US Climate and Health Alliance

Human Health: Impacts, Adaptation, and Co-Benefits


The health of human populations is sensitive to shifts in weather patterns and other aspects of climate change (very high confidence). These effects occur directly, due to changes in temperature and precipitation and occurrence of heat waves, floods, droughts, and fires. Indirectly, health may be damaged by ecological disruptions brought on by climate change (crop failures, shifting patterns of disease vectors), or social responses to climate change (such as displacement of populations following prolonged drought). Variability in temperatures is a risk factor in its own right, over and above the influence of average temperatures on heat-related deaths. {11.4} Biological and social adaptation is more difficult in a highly variable climate than one that is more stable. {11.7}Until mid-century climate change will act mainly by exacerbating health problems that already exist (very high confidence). New conditions may emerge under climate change (low confidence), and existing diseases (e.g., food-borne infections) may extend their range into areas that are presently unaffected (high confidence). But the largest risks will apply in populations that are currently most affected by climaterelated diseases. Thus, for example, it is expected that health losses due to climate change-induced undernutrition will occur mainly in areas that are already food-insecure. {11.3}In recent decades, climate change has contributed to levels of ill health (likely) though the present worldwide burden of ill health from climate change is relatively small compared with other stressors on health and is not well quantified. Rising temperatures have increased the risk of heat-related death and illness (likely). {11.4} Local changes in temperature and rainfall have altered distribution of some water-borne illnesses and disease vectors, and reduced food production for some vulnerable populations (medium confidence).

Resource Type
Intergovernmental Panel on Climate Change (IPCC)
Resource URL
Organization Type
Other gov
Health and Human Impact
Climate and Environmental Impact

Resources main page