Robust pollen seasons, poor air quality, increased growth of mold, recurrent flooding, extreme heat, damaging drought, wildfires, and spread of insect vectors are some of the environmental consequences of climate change that affect health, including mental health. Vulnerable populations are at particular risk.
Environmental changes such as robust pollen seasons are occurring, over a larger geographic area, as average temperature and CO2 levels rise. The amount of pollen in the air has been increasing and will continue to increase as climate change worsens, causing increased allergy symptoms for a large percentage of the American public who have hayfever and/or asthma.
Increases in air pollution result when heat and light interact to produce ozone from the emissions of electric power plants or other processes that depend on energy produced by burning fossil fuels. Pollutants (ozone and particulate matter), including wildfire, smoke, dust and pollen, spread over large areas, irritating lungs and causing symptoms (wheezing, coughing, and shortness of breath) in people with asthma or other lung conditions. Particulates include wildfire smoke, dust, and pollen.
Recurrent flooding from storm surges, sea level rise, and/or heavy precipitation can cause mold growth affecting people with mold allergies or asthma or both. It can also cause displacement and social disruption leading to mental health problems. For children, disruption can cause significant behavior problems; for adults it can lead to alcoholism or substance abuse.
Extreme heat is the most frequent cause of mortality due to extreme weather. About 700 Americans die each year because of heat illness; many more receive care in emergency rooms and hospitals. Heat can intensify lung, heart, and kidney conditions. Elderly individuals who live alone, people who work outside, children and school athletes who spend time exercising outdoors, and the homeless are at greater risk for heat illness, heat exhaustion, or heat stroke.
Drought can adversely affect agriculture and livestock and amplify wildfires, causing health impacts over large distances. Forest fires put small particles into the air, irritating the airways of those who have lung conditions (asthma, obstructive chronic pulmonary disease, cystic fibrosis, etc.) or cardiac conditions and drive emergency room visits and hospitalizations.
Insect vectors are spreading to new geographic areas and multiplying more quickly in association with climate change. Rising average temperatures lengthen the vector breeding season; and increased rainfall, flooding and humidity create breeding grounds for disease-carrying insects such as mosquitoes. As a result, infections such as Lyme Disease, Dengue Fever, Chikungunya, and Zika are threatening additional populations.
Mental health disorders are among the most distressing of the health effects of climate change. Victims of natural disasters often suffer elevated levels of anxiety, depression, post-traumatic stress, interpersonal and family conflict, grief, behavioral issues, and child development problems.
Vulnerable populations: Climate change threatens the health and well-being of all humans, but some groups are disproportionately harmed more than others. Among the populations most vulnerable to climate change are young children, older adults, those living in poverty, and individuals whose health is already compromised by illness.