Climate change and health: Impacts and risks
Climate change affects human health in a variety of ways. Extreme changes in the weather and environment can increase existing health problems, as well as creating new ones.
Public health impact
Extremes in weather and temperature, increased pollution and environmental toxins, and changes in food security can all cause physical and mental health problems.
Climate change is affecting some of the essential factors that influence human health, including:
- safety of shelter
- air quality
- quality, safety, and supply of drinking water
- food availability
- nutrition levels in food
As climate change progresses, researchers expect an increase in related health issues.
According to the World Health Organization (WHO), researchers predict that certain effects of climate change will contribute to an increase of about 250,000 deaths per year between 2030 and 2050 from conditions such as:
- heat stress
Climate change can also contribute to migration, as factors such as drought and plummeting fish stocks can lead rural populations to move into urban centers.
Living in urban areas can increase the risk of disease due to overcrowding and higher temperatures.
Extreme weather and natural disasters can be traumatic and stressful for the people whom they affect.
People may undergo displacement, injury, the loss of their home and possessions, or the loss of loved ones.
Extreme heat may also have a more significant effect on people with mental health conditions. According to the Centers for Disease Control and Prevention (CDC), suicide rates increase with higher temperatures.
The CDC suggest that climate change and higher temperatures have a negative effect on depression and other mental health conditions.
Extreme temperatures can also change how certain medications, such as schizophrenia treatments, work in the body. In addition, they may affect people’s ability to regulate their body temperature correctly.
Researchers have found that natural disasters, such as Hurricane Katrina, have negative mental health effects on those involved, including post-traumatic stress disorder and high levels of anxiety. Floods, heat waves, and wildfires may also create these issues.
Concerns about the effects of climate change may also be a source of increased anxiety or despair for some people.
According to the WHO, climate change is likely to cause an increase in insect-transmitted infections and waterborne diseases.
The reason for this is that changes in climate could increase the length of the seasons during which insects transmit infections. These changes could also expand the area in which they occur.
Countries such as the United States may be at risk of an increase in both current waterborne and insect borne diseases and diseases that are not yet present in the area.
Changes in rainfall patterns could also increase the risk of waterborne diseases and infectious diseases that cause diarrhea.
Heat- and weather-related conditions
Rising temperatures can cause or exacerbate a wide range of severe health problems. Prolonged exposure to extreme heat can cause:
- heat exhaustion
- muscle cramps
- worsening of existing conditions, such as respiratory and heart conditions
Extreme changes in temperature are likely to have a more significant effect on certain groups of people:
- older adults
- people with chronic health conditions
- people with less economic stability
- people who are socially isolated
- those living in urban areas, where heat levels will be several degrees warmer than they are in areas with fewer buildings
An increase in extreme weather conditions poses a serious risk to health. Hot, dry conditions and droughts can cause:
- dust storms
- a decrease in water supply and quality
- reduced quality of air
- lack of food
All of these factors can have severe effects on human health, including:
- increased risk of infections
- respiratory problems from smoke exposure
Severe flooding and flash floods can be very dangerous. According to the CDC, approximately 98 people die each year in the U.S. as a result of flooding.
While the immediate dangers of flooding include drowning and injury from damaged buildings, other risks of flooding include:
exposure to toxic chemicals in runoff
displacement and homelessness, which can affect physical and mental health
an increase in respiratory diseases from living in damp environments
mold, which can reduce indoor air quality
Who is most at risk?
Although all populations are likely to experience the effects of climate change, certain areas of the world are more at risk than others.
Areas most at risk from the health effects of climate change include:
- coastal regions
- mountainous regions
- polar regions
- small islands
- countries with a lack of healthcare facilities
- developing countries
Certain groups of people are also more at risk from the health hazards of climate change. They include:
- children, particularly those living in developing countries
- older adults
- people with certain preexisting health conditions
- people who are economically disadvantaged
- people who are socially isolated