When people think about climate change, they probably think first about its effects on the environment, and possibly on their physical health.
But climate change also takes a significant toll on mental health, according to a new report released by the American Psychological Association and ecoAmerica entitled Mental Health and Our Changing Climate: Impacts, Implications, and Guidance.
Climate change-induced severe weather and other natural disasters have the most immediate effects on mental health in the form of the trauma and shock due to personal injuries, loss of a loved one, damage to or loss of personal property or even the loss of livelihood, according to the report.
Terror, anger, shock and other intense negative emotions that can dominate people's initial response may eventually subside, only to be replaced by post-traumatic stress disorder.
As an example of the impacts natural disasters can have, among a sample of people living in areas affected by Hurricane Katrina in 2005, suicide and suicidal ideation more than doubled, one in six people met the diagnostic criteria for PTSD and 49 per cent developed an anxiety or mood disorder such as depression, said the report.
The impacts of climate on mental health are not relegated to disasters alone. There are also significant mental health impacts from longer-term climate change. Changes in climate affect agriculture, infrastructure and livability, which in turn affect occupations and quality of life and can force people to migrate.
These effects may lead to loss of personal and professional identity, loss of social support structures, loss of a sense of control and autonomy and other mental health impacts such as feelings of helplessness, fear and fatalism.
High levels of stress and anxiety are also linked to physical health effects, such as a weakened immune system. Worry about actual or potential impacts of climate change can lead to stress that can build over time and eventually lead to stress-related problems, such as substance abuse, anxiety disorders and depression, according to research reviewed in the report.
Climate change is likewise having mental health impacts at the community level. Both acute and long-term changes have been shown to elevate hostility and interpersonal and intergroup aggression, and contribute to the loss of social identity and cohesion, said the report. Certain disadvantaged communities, such as indigenous communities, children and communities dependent on the natural environment can experience disproportionate mental health impacts.
The key to combating the potential negative psychological effects of climate change, according to the report, is building resilience. It includes a section dedicated to offering guidance to aid professionals in supporting and promoting the mental health of individuals and communities and helping them build psychological resilience. One recommendation is to guide people to support and maintain their social networks.
"Individuals' personal capacity to withstand trauma is increased when they are connected to their networks off- and online," said the report. "Researchers have found that higher levels of social support during and in the aftermath of a disaster are associated with lower rates of psychological distress."
The report also emphasised that adopting environmentally friendly policies and lifestyle choices can have a positive effect on mental health. For example, choosing to bike or walk to work has been associated with decreased stress levels. If walking or biking to work is impractical or unsafe, use of public transportation has been associated with an increase in community cohesion and a reduction in symptoms of depression and stress, according to the report. Also, increased accessibility to parks and other green spaces could benefit mental health as spending more time in nature has been shown to lower stress levels and reduce stress-related illness, regardless of socioeconomic status, age or gender.