Basic Information

Human Health
All living creatures depend on the environment for health and well-being. Earth has provided dependable sources of food, water, and other natural resources for millennia. Until recently, a relatively stable and predictable climate has provided the physical safety and comfort necessary for life to flourish. By changing the composition of the atmosphere, humans almost certainly impact the environment's ability to support life as it now exists.

Scientists have recently begun to study climate change impacts on human health, yet many of the findings remain unclear.1 Scientists do know that some impacts will be beneficial. Milder winters, for example, could result in fewer deaths during the coldest months in temperate climates. In tropical and sub-tropical regions, extremely high temperatures could reduce the viability of disease-carrying mosquito populations.2

Overall, however, scientists believe climate change impacts on human health will be largely negative. Impacts will vary across regions, and communities already burdened by resource shortages, disease, and disability will face the most severe health impacts. Rural tribes that lack transportation and healthcare infrastructure, for example, will confront some of the most difficult challenges. During pandemics, Indigenous Peoples suffer higher infection rates, and more severe symptoms and death than the general population.3 Indigenous Peoples suffer diabetes at a rate nearly twice that of general US population, leaving them even more susceptible to extreme heat, air pollution, and related negative health impacts.4 Understanding and addressing the specific health vulnerabilities Indigenous peoples will face in tandem with climate change is essential for guaranteeing their safety and wellbeing.

Tribal health is inextricably linked to the environment and relies on interconnected social and ecological systems that are being disturbed by climate change.5 As these changes persist, the health of Indigenous communities and individuals will be impacted through changing land, water, and food systems. While the physical health of Indigenous Communities may decline because of impacts from climate change, their mental health will also be negatively affected should they no longer have access to the land, water, and species they rely on for ceremonies and spiritual practices. The Yurok Tribe is concerned about the health of their Tribal members as a result of the declining health of their environment, particularly the rivers they steward. They recognize that healthy people are born from healthy ecosystems and believe that if their river and surrounding ecosystems are sick, they too, are sick.6 Tribal views of health differ from western views of health and take the health of the environment into great consideration.

Infectious diseases
Health officials expect vector-borne diseases-those passed by insects, rodents, and other host carriers-to pose one of the biggest threats to human health.7 Disease-carrying mosquitoes require stagnant water and warm conditions to thrive — conditions that will be enhanced by warmer temperatures and more-frequent storms, both trademarks of a changing climate. Rodents and ticks in temperate climates will proliferate after mild winters and spread illnesses such as Lyme disease and tick-borne encephalitis.8 Higher levels of spring runoff lead to increased food sources for mice. The 1993 hantavirus outbreak on the Navajo Reservation was linked to heavy snow and rainfall, which helped the rodent population expand to ten times its normal numbers due to the increase in food availability.9 Under flooding conditions, increased rodent-human interactions are shown to increase rates of leptospirosis, tularaemia, and viral hemorrhagic disease.10

Diarrheal diseases are one of the leading causes of death worldwide. In 2017, 1.6 million people died because of diarrheal disease.11 This symptom of infection caused by a host of bacterial, viral, and parasitic organisms burgeons during both floods and droughts. Communities living without consistent access to clean water are especially vulnerable. Preventing not only diarrheal diseases, but infectious diseases in general will become increasingly more challenging in a changing climate.

Extreme temperatures
Extreme events such as heat waves and cold snaps may become more deadly as the climate shifts. Although varying by region, scientists predict an overall increase in heat related mortality as summertime temperatures increase.12 People with pre-existing conditions and the very young, old, or frail will be most at-risk. Scientists also expect an increase in deaths, disease, and injury from other extreme events such as fires and hurricanes.13

Although temperature extremes are becoming more common, some Indigenous Communities have long since adapted to scorching temperatures. The Tohono O’odham Nation is on the Southern Border of Arizona, situated in the Sonoran Desert. As temperatures can exceed 110°F in the summer, they have adapted to the hot, dry environment. The Tohono O’odham people traditionally constructed wattos – open air shade structures with dirt floors that they occasionally wet – to combat high temperatures.14 As temperatures in the arid desert become more intense, the Tohono O’odham people are beginning to rely more on air conditioning to stay cool. Reliance on air conditioning, particularly in this region, can be problematic as heat waves and extreme weather can cause electrical failure and blackouts. While air conditioning in these communities is becoming essential to ensure the safety of their residents, Tribes in regions facing less extreme temperatures can learn from their practices and model ways of protecting themselves against extreme heat.

Food security and impacts to traditional medicines and ceremonial practices
A higher rate of crop failure will likely increase malnutrition, especially for children in developing nations. Regional famines may also swell. Extreme events could cause water shortages, leading to dehydration, decreased access to potable water, and a host of associated complications.15

As it becomes more difficult to harvest traditional foods due to crop failure and changing weather patterns, Indigenous people will rely more heavily on Western food and western food systems. As is the trend with rural areas, some Reservations are food insecure and located in food deserts. Combined with a sudden inability to grow healthy foods alone, Indigenous peoples may resort to consuming the highly processed, non nutritious foods available to them at nearby convenience stores and gas stations. This will adversely affect their health and may increase rates of diseases associated with high consumptions levels of processed foods, such as heart disease, diabetes, and obesity.

In addition to agricultural harvest complications and its effects on the health of Indigenous Peoples, subsistence harvests will also be impacted. As temperatures warm, deer are migrating into moose territories and habitats. Deer often carry ticks, which introduce diseases to moose populations. It is predicted that as a result, deer populations may increase, and moose populations will decrease.16 Similarly, salmon populations are decreasing due to warming water temperatures, leaving Tribes without yet another subsistence staple. Salmon, moose, and many more species are important subsistence foods to Tribes across North America, and should populations decline, Tribes will be forced to find a replacement.

Air Quality
Air quality will be degraded under climate change, especially in urban areas where greenhouse gas emissions are most intense. Concentrations of ground-level ozone, a primary component of urban smog, are rising in most areas. Forest fires and windblown dust from desertification also negatively affect air quality. Also, studies have shown that allergies caused by pollen worsen as the seasons warm.17 As seasons become warmer for longer periods of time, the pollen season itself also extends. This increases the potency of pollen and the duration of its effect on people, which causes longer allergy seasons and can further disturb those with lung conditions such as asthma.18 Mold is another common air quality concern that can be exacerbated by climate change, as it thrives in warm, humid environments – those that will be seen in flooded areas. Mold, like pollen, can trigger asthma attacks and harm respiratory systems. Changes in air quality due to climate change will only further health complications faced by those with respiratory illnesses and those already living in areas with poor air quality.

Mental Health
Mental health complications can be brought on or exacerbated by climate change. Depression, anxiety, and post-traumatic stress disorder are the most common impacts of climate change on mental health.19 These impacts can linger for months or years, and the continued effects of climate change may further delay recovery. Those displaced because of extreme weather events or other climatic factors are at a higher risk of developing PTSD and general anxiety disorders than those who do not relocate. Relocation, however, can lessen stressors caused by a changing climate over time.

The changing climate may also result in the demoralization of entire communities as the land changes and resources grow scarce, referred to as solastalgia.20 Tribes, still dealing with the consequences of Euro-American incursions into the Americas, will be forced once again to adapt to a changing world. Alaska Natives in coastal villages have already been forced to leave their ancestral homelands to relocate inland as sea levels rise. Traditional hunting practices are affected as sea ice becomes too unstable for travel and the timing of animal migration changes. The ranges of plants used for food, medicinal, spiritual, and other purposes are changing. Reliance on western foods and western food systems will increase as traditional foods become more difficult to cultivate. Tribal cultural practices may become impossible to continue, and tribes will once again be forced to adapt to cultural practices and philosophies imposed on them largely by others.

Climate grief will be rampant across the world as the environment continues to change, but Indigenous Communities may be impacted much more than others due to their connectivity with the natural world around them. Globally, we may find solace and healing in climate hope. Collectively, we may find emotional and spiritual resilience to fully engage with the climate crisis, ultimately allowing us to consider new ways of life in a rapidly changing world.21

More information
For more information about climate change and human health, visit the World Health Organization's Climate Change and Human Health page at:

  1. McMichael, A.J., et al. (2003). Climate change and human health: Risks and responses. Geneva, Switzerland: World Health Organization.

  2. Confalonieri, U., et al. (2007). Human health. In Climate Change 2007: Impacts, Adaptation and Vulnerability. Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Parry, M.L., Canziani, O.F., Palutikof, J.P., van der Linden, P.J., & Hanson, C.E. (Eds.). Cambridge, UK: Cambridge University Press, 391-431

  3. Power, T., Wilson, D., Best, O., Brockie, T., Bourque Bearskin, L., Millender, E., & Lowe, J. (2020). COVID-19 and Indigenous Peoples: An imperative for action. Journal of clinical nursing, 29(15-16), 2737–2741. Retrieved October 31, 2022 from

  4. USGCRP, 2018: Impacts, Risks, and Adaptation in the United States: Fourth National Climate Assessment, Volume II [Reidmiller, D.R., C.W. Avery, D.R. Easterling, K.E. Kunkel, K.L.M. Lewis, T.K. Maycock, and B.C. Stewart (eds.)]. U.S. Global Change Research Program, Washington, DC, USA, 1515 pp. doi: 10.7930/NCA4.2018.

  5. Donatuto, J., Campbell, L., Cooley, C., Cruz, M., Doyle, J., Eggers, M., Farrow Ferman, T., Gaughen, S., Hardison, P., Jones, C., Marks-Marino, D., Pairis, A., Red Elk, W.N., Sambo Dorough, D., & Sanders, C. (2021). Health & Wellbeing. In Status of Tribes and Climate Change Rep.ort [Marks-Marino, D. (ed.)]. Institute for Tribal Environmental Professionals, pp. 159–173

  6. Yurok Tribe. (2014).Yurok Tribe Climate Change Adaptation Plan for Water and Aquatic Resources. Yurok Tribe. Retrieved June 7, 2023 from

  7. World Health Organization. (2020). Vector-borne diseases. Retrieved October 31, 2022 from,either%20parasites%

  8. McMichael, A.J., et al. (2003).

  9. Ibid.

  10. Confalonieri, U., et al. (2007).

  11. Dadonaite, B., Ritchie, H., & Roser, M. (2019). Diarrheal diseases. Our World in Data. Retrieved October 31, 2022 from

  12. McMichael, A.J., et al. (2003).

  13. World Health Organization. (2005). Climate and health. Retrieved July 1, 2009 from

  14. Wall, D. (2017). The Tohono O’odham: Desert People in a Changing Environment. Institute for Tribal Environmental Professionals. Retrieved June 7, 2023 from

  15. Confalonieri, U., et al. (2007).

  16. Weiskopf, S., Ledee, O., & Thompson, L. (2019). Climate change effects on deer and moose in the Midwest. The Journal of Wildlife Management. Vol 83, issue 4, p 769-781. Retrieved June 7, 2023 from

  17. Ibid.

  18. American Public Health Association & ecoAmerica. (N.D.). Making the Connection: Climate Changes Allergies and Asthma. American Public Health Association & ecoAmerica Retrieved June 7, 2023 from

  19. Palinkas, L., & Wong, M. (2020). Global climate change and mental health. Science Direct, vol. 32, p 12-16. Retrieved November 7, 2022 from

  20. Albrecht G, Sartore GM, Connor L, Higginbotham N, Freeman S, Kelly B, Stain H, Tonna A, Pollard G. Solastalgia: the distress caused by environmental change. Australas Psychiatry. 2007;15 Suppl 1:S95-8. doi: 10.1080/10398560701701288. PMID: 18027145.

  21. Carrington, K., & Hollyhock Leadership Institute. (N.D.). Climate Hope. Climate Hope. Retrieved June 7, 2023 from