🇲🇬 Madagascar's Historic Contribution to Global Warming Since 1850

Madagascar's Historic Contribution to Global Warming Since 1850

Key Insights

High Per Capita Impact

Madagascar's warming impact from historic emissions is roughly 9,100 megatonnes. While this represents only around a quarter of a percent of the global total, the historic per capita impact is just over 7 tonnes per capita per year-rated High. In short, the country's overall share is small, but the average long-run contribution per person is substantial.

Land Use Drives History

Around two-thirds of Madagascar's historic impact comes from land-use CO2. Emissions rose from modest levels in the early 20th century to much higher levels by the late 1950s, dipped in the mid-1960s, then climbed again, peaking at roughly 150 megatonnes by the late 1990s. Since the turn of the century they have trended down, falling to around a few dozen megatonnes in recent years. This long arc shows large swings, with recent decades moving in a more favorable direction.

Methane Trends From Agriculture

Methane accounts for about a quarter of the impact, led by livestock and crop production. Emissions built steadily through the mid-20th century, then grew more slowly from the late 1960s to early 2000s before rising again after the early 2000s. During the long plateau, the warming impact from methane declined, but it has increased again with renewed growth in recent years.

Other Gases, Smaller Roles

Nitrous oxide contributes around 7%, largely from agriculture, with a post-war jump and relatively steady levels since the 1990s. Fossil-fuel CO2 remains just over 1% of the total-low in historic terms-though it has been rising since around 2010. Fluorinated gases add a negligible share, increasing gradually since the mid-1990s from near zero.

Action Priorities For Madagascar

Given the High per capita rating, leadership in reducing land-use emissions is paramount-protecting and restoring ecosystems and improving land management-while curbing methane growth in livestock and crop production. Progress in these dominant sources can anchor a cleaner development path, with Madagascar also positioned to share successful approaches with others.

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 Potential

Total 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

Madagascar's Historic Contribution to Global Warming Since 1850