We considered the possible range of health damages from health care–related GHG emissions specifically. These damages were not included in our earlier estimates of health care sector emission disease burden because of the wide variation in approaches used in their estimation―such as the socioeconomic and emission scenarios considered, inclusion or exclusion of particular health effects, potential adaptive responses, and modeling parameters―that can lead to order-of-magnitude differences in damage factors. Potential impacts of climate change on human health, well-being, and security have been characterized in detail and include thermal stress, flooding and extreme events, radiation, air pollution, infectious disease, malnutrition, and potential conflicts. The World Health Organization estimated that in 2004 climate change caused 141 000 additional deaths worldwide on an annual basis, with a projected 250 000 additional annual deaths that will occur from 2030 to 2050, considering the factors of heat stress, malaria, diarrhea, and malnutrition, and using an average GHG emissions scenario. We linked these future global health damages to the portion of global GHG emissions of the US health care system.