Trends of measured climate forcing agents
Abstract
The growth rate of climate forcing by measured greenhouse gases peaked near 1980 at almost 5 W/m2 per century. This growth rate has since declined to ≈3 W/m2 per century, largely because of cooperative international actions. We argue that trends can be reduced to the level needed for the moderate "alternative" climate scenario (≈2 W/m2 per century for the next 50 years) by means of concerted actions that have other benefits, but the forcing reductions are not automatic "co-benefits" of actions that slow CO2 emissions. Current trends of climate forcings by aerosols remain very uncertain. Nevertheless, practical constraints on changes in emission levels suggest that global warming at a rate +0.15 ± 0.05°C per decade will occur over the next several decades.
- Publication:
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Proceedings of the National Academy of Science
- Pub Date:
- December 2001
- DOI:
- 10.1073/pnas.261553698
- Bibcode:
- 2001PNAS...9814778H
- Keywords:
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- Geophysics