Early on in its tenure, the Obama Administration created a measure to quantify the costs of carbon emissions, known as the "Social Cost of Carbon" (SCC). This standard allowed agencies to calculate the benefit of policies that reduced CO2 emissions.
The impacts of climate change are wide-ranging - rising sea levels, increased droughts, higher frequency of mosquito-borne illnesses and so on - and the SCC aimed to capture all of those impacts. After extensive analysis, the government determined that the SCC is currently about $40 for each emitted ton of carbon dioxide.
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