Communities whose livelihoods depend directly on the natural environment, such as those engaged in agriculture, fishing, and tourism, are more significantly impacted by climate changes. Heat acts as both a physiological and psychological stressor.

Studies have shown that heatwaves increasingly affect individuals at the extremes of age, those who are overweight, those with pre-existing mental health issues, people from lower socioeconomic backgrounds, and those involved in prolonged physical activities. Research indicates that rising temperatures lead to negative mental health outcomes, including increased use of emergency mental health services. Higher temperatures add stress that can overwhelm those who are already psychologically vulnerable.

Generally, extreme heat is uncomfortable and, over time, can cause fatigue, reduce positive emotions, and increase negative emotions such as rage and anger. Researchers have established a causal relationship between heat and interpersonal aggression: as temperatures rise, people’s behavior becomes more aggressive. This may be due to increased arousal and irritability, leading to decreased attention and self-regulation.

Higher environmental temperatures also result in poor sleep, which can increase irritability and negatively impact cognition, reducing the ability to resolve conflicts peacefully. During heatwaves, people might temporarily move to more protected areas, potentially leading to social conflicts with residents of those areas.

Additionally, hospital admissions for pre-existing mental health conditions like dementia, mood disorders, stress-related, and somatoform disorders rise during heatwaves. Heat can also reduce physical activity and increase alcohol consumption, leading to higher incidences of domestic violence.