Beyond the social cost of carbon: Negative emission technologies as a means for biophysically setting the price of carbon.

The social cost of carbon (SCC) is an estimate of the costs that society will incur because of the emission of one tonne of CO2. Because of the large uncertainties in the effects of climate change and the subjectivity of the discount rate, estimates of SCC range widely, from - 10.2 to 105 213$ t-1 in 2010 USD. Despite this range, the SCC has been used or proposed as a basis for a wide variety of policymaking including cost-benefit analysis and carbon taxes. The SCC suffers from several practical and philosophical weaknesses: it is anthropocentric, it neglects the acidification of oceans, it assumes that quantifiable economic variables like GDP are the primary costs that humans will experience from climate change, and it is impossible to quantify objectively. Further, the ethical implications of a carbon pricing policy include both the value of the carbon price, and the use of revenues generated by the policy. Thus, revenue neutral carbon policies as in some SCC-based proposals, are unlikely to be just. Here, we propose that the cost of emerging negative-emission technologies would be an alternative means for setting a carbon price and avoid these philosophical and practical weaknesses.