Human activity is disrupting Earth’s climate, and the rising emissions of greenhouse gases are accelerating that disruption. (See “Our Changing Climate” box below) Some of the health consequences of climate change are straightforward: warmer temperatures, changes in the hydrologic cycle, increased ground-level ozone, and enhanced pollen production will increase exposure to heat stress, alter patterns of infectious disease, and compromise air quality. These and similar direct impacts of climate change have been well covered in the scientific literature, and what we know of their likely considerable effects is discussed in the sidebar “Direct Impacts of Climate Change” below.
However, we believe that there is another threat, one that is orders of magnitude more potent than those which have been emphasized to date. Here we argue that it is the indirect impacts of climate change—large-scale alterations to Earth’s natural systems—that pose the greatest risk to human health. These changes are curtailing ...
