Q&A: Professor discusses climate change's negative effects on mental health

Associate professor and clinical psychologist, Sarah Lowe's research centers on the long-term mental health consequences of traumatic and stressful life events that affect individuals and communities, including those related to climate change. In a recent study published in Nature Mental Health, Lowe, associate professor of public health (social and behavioral sciences) and psychiatry, and her colleagues from other universities, conducted a systematic review of the link between slow-onset or chronic climate change and mental health.

What is chronic climate change and how does it differ from acute climate change?

Indicators of slow-onset, chronic climate change include long-term changes in precipitation and temperature, sea level rise and other observable changes to ecosystems, and prolonged drought. Acute climate change events are severe and sudden, such as hurricanes, wildfires, floods, and heat waves.

Why is it important to make a distinction between chronic climate change and acute climate change when assessing mental health?

A substantial body of research has documented the mental health consequences of climate change-related disasters, such as hurricanes and major floods, showing that such events are associated with elevated symptoms of post-traumatic stress disorder (PTSD) and other conditions, such as depression and anxiety. This research has, until recently, comprised most of the empirical work on climate change and mental health, yet it is widely acknowledged that disasters are only one of several climate change-related indicators.

Expanding our focus to other climate change exposures, including slow-onset, chronic changes, provides more insight into the ways in which climate changes shape mental health and well-being, as the nature and severity of symptoms linked to these exposures might be substantially different from those that emerge in the aftermath of disasters. This work can have implications for treatment and prevention of mental health symptoms as climate change escalates.

What links did you find between chronic climate change and mental health, and is it possible for people impacted by chronic climate change to have symptoms of PTSD?

The 57 studies in our review collectively found that chronic climate change indicators have been associated with depression, anxiety, and suicidality. In addition, qualitative studies identified links with a range of negative emotions, such as grief, worry, and frustration.

One study examined PTSD symptoms and found that they were not significantly associated with exposure to chronic drought. However, it is important to note that this was only one study, and it is possible that chronic indicators are in some cases linked to PTSD symptoms. It is therefore premature to say that a trauma-based framework, versus one that focuses on the depression, anxiety, and related emotions, is not applicable to chronic climate change.

Overall, our review demonstrated the need for more research in this area—both to refine conceptual models and to inform clinical and public health interventions.

Key directions for future research include studies in low- and middle-income countries; mixed method and longitudinal designs; the development of novel measures to assess the negative emotional impacts identified in qualitative studies; and evaluation of strategies to mitigate climate change-related distress.