From Health Affairs issue on Climate and Health, first of all:
To accurately describe the health-related costs of climate change, it is important to distinguish between key terms. Climate-sensitive exposures (such as ozone smog air pollution, extreme heat, and extreme precipitation) and health outcomes include those with demonstrated responses to one or more meteorological variables or seasonal patterns.6,7 In recent years, statistical analyses have enabled detection and attribution of the influence of human-caused climate change on extreme weather and other climate-related exposures.8 These climate change–related impacts on the environment include incremental contributions to the frequency and magnitude of extreme rainfall during hurricanes8,9 and increased temperatures during heat waves,10 among others. It is not yet possible to apply analogous methods to directly quantify the attributable portion of climate-sensitive health outcomes to the incremental effects of climate change, as preexisting medical conditions, health vulnerabilities, and multiple exposures are among the many health determinants and causal factors involved. There is currently a knowledge gap that must be addressed for more complete understanding of climate change–related exposure-response relationships.´
Therefore,
Expanded valuation analyses of the costs of climate-sensitive health outcomes are urgently needed to inform public policy. The findings from such studies can be linked to provide a sense of the overall scope of health costs from climate change in communities, cities, states, regions, and countries.
At present, it is difficult to characterize the costs of health harms linked to climate-sensitive exposures in the US. Given the current inability to comprehensively track recent damage, there is limited understanding of the scope of projected future climate-sensitive health risks and costs.
So, there is not any estimate of inaction so far.
