Today the global average surface temperature is approximately 1°C warmer than pre-industrial levels. Additional future warming is expected given how past and current greenhouse gas emissions continue to disrupt the planet. This warming is not uniformly spread across the planet’s surface; the average temperature on land is greater than over water, and the average temperature in urban areas is greater than in rural areas.
The same pollution which contributes to climate change also impacts air quality, a significant determiner of human health. Climate change contributes to the prevalence and intensity of wildfires, causing smoke that is hazardous to humans. Increased levels of carbon dioxide in the air causes plants to emit more pollen, which impacts people with allergies. Climate change also exacerbates food insecurity and malnutrition through the disruption of trade and transport, reduced productivity of fisheries, and impacts on agricultural production including the reduced nutritional quality of crops. Extreme weather events, including floods, storms, and heat waves, are more frequent and more intense due to climate change.
Infectious disease rates are increasing due to climate change. For example, mosquitoes carry various diseases including malaria and dengue fever. Climate change is expanding the geographical areas where mosquitoes live, thereby exposing more people to diseases carried by mosquitoes. Additionally, disease related to inadequate water and sanitation are becoming more prevalent due to reduced availability of clean water. A warming climate creates a more favorable environment for pathogens to grow in water, flooding allows for contaminated water to spread and come into contact with humans, and droughts cause people to utilize unsafe water sources.
Health adaptation planning is a process wherein countries and healthcare organizations strategise to meet the climate-induced health needs of a population, and work to make health systems more resilient to climate change. This may include surveillance of, and early warning systems for, hazards like air quality, unsafe water, infectious disease, and extreme weather events. Additional strategies include disaster risk reduction, sustainable food production, and increased access to nutritious food. Climate change is exacerbating existing inequalities in health. In areas where health systems are already not able to meet the needs of the population, a lack of resources creates additional challenges to climate adaptation and resilience. The world’s poorest people are often the least responsible for climate change, and yet are also the most vulnerable to being harmed by its effects.
