New Zealand's Yearly Greenhouse Gas Emissions in CO₂ Equivalent
Key Insights
A Century Of Land Change
Land-use change has been one of New Zealand's defining climate drivers, contributing about a third of the country's historic warming impact. Emissions rose through the late 19th and early 20th centuries with extensive landscape conversion, peaked around the mid-20th century, then declined steadily. Since the late 20th century they have hovered near zero, with some years even tipping into net absorption of CO2.
Fossil CO2’s Post-War Surge
Fossil and industry CO2 grew gradually before the war, accelerated from the 1940s and again through the 1980s to early 2000s, and has edged down since the mid-2000s. Oil-related emissions make up almost half of fossil CO2, while coal is around a third; coal has generally fallen since the mid-2000s. Overall, fossil CO2 represents roughly a fifth of New Zealand's historic contribution.
Methane Plateaus, Impact Eases
Methane is the single largest contributor, roughly a third of the warming impact, driven overwhelmingly by livestock. Emissions climbed rapidly to the early 1970s, then stayed high but fairly stable for decades, with a gentle decline since the mid-2010s. As emissions leveled off, the warming impact from methane declined sharply, particularly in recent years.
Agriculture Drives Nitrous Oxide
Nitrous oxide rose through the mid-20th century alongside agricultural intensification and has been broadly stable since the early 1970s. Almost all N2O comes from agriculture, making it a material share of New Zealand's historic impact.
What Matters Now
Today, fossil CO2 is slowly declining (coal down, oil still high), methane is easing from a long plateau, N2O is mostly flat, and land-use emissions are near zero with occasional net uptake. Progress hinges on sustaining land carbon gains, accelerating cuts in oil-dominated fossil CO2, and delivering steady reductions in agricultural methane and nitrous oxide.
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.