Rapidly increasing climate change poses serious global threat to mental health - IPCC

Over the past decade, research and public interest on the effects of climate change on mental health have been increasing, as the number of individuals and communities exposed and vulnerable to climate change hazards grows.

Weather and climate extremes such as storms, floods, droughts, heat events and wildfires can be traumatic and have immediate impacts on mental health. Slow onset events like changing seasonal and environmental norms, sea level rise and ice patterns can also affect people’s mental wellbeing.

Growing evidence confirms that the consequences of rapid, widespread and pervasive climate events may include anxiety, PTSD, higher rates of suicide, a diminished sense of wellbeing (stress, sadness), ecological grief, a rise in domestic violence, cultural erosion and diminished social capital and social relations.

As scientists who contributed to the latest IPCC report Climate Change 2022: Impacts, Adaptation and Vulnerability, we are pleased that this Sixth Assessment Report (AR6) assesses climate change impacts on mental health for the first time in detail, representing a major advancement and new contribution.

Significant threats

The Earth will likely reach 1.5ºC of warming above pre-industrial levels by 2040 under intermediate and high greenhouse gas emissions scenarios, bringing with it higher temperatures on land and in the ocean, declining sea ice, more heat waves, more rainfall in some regions and a greater chance of drought in others.

With increasing exposures to these hazards comes greater incidences of negative mental health outcomes. The findings outlined in the report confirm the depth, breadth and significance of the ways climate change impacts mental health. This synthesis of global research indicates that these negative mental health outcomes are on the rise and unequally distributed due to climate change.

Here are three things that the latest IPCC report tells us about climate change and mental health in North America.

1. There is greater scientific understanding about the ways that climate change negatively impacts mental health.

When the IPCC Fifth Assessment Report (AR5) was published in 2014, there was emerging yet limited research on mental health outcomes. The report mentioned that climate change could affect mental health, but there wasn’t enough published research available then to fully assess its impacts.

As the volume of research on climate change and mental health has grown, this new report is now able to assess its impact. Researchers have been able to examine how both climate and weather extremes such as storms, floods, droughts and fires and slower-onset climate changes such as warming temperatures and changing environmental norms interact with people’s vulnerabilities such as socio-economic inequities, age, gender, identity, occupation and health and lead to a diverse range of negative mental health outcomes.

For example, a synthesis of global literature found that those exposed to flooding events — such as the floods in southern British Columbia in 2021, in Ottawa in 2019 and Alberta in 2013 — experience PTSD, depression and anxiety in the short term and have elevated risks for these mental health outcomes in the long term. Similar mental health outcomes were found for those exposed to wildfires and related smoke, such as the wildfires in the Northwest Territories in 2014, Fort McMurray, Alta., in 2016 and Lytton, BC, in 2021.

Our own work with Inuit in Nunatsiavut, Labrador, demonstrates the ways in which slower, cumulative impacts from rising temperatures, declining sea ice and changing seasonal, animal and plant patterns disrupt land-based activities and livelihoods, leading to negative consequences for mental and emotional wellbeing. This includes strong emotional reactions (stress, anger, fear and distress), ecological grief and loss, expressions of anxiety and depression and loss of cultural knowledge and place-based identities and connections.

2. The mental health impacts of climate change are unequally distributed.

Climate change works across intersecting social determinants of health — factors such as age or gender that influence health and how people live — to disproportionately affect certain groups.

For example, AR6 demonstrates that some people and communities are most at risk for increasingly worsening mental health outcomes, due to their proximity to the hazard, their reliance on the environment for livelihood and culture and their socioeconomic status:

• Agricultural communities already experiencing drought or changing environmental conditions.


• People living in areas exposed to wildfires and floods.


• Indigenous Peoples and those closely dependent on the natural environment for livelihoods and culture.


• Women, the elderly, children and young people and those already experiencing chronic physical and mental health issues.
  
  

  Climate change impacts on mental health and adaptation responses in North America. (IPCC AR6 Working Group II report, Climate Change 2020: Impacts, Adaptation, and Vulnerability.)