Climate Change and Public Health
Climate change impacts health by changing people’s exposure to hazards (environmental factors) and their ability to adapt or respond to them (personal factors). Health threats include exacerbated or worsening preexisting medical conditions, increased stressors, and new problems like heat-related illnesses and flooding.
Communities of color, low income and immigrant groups often experience disproportionate impacts from climate change. A community centered, health impact approach is important for Public Health.
Extreme weather events such as heat waves, storms, and floods are a significant threat to human health. They can lead to a loss of life and cause damage to critical infrastructure, such as roads, power lines, water supply, and health care facilities. This can result in financial stress for people, and increase mental anguish.
Climate change has made these events more likely and severe. To track the evidence, Carbon Brief has mapped – to the best of our knowledge – every extreme event attribution study published up to May 2022. The chart below shows the number of studies for each type of event, with categories indicating whether the event was made more likely or severe by human activity (red), less likely or not affected (yellow), or had no influence on the event at all (blue).
Preparation and adaptation actions are needed to reduce poor health outcomes and disruption to infrastructure during and after extreme weather events. Special attention should be given to vulnerable populations, including children, older adults, and those with chronic conditions or who are living in low-income communities.
Air pollution is a threat to public health and climate change impacts it in several ways. It exacerbates and amplifies existing health risks and exposes people to new ones, such as increased risk of insect-borne diseases. It also reduces life expectancy and is a leading cause of premature death.
Human activities contribute to air pollution through carbon dioxide emissions from burning fossil fuels (coal, gasoline, and natural gas) for cars and airplanes; fumes from power plants and factories; smoke from wildfires; ash and gases from volcanoes; and dust from mining operations. These pollutants, along with particulate matter, can cause breathing difficulties and lead to heart disease and lung problems. They can also harm animals and plants and contaminate water, food, and land.
Actions to reduce air pollution help mitigate climate change and improve public health by cutting short-lived greenhouse gas emissions, reducing ambient air pollution, and decreasing exposure to toxins. They can also reduce inequalities in exposure to climate change hazards, as many actions can benefit people of all incomes and ages while helping advance equity.
Heat stress is a health threat that can cause illness and death. It is a risk factor that increases with natural aging, and can be worsened by health conditions such as heart disease and respiratory illnesses. It can also be exacerbated by spending time in buildings without adequate cooling systems, outdoor recreational activities, and being homeless. People living in low-income and disadvantaged communities are particularly vulnerable to climate change impacts including increasing temperatures, poor air quality, flooding events, and spread of vector-borne diseases.
This NIH initiative supports research on ways to reduce health risks, promote adaptation, and build resilience among individuals, communities, nations, and the global ecosystem. These efforts include expanding access to healthcare, paid family and medical leave, and affordable housing, as well as addressing longstanding differences in health outcomes that reflect poor living conditions, racism and other forms of discrimination, and psychological stresses.
The availability of nutritious, tasty and affordable food is an essential aspect of public health. Climate change poses threats to this basic need through many channels, including by increasing the occurrence of extreme weather events, affecting food systems, and exacerbating the transmission of air-, water-, and vector-borne diseases. These climate-sensitive health risks are disproportionately felt by those with the lowest socioeconomic status, such as the poor and marginalised communities, women, children, ethnic minorities, migrants or displaced persons, and older populations.
A hazard, exposure, and vulnerability framework has proven useful for exploring the connections between climate change and human health. The Lancet Countdown CCIEVIs are based around this framework and include a range of indicators covering health, climate, and demographics. However, data standards remain an area of concern for these indicators. This may partly explain why attribution of climate-related changes to health outcomes is not straightforward.