Research roundup: Climate change and mental health

This issue addresses the potential adverse mental health effects of global climate change and the role psychologists can play in addressing those issues.

While the environmental, physical health and economic impacts of global climate change have been frequently researched and reported, the potential adverse mental health effects in the coming years have not received as much consideration.

Climate change is having an array of direct and indirect effects on individuals and society. Mental health professionals will need to be aware of these effects, especially when working with those living in areas that are particularly susceptible to weather events.

Psychologists can prepare by educating themselves on climate change, and in turn, educating patients as well as the public on possible mental health impacts. Psychologists would then be well-equipped to identify communities and populations who will be most in need of their expertise.

Bourque, F. & Wilcox, A. C. (2014). Climate change: The next challenge for public health? International Review of Psychiatry, 26(4) 415-422. Doi: 10.3109/09540261.2014.925851


Examples of climate change and resulting mental health effects from various geographical locations are provided to illustrate the occurrence. In Australia, researchers have reported an increase in the levels of hopelessness and psychological stress among those experiencing environmental degradation and disturbances to farming due to droughts and other weather-related disasters. Severe and persistent droughts in Australia over the last ten years are believed to be correlated with increased generalized anxiety, depression and suicide.

While demographic and socioeconomic status could influence susceptibility to climate-related mental health effects, living in more rural areas where mental health services are not as readily available may also contribute to poor mental health outcomes for those faced with environmental degradation.

Some of the most dramatic climate changes in the world have been experienced by Inuit populations in northern Canada, an area projected to undergo a 10 degrees Fahrenheit temperature increase in this century. As a result of the warming that has already occurred, Canada is experiencing decreasing sea ice thickness, more frequent and powerful storms and disruptions to plant and animal life. Because the Inuit rely so heavily on the natural environment for survival, these alterations are upsetting their very way of life, including their mental health and overall well-being. Compared to the non-Indigenous Canadian population, suicide rates among Inuit people are significantly higher, especially among adolescents. An absence of mental health services only adds to the difficulty.

Devastating weather events such as hurricanes and typhoons are expected to increase in both severity and frequency as a result of climate change. Several studies in the UK reported that severe flooding increased the chance of experiencing psychological distress which was linked to physical illness in both children and adults. Research on the psychological effects of Hurricane Katrina correlated with acute stress, PTSD, violence, depression and suicide.

Many previous studies have shown that because weather disasters are typically viewed as natural occurrences, victims of such events experience psychological responses that aren’t as severe or complex as they often do when trauma is caused by humans. Therefore, the authors suggest that as individuals come to accept the connection between the actions of humans and their contributions to climate change, the grieving and recovery process will be more difficult.

O’Brien, L. V., Berry, H. L., Coleman, C., & Hanigan, I. C. (2014). Drought as a mental health exposure. Environmental Research, 131, 181-187


An increasing number of severe droughts all over the world are forecasted as a result of climate change. A drought is defined as, “below average precipitation and/or intense but less frequent rain events and/or above-normal evaporation resulting in dry soils, reduced plant growth and reduced crop production.” The authors of this study quantified drought with regards to its length and severity by examining rainfall data from the Australian Bureau of Meteorology and creating two indices of comparative dryness. The dryness of different areas was tracked. Summary measures were analyzed to determine various drought characteristics felt during the “Big Dry,” and Australian drought that lasted from 2001 to 2008. Lastly, intense drought conditions spanning Australia were examined in a cluster analysis in IBM SPSS 19.

An annual government-funded survey called the Household, Income and Labour Dynamics in Australia (HILDA) Survey looks at multiple facets of life for the country’s residents, including the job market, family dynamics, overall well-being and socio-economic measures. The authors used the results from the HILDA that was given just prior to the end of the “Big Dry,” rather than the most recent one, so as to ascertain information from the population before recovering from the long drought conditions. Additionally, the iteration of the HILDA that was used also included the Kessler-10, a brief measure of depression, psychological fatigue and anxiety.

Results showed that severe and long-felt periods of drought (20-32 months), strongly correlated with increased distress in rural areas. Individuals living in areas where unrelenting drought is experienced were more likely to demonstrate a subclinical level of moderate distress that could increase the likelihood of mental health issues.

Lowe, S. R., Joshi, S., Pietrzak, R. H., Galea, S., & Cerda, M. (2015). Mental health and general wellness in the aftermath of Hurricane Ike. Social Science & Medicine, 124, 162-170


Mental health issues including post-traumatic stress symptoms (PTSS) and depression have been associated with exposure to natural disasters. In addition, work-related difficulties and physical health problems such as somatic complaints have also been linked. The authors of this study examine predictors of mental health and general wellness in a three-wave study of Hurricane Ike survivors in order to gain insight into the number of survivors who require post-disaster services, as well as to ascertain targets for interventions to assist in population recovery. [When and where was Hurricane Ike?]

Participants were 18 years and older, residing in Galveston or Chambers County for at least one month before Hurricane Ike hit. In Wave 1 of the study, which was conducted about two to five months after Hurricane Ike, 658 participants completed interviews. Wave 2 was conducted at the five to nine month mark with 529 participants, and Wave 3 was conducted 14-19 months after Hurricane Ike. In total, 448 participants completed all three waves.

For each wave, the Post-traumatic Stress Disorder Checklist-Specific version (PCL-S) was used to assess post-traumatic stress symptoms. Depressive symptoms were measured with the Patient Health Questionnaire (PHQ-9). Six items from the Short Post-Traumatic Stress Disorder Rating Interview-Expanded Version (SPRINT-E) evaluated functional impairment and the Center for Disease Control and Prevention’s Health-related Quality of Life -4 (CDC HRQOL-4) looked at the number of days in the prior month that participants’ reported poor physical health.

During Wave 1, exposure to hurricane-related traumatic events, hurricane-related stressors, emotional reactions at the time of the traumatic events, and community-level social assets were measured.

The authors found that the majority of respondents demonstrated resilience, or consistently low levels of problems and/or symptoms over time: 74.9 percent demonstrated resilience from PTSS; 57.9 percent for depression; 45.1 percent for functional impairment; and 52.6 percent for poor health days. Fourteen to 19 months after Hurricane Ike, 51.2 percent of respondents presented with good mental health and 26.1 percent presented with good general wellness. Mental health and general wellness were linked to fewer emotional reactions at the time of the traumatic events and greater collective efficacy (the community’s belief in its capabilities to achieve its goals). Hurricane-related stressors such as loss of belongings, pets and finances as a result of the hurricane were negatively associated with good mental health. Personal loss of property was negatively linked to general wellness. Several domains of post-disaster functioning seem to be influenced by emotional reactions at the time of the traumatic events, loss of property, and collective efficacy.

Lamond, J. E., Joseph, R. D., & Proverbs, D. G. (2015). An exploration of factors affecting the long term psychological impact and deterioration of mental health in flooded households. Environmental Research, 140, 325-334


While most quantitative studies on mental health related to flooding have only examined the immediate and short-term effects, the authors of this study sought to investigate mental health and wellness years after flooding occurred. Previous studies were used to develop a theoretical framework incorporating many exposure, outcome and covariate elements, such as severity of deterioration of mental health, frequency of current anxiety when it rains, and frequency of increased stress level. Exposure factors included duration of flooding, depth of flooding, cost of damage and the need to relocate. Additionally, participants’ age, income level and occupation were considered as covariates.

Reponses to a cross-sectional postal survey of individuals who had experienced flooding during a large flood event throughout England in 2007 were assessed. Characteristics of participants’ home life, the flood event, post-flood stressors and coping strategies were taken into account and then compared to measures of stress, anxiety and depression.

The authors found that income level, severity of the flood event, and whether or not participants were forced to relocate as a result of the flood event were linked to mental health deterioration. Even several years after the flood occurred, many reported moderate symptoms of mental health deterioration and a smaller number reported still suffering extreme symptoms.

Practical Implications

Climate change is likely to have population effects on mental health and well-being. While psychologists may be equipped to assist individuals coping with the effects of various natural disasters related to weather and climate changes, psychologists may also want to consider how they might assist their local populations in developing resilience to anticipated climate change-related impacts, and helping develop proactive strategies to cope. Some psychologists might also want to assist communities in adapting and potentially modifying behaviors so as to reduce some of the human behaviors contributing to climate change and hindering our ability to prepare for it.

Additional resources

APA's Disaster Response Network (DRN) is a group of approximately 2,500 licensed psychologists across the U.S. and Canada who have expertise in the psychological impact of disasters on individuals, families and communities. Psychologists interested in volunteering can visit the Disaster Response Network page on the APA website for more information. 

One of 2008 APA President Alan Kazdin’s initiatives was to establish a task force on psychology and global climate change. Access their report and read copies of their articles in the May-June 2011 issue of the American Psychologist®.

Gifford, R. (2011). The dragons of inaction. American Psychologist, 66(4), 290-302.

Stern, P. C. (2011). Contributions of psychology to limiting climate change. American Psychologist, 66(4), 303-314.

Swim, J. K., Stern, P. C., Doherty, T. J., Clayton, S., Reser, J. P., Weber, E. U., Gifford, R., & Howard, G. S. (2011). Psychology’s contributions to understanding and addressing global climate change. American Psychologist, 66(4), 241-250.

Doherty, T. J., & Clayton, S. (2011). The psychological impacts of global climate change. American Psychologist, 66(4), 265-276.