The Economics of 350

The report argues that stabilizing atmospheric CO2 at 350 ppm is economically feasible, with estimated costs between 1% and 3% of global GDP, and is necessary to avoid catastrophic climate change. It challenges the 'go slow' approach of some economists and demonstrates that with adjusted assumptions on climate sensitivity and economic damages, even standard models like DICE support rapid decarbonization.

• The estimated annual cost of a vigorous effort to rebuild the global economy around carbon-free technologies to meet stringent emissions goals is between one and three percent of world GDP.
• James Hansen argues that reducing atmospheric CO2 from 385 ppm to 350 ppm by 2100 is essential to avoid dangerous anthropogenic climate change, based on evidence suggesting a climate sensitivity of 6°C, which is approximately double the 3°C projected in the IPCC's Fourth Assessment Report (AR4).
• Achieving a 350 ppm target by 2100 requires achieving net negative emissions, which can be pursued through reforestation, biochar, and biomass energy combined with carbon capture and storage (CCS).
• The authors argue that relying on market prices for fossil fuels to reduce emissions is a mistake because high prices enrich fossil fuel owners and incentivize destructive production; instead, they recommend a carbon price through a tax or trading system.
• Some optimistic studies, such as those by McKinsey, Greenpeace, and the Union of Concerned Scientists, suggest that rapid abatement could save money overall due to fuel savings, though these findings are sensitive to high projected oil prices.
• The report notes that military spending exceeds 2.5 percent of GDP in 68 countries, including the United States and China (where it exceeds 4 percent), suggesting that the global economy can afford a similar expenditure for climate protection.

APA

Ackerman, F., Stanton, E. A., DeCanio, S. J., Goodstein, E., Howarth, R. B., Norgaard, R. B., Norman, C. S., & Sheeran, K. A. (2009). The Economics of 350. Stockholm Environment Institute. https://www.sei.org/mediamanager/documents/Publications/Climate-mitigation-adaptation/Economics_of_climate_policy/Economics-of-350-Final.pdf

Chicago

Ackerman, Frank, Elizabeth A. Stanton, Stephen J. DeCanio, Eban Goodstein, Richard B. Howarth, Richard B. Norgaard, Catherine S. Norman, and Kristen A. Sheeran. The Economics of 350. Stockholm Environment Institute, 2009. https://www.sei.org/mediamanager/documents/Publications/Climate-mitigation-adaptation/Economics_of_climate_policy/Economics-of-350-Final.pdf.

Wikipedia

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BibTeX

@techreport{ackerman2009economics, author = {Ackerman, Frank and Stanton, Elizabeth A. and DeCanio, Stephen J. and Goodstein, Eban and Howarth, Richard B. and Norgaard, Richard B. and Norman, Catherine S. and Sheeran, Kristen A.}, title = {{The Economics of 350}}, institution = {Stockholm Environment Institute}, year = {2009}, month = oct, url = {https://www.sei.org/mediamanager/documents/Publications/Climate-mitigation-adaptation/Economics_of_climate_policy/Economics-of-350-Final.pdf}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }