The role of mitigation, adaptation, and/or benefits of climate change
To the extent that climate change alters our environment, it will create incentives for innovation and adaptation that mitigate the damages from climate change. The document should note this possibility and how it affects the likely impacts of climate change.
For example, climate change is likely to unfold slowly and people may migrate from hot regions (e.g., Arizona) to more temperate regions (e.g., Minnesota) and this would mitigate the adverse impacts on health (although people would incur migration costs). Further, climate change is likely to lead to innovation that mitigates the ozone related health impacts; it seems reasonable to assume that in the absence of regulation of GHS, new medicines that lessen the health impacts of ozone will be developed. Moreover, advances in technology and the development of public health programs (e.g., cooling centers) are likely to lessen the negative welfare impacts of heat waves.
Similarly, the document would appear more balanced if it also highlighted whether particular regions of the US would benefit, and to what extent these positive impacts would mitigate negative impacts elsewhere in the United States. For example, it might be reasonable to conclude that Alaska will benefit from warmer winters for both health and economic reasons. Deschenes and Moretti (2007 Review of Economics and Statistics) demonstrate that extremely cold days are more dangerous to human health than extremely hot days. Please add this paper to the literature review in Section 7(a) of the TSD.
Further, there should be a consideration of the fertilizing effect of CO2, which may overwhelm the negative impact of additional hot days on agricultural yields in some regions of the US. In others regions, the net effect is likely to be negative.