Global warming potential
About the Data
The last available year in all the emission datasets is 2023. CO2 emissions data is from the Global Carbon Project. It contains national CO2 emissions from fossil sources and land-use change. Emissions from CH4, N2O and F-gases come from the PRIMAP-Hist dataset. It is a rich dataset that combines several published sources to create a historical emissions time series for various greenhouse gases.
The Key Insights paragraph was created using a large language model (LLM) in combination with our data, historic events, and a structured approach for best accuracy by separating the context generation from the interpretation and narrative.
Data Sources
Global Carbon Budget 2024 Global Carbon Budget
Update cycle: yearlyDelay: ~ 10 months after the end of the year. Current year values are estimated and published in November.Credits: Friedlingstein et al., 2024, ESSD. Friedlingstein, P., O'Sullivan, M., Jones, M. W., Andrew, R. M., Hauck, J., Landschützer, P., Le Quéré, C., Li, H., Luijkx, I. T., Olsen, A., Peters, G. P., Peters, W., Pongratz, J., Schwingshackl, C., Sitch, S., Canadell, J. G., Ciais, P., Jackson, R. B., Alin, S. R., Arneth, A., Arora, V., Bates, N. R., Becker, M., Bellouin, N., Berghoff, C. F., Bittig, H. C., Bopp, L., Cadule, P., Campbell, K., Chamberlain, M. A., Chandra, N., Chevallier, F., Chini, L. P., Colligan, T., Decayeux, J., Djeutchouang, L., Dou, X., Duran Rojas, C., Enyo, K., Evans, W., Fay, A., Feely, R. A., Ford, D. J., Foster, A., Gasser, T., Gehlen, M., Gkritzalis, T., Grassi, G., Gregor, L., Gruber, N., Gürses, Ö., Harris, I., Hefner, M., Heinke, J., Hurtt, G. C., Iida, Y., Ilyina, T., Jacobson, A. R., Jain, A., Jarníková, T., Jersild, A., Jiang, F., Jin, Z., Kato, E., Keeling, R. F., Klein Goldewijk, K., Knauer, J., Korsbakken, J. I., Lauvset, S. K., Lefèvre, N., Liu, Z., Liu, J., Ma, L., Maksyutov, S., Marland, G., Mayot, N., McGuire, P., Metzl, N., Monacci, N. M., Morgan, E. J., Nakaoka, S.-I., Neill, C., Niwa, Y., Nützel, T., Olivier, L., Ono, T., Palmer, P. I., Pierrot, D., Qin, Z., Resplandy, L., Roobaert, A., Rosan, T. M., Rödenbeck, C., Schwinger, J., Smallman, T. L., Smith, S., Sospedra-Alfonso, R., Steinhoff, T., Sun, Q., Sutton, A. J., Séférian, R., Takao, S., Tatebe, H., Tian, H., Tilbrook, B., Torres, O., Tourigny, E., Tsujino, H., Tubiello, F., van der Werf, G., Wanninkhof, R., Wang, X., Yang, D., Yang, X., Yu, Z., Yuan, W., Yue, X., Zaehle, S., Zeng, N., and Zeng, J.: Global Carbon Budget 2024, Earth Syst. Sci. Data Discuss. [preprint], https://doi.org/10.5194/essd-2024-519, in review, 2024.
PRIMAP-hist The PRIMAP-hist national historical emissions time series (1750-2023)
Update cycle: Every few monthsDelay: Less than 1 yearCredits: Gütschow, Johannes; Busch, Daniel; Pflüger, Mika (2024): The PRIMAP-hist national historical emissions time series (1750-2023) v2.6. Zenodo.