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If the burning of all fossil fuels stopped today, it is likely that global temperatures would remain the same and could potentially continue to rise.

Summary​

Stopping fossil fuel combustion would not immediately halt global warming due to existing atmospheric CO₂ persistence. Current models suggest temperatures could stabilize or slightly decrease (-0.36°C to +0.29°C range) over 50 years after immediate cessation. However, reduced sulfur aerosols from fuel burning might trigger a termination shock, potentially raising temperatures by removing their cooling effect (-1.5°C offset). Climate models are known to struggle to fully account for aerosol impacts and tipping points like ice sheet collapse. The complex interplay between greenhouse gas retention, aerosol reduction, and Earth system feedbacks means temperature trajectories remain uncertain even with emissions cessation.

Global warming is driven by greenhouse gases in the atmosphere, primarily carbon dioxide (CO₂), methane (CH₄), and nitrous oxide (N₂O) from the combustion of fossil fuels. Between 1850 and 2020, a cumulative 2.42 trillion tons of CO₂ have been released into the atmosphere by humans, and 2022 alone saw an estimated 40.5 billion tons released 1. Much of this CO₂ remains in the atmosphere for decades and even centuries, as the Earth is unable to absorb all the carbon dioxide being produced. As a result, the remaining carbon dioxide in the atmosphere will continue to have a greenhouse effect after the burning of fossil fuels stops.

A metric for calculating how global temperatures will change when the burning of fossil fuels has stopped is the 'Zero Emissions Commitment (ZEC),' which is a measure of global mean temperatures 50 years after the cessation of CO₂ emissions. Extensive climate modeling using an ensemble of different climate models estimates the range of ZEC 50 years after the cessation of CO₂ emissions to be between -0.36°C – +0.29°C, with a mean of -0.07°C 2.

One factor that further complicates the calculation of the ZEC is how anthropogenic sulfate aerosols are treated. Aerosols are released into the atmosphere via a number of sources, including the burning of fossil fuels, which contain sulfur. Since 2010, global aerosol emissions have been decreasing due to regulations on sulfur dioxide (SO₂) emissions from burning fossil fuels 3, primarily caused by the recent International Maritime Organization regulation to reduce sulfur content in shipping fuels. The climate models used to estimate the ZEC primarily focus on the emissions of CO₂ and do not adequately account for the impact of aerosols 2 3. The cooling effect of aerosols cannot be overstated. Global climate forcing from greenhouse gases is estimated to be around +4 W/m² while the forcing from aerosols is -1 W/m², meaning that the current thermal forcing from aerosols on global temperatures is as much as -1.5°C 3. Therefore, the immediate cessation of fossil fuels could effectively cause a 'termination shock' where the cooling effect of aerosols is removed abruptly, causing a rapid increase in global temperatures.

It should also be noted that all of these estimations do not account for any tipping point scenarios such as the differences of antarctic ice that may still occur even as the burning of fossil fuels stops.

Sources​

Footnotes​

  1. Friedlingstein, P., O'Sullivan, M., Jones, M. W., Andrew, R. M., Hauck, J., Olsen, A., Peters, G. P., Peters, W., Pongratz, J., Sitch, S., Le Quéré, C., Canadell, J. G., Ciais, P., Jackson, R. B., Alin, S., Aragão, L. E. O. C., Arneth, A., Arora, V., Bates, N. R., Becker, M., Benoit-Cattin, A., Bittig, H. C., Bopp, L., Bultan, S., Chandra, N., Chevallier, F., Chini, L. P., Evans, W., Florentie, L., Forster, P. M., Gasser, T., Gehlen, M., Gilfillan, D., Gkritzalis, T., Gregor, L., Gruber, N., Harris, I., Hartung, K., Haverd, V., Houghton, R. A., Ilyina, T., Jain, A. K., Joetzjer, E., Kadono, K., Kato, E., Kitidis, V., Korsbakken, J. I., Landschützer, P., Lefèvre, N., Lenton, A., Lienert, S., Liu, Z., Lombardozzi, D., Marland, G., Metzl, N., Munro, D. R., Nabel, J. E. M. S., Nakaoka, S.-I., Niwa, Y., O'Brien, K., Ono, T., Palmer, P. I., Pierrot, D., Poulter, B., Resplandy, L., Robertson, E., Rödenbeck, C., Schwinger, J., Séférian, R., Skjelvan, I., Smith, A. J. P., Sutton, A. J., Tanhua, T., Tans, P. P., Tian, H., Tilbrook, B., van der Werf, G., Vuichard, N., Walker, A. P., Wanninkhof, R., Watson, A. J., Willis, D., Wiltshire, A. J., Yuan, W., Yue, X., & Zaehle, S. (2020). Global carbon budget 2020. Earth System Science Data, 12(4), 3269–3340. https://doi.org/10.5194/essd-12-3269-2020 ↩

  2. MacDougall, A. H., Frölicher, T. L., Jones, C. D., Rogelj, J., Matthews, H. D., Zickfeld, K., Arora, V. K., Barrett, N. J., Brovkin, V., Burger, F. A., Eby, M., Eliseev, A. V., Hajima, T., Holden, P. B., Jeltsch-Thömmes, A., Koven, C., Mengis, N., Menviel, L., Michou, M., Mokhov, I. I., Oka, A., Schwinger, J., Séférian, R., Shaffer, G., Sokolov, A., Tachiiri, K., Tjiputra, J., Wiltshire, A., & Ziehn, T. (2020). Is there warming in the pipeline? A multi-model analysis of the Zero Emissions Commitment from CO₂. Biogeosciences, 17(11), 2987–3016. https://doi.org/10.5194/bg-17-2987-2020 ↩ ↩2

  3. Hansen, J. E., Sato, M., Simons, L., Nazarenko, L. S., Sangha, I., Kharecha, P., Zachos, J. C., von Schuckmann, K., Loeb, N. G., Osman, M. B., Jin, Q., Tselioudis, G., Jeong, E., Lacis, A., Ruedy, R., Russell, G., Cao, J., & Li, J. (2023). Global warming in the pipeline. Oxford Open Climate Change, 3(1), Article kgad008. https://doi.org/10.1093/oxfclm/kgad008 ↩ ↩2 ↩3