The Economics of 350

The report argues that stabilizing atmospheric CO2 at 350 ppm is economically feasible, with estimated costs ranging from 1% to 3% of global GDP per year. It challenges 'go slow' economic recommendations, specifically critiquing the DICE model's default assumptions, and suggests that the costs of inaction far outweigh the costs of rapid mitigation. The authors emphasize that achieving this target requires a comprehensive global transition to carbon-free energy and the implementation of negative emissions technologies, such as large-scale reforestation and biomass energy with carbon capture and storage (CCS).

• The estimated annual cost of a vigorous effort to rebuild the global economy around carbon-free technologies to meet stringent emissions goals is between 1% and 3% of world GDP.
• Scientific evidence, specifically from James Hansen, suggests that reducing atmospheric CO2 from 385 ppm to 350 ppm by 2100 is essential to prevent dangerous climate change, as climate sensitivity may be as high as 6°C—double the 3°C estimate 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 report's modification of the DICE model shows that if climate sensitivity is 6°C and economic damages are based on the fourth or fifth power of temperature increases, the model recommends rapid emissions elimination before mid-century to maximize human welfare.
• A review of U.S. policy costs indicates a divide between business-sponsored studies, which project catastrophic job and GDP losses, and independent modeling groups, which find that moderate emissions reductions would have negligible impacts on employment and income.
• Technological optimists, including McKinsey & Company, suggest that some emission reductions could have negative costs due to energy savings, particularly if oil prices are high (e.g., US$90 per barrel).
• The authors argue that carbon pricing through taxes or trading systems is superior to relying on market fossil fuel prices, as policy-driven prices incentivize conservation without encouraging destructive production like deep-sea drilling.

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} }