Samoa's Historic Contribution to Global Warming Since 1850
Key Insights
Overall Historic Contribution
Samoa's historic warming impact is around 50 megatonnes of CO2‑equivalent since 1850. On a global scale this is a negligible share. On a population basis, the long‑period average is around 3 tonnes per capita per year, which places Samoa in the moderate range. This reflects a small nation whose contribution is limited globally but still meaningful at home.
What Drove The Impact
Nearly two‑fifths of Samoa's impact comes from land use. Emissions grew into the mid‑20th century and then eased, with the late 1980s to early 1990s marking a shift toward years with net uptake; since then land use has often hovered around small negative values with occasional rebounds. Over a third stems from methane, mostly livestock with a smaller role for waste. Methane emissions rose steadily through the 1970s and 1980s, stayed relatively stable into the 2000s, and have edged down since the mid‑2010s; the associated warming impact has fallen faster as emissions eased. Fossil CO2, almost entirely oil use, remained very low for most of the historical record but increased from the late 1980s, reaching roughly a quarter of a megatonne per year in recent years. Nitrous oxide has been a minor, gradually rising source, and fluorinated gases remain tiny.
Priorities For Future Progress
With moderate historic per capita emissions and a tiny global share, Samoa's priority is to lock in a cleaner development path. Protect and enhance land‑use practices that sustain the recent net uptake. Keep methane moving downward by improving livestock management and solid‑waste handling. Curb oil‑based CO2 by boosting efficiency and shifting to cleaner energy where feasible. These steps target the dominant sources and help ensure Samoa's future contribution to warming stays low.
Background
Historic Per Capita Emissions
Historic per capita emissions are a crucial long-period (since 1850), population-weighted (accounting for changing population size) indicator. It shows the contribution of greenhouse gas emissions of a nation per capita per year to the current warming.
The rating scale is:
- Extremely High: above 10 tonnes per capita per year
- Very High: above 7.5 tonnes
- High: above 5 tonnes
- Moderate: above 2.5 tonnes
- Low: above 0 tonnes
- Negative Emissions: under 0
Historically, we don't expect any nation to reach negative emissions. Current warming, or warming targets, like 1.5 °C and 1.7 °C are all based on the fact that there have been human-induced greenhouse gas emissions and there will be some more. It is clear, however, that some nations have had incredibly high historic contributions per capita.
Total Historic Impact
This is the total amount of CO2, CH4, N2O, and F-Gases emissions of a nation from 1850 till 2023 (last available year in the data) expressed in megatonnes of CO2-equivalents. The gases have different atmospheric lifetimes (decay) and warming effects, for this reason we use the GWP100 (100 year time horizon method) to calculate the global warming potential of N2O and F-Gases to express in CO2-equivalents. For CH4, which is a short-term gas, we use the GWP* method to express the historic impact in CO2-equivalents.
Wikipedia: Global Warming PotentialTotal Historic Share
This is a nation's total historic share of global emissions and its contribution to global warming. It is an indicator of historic responsibility. All nations share the responsibility to ensure that developing nations do not copy and repeat the behavior of nations with high historic greenhouse gas emissions, they should not buy into old unsustainable fossil-fuels-based technology, land-use, and infrastructure, rather foster a sustainable and cleaner development.
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. Population data are also from Global Carbon Project where available, however, for many nations it doesn't have historic population going back to 1850. Those historic gaps are filled with population data from Our World in Data.
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.
Our World in Data Population - Our World in Data
Update cycle: YearlyDelay: 7 monthsCredits: HYDE (2023); Gapminder (2022); UN WPP (2024) – with major processing by Our World in Data