“We are on a highway to climate hell with our foot still on the accelerator.”
This was António Guterres, secretary-general of the United Nations, opening at the COP 27 addressing the world leaders. This man-made climate disaster is primarily caused by greenhouse gas emissions resulting in the rise of earth’s temperature. Consequently, we are increasingly exposed to extreme weather events, sea-level rise and an overall dramatic change in the earth’s climate. The negative effects of climate change are far-reaching and include, but are not limited to, droughts, the spread of disease, wildfires, tropical storms, ecosystem collapse and much more (IPCC, 2022). In summary, the world is in crisis.
Climate change affects human life in many ways with different studies showcasing the economic, social and physical health outcomes. Additionally, previous research described direct (for example, traumatic effects of extreme weather events), indirect (for example, emotional pressure due to uncertainty of the future) and psychosocial (for example, the effect of droughts on a community) psychological impacts on population (Doherty et al., 2011).
However, the effects of the global climate crisis on mental health has been overlooked in the existing literature, with only limited research focusing on this. The effects of climate change on mental health are expected to be even more evident in cities and towns located in geographical areas that are already frequently affected by extreme weather events, such as specific coastal areas. One very relevant example is South Florida, with the counties of Miami-Dade and Broward being particularly susceptible to tropical cyclones, followed by sea level rise and storm surge, which can in turn lead to flooding and inundation.
For this reason, Monsour and colleagues (2022) decided to estimate how many people would experience and develop mental health symptoms as a result of these adverse climate conditions.
The exposures of this study were tropical cyclones, sea level rise, and storm surge, while the outcome was mental health symptom prevalence, specifically for post-traumatic stress disorder (PTSD), anxiety, and major depressive disorder.
The methodological process employed by the authors followed four stages:
- Associations between tropical cyclone score and mental health symptoms: Three datasets were harmonised to develop logistic regression models. The models included other variables that were associated with exposures and outcomes, i.e. demographic information, previous traumatic experience, and post-disaster support. To deal with missing information, multiple imputation by chained equation was used.
- Impact of exposure to tropical cyclones on mental health symptoms risk: One additional model was developed to estimate effect sizes with no additional variable included.
- Percentage of people affected by sea level rise and storm surge (Miami-Dade and Broward Counties): Inundation mapping through digital elevation models was used to determine the impact of several inundation scenarios, which were calculated using one equation to estimate the number of people impacted.
- Prevalence of people with elevated mental health symptoms: Another equation was used as a result of combining the previously mentioned models with the inundation mapping. This was done by averaging the predictions specific to each dataset for mental health symptoms in the two counties.
Numerous significant associations were found following each stage.
The logistic regression models highlighted a number of variables associated with elevated mental health symptoms risk (p values < 0.05 to 0.001), including having a Black and Hispanic ethnicity, being a female, and having an existing mental health disorder. As for other variables, such as advanced age, different results were shown depending on the dataset used. Of note, some rather odd results emerged as well, such as an association between better physical health and a higher risk of mental health symptoms.
When these variables were not taken into consideration, it was clear from the results in all the datasets that greater tropical cyclone exposure was associated with developing mental health symptoms (p values < 0.02 to 0.001).
In all the scenarios considered, the inundation mapping of the two counties illustrated the significant impact of sea level rise and storm surge, with more severe effects on densely populated areas. Even in the least case scenario, a significant impact was shown for more than 180,000 people, while a more likely scenario suggested that the catastrophic flooding would impact more than 4 million people as well as destroy both counties almost completely.
Finally, following the exposure to tropical cyclones, it was estimated that, in the most extreme scenario, as well as a more realistic scenario, mental health symptoms would be experienced by 1 to 2 million people, with PTSD symptoms being the most common type of mental health problem experienced.
From this study, it can be concluded that the extreme weather events related to climate change, and tropical cyclone exposure in particular, might lead to the onset or worsening of mental health problems for millions of people, particularly for those living in high-risk areas.
Strengths and limitations
The authors paid attention to both the individual and the societal level, focusing on understanding and predicting the effects following extreme weather events in the coastal area of South Florida. To succeed in their research objectives, the authors matched datasets across different fields (environmental, social and psychological) to develop novel predictions on the impact of climate change among the observed population. The results highlight the substantial environmental consequences of specific weather events, and showcase the need to replicate research in different coastal parts of the world that could be affected.
Nonetheless, the findings were different depending on the tropical cyclone dataset used, which could also indicate that we should interpret the results with caution. Another limitation was that the study only explored prediction in the location of South Florida. The projections made in the study would potentially only be relevant for the specific region due to the weather data. The weather data in other areas could look very different, as well as the negative effects of climate change. Additionally, we cannot be sure whether the mental health outcomes predicted were solely due to the effects of tropical storms. For example, as a result of the natural disasters, people may lose their house or be impoverished. Therefore, causality is not proved, as other social factors could influence the presentation of depression or anxiety. Lastly, the study showed a number of unexpected results, such as better physical health correlated with greater risk of mental health symptoms. Although the authors do not explain this, it could potentially be due to measurement errors.
Implications for practice
This is another study on climate change to raise awareness, and underline the urgency of multi-level strategies to address the psychological adverse effects. It is expected that extreme weather events will only increase in the coming years, as the temperature is expected to rise (IPCC, 2022). The mitigation of the climate crisis is not a one-man-job; it’s everyone’s responsibility. In this section, we purposefully do not focus solely on individual level actions, as to tackle climate change and its repercussions collective and community action is crucial.
What can mental health practitioners do?
It’s not surprising that climate change is in many people’s minds. Specifically, young people seem to be more likely to experience mental health distress due to the climate crisis (Scibberas & Fernando, 2021; Diffey et al., 2022). On a therapeutic level, it’s important for mental health practitioners to validate people’s fears, and offer a safe space to explore the distress. Change is always unsettling and people may feel uncertain. Fear can be paralysing, yet to bring action we need to overcome the anxiety around climate change. Psychological support to frontline activists and people working in sustainability is also essential, as often they may experience psychological and physical burnout (Butt et al., 2019). As Huxley & Lambrick (2022) point out:
We need psychological resources to approach the unknown, and to balance familiar against unfamiliar risks. Helping people to acknowledge, accept, and come to terms with the fact that change is coming is essential.
Moreover, clinicians should be aware of organisations and supportive outlets to encourage connection and signpost interested clients. On an organisational level, discussions could be encouraged among professionals to share knowledge and create collective goals. Research in clinical settings, such as the NHS, can take place to identify the prevalence of mental health distress related with climate change among the service users.
What can researchers do?
Rigorous research can lead to targeted evidence-based preventative strategies and effective interventions. Researchers need to keep building the literature and aim to understand the impact of singular events, e.g. specific natural disasters, but also explore the impact of climate change on mental health across the lifespan. It’s also important to note that countries are affected by the climate crisis in different ways, and thus will respond to these events in non-identical ways. Hence, international collaborations and research on a global scale is more important than ever to identify the impact and tackle the difficulties together. We need to consider that vulnerability is increased in low- and middle-income settings, with populations being greatly affected (Palinkas & Wong, 2020). Unsurprisingly, funding and commissioning research beyond the West is profoundly needed. Lastly, further qualitative and quantitative research may also indicate ways to develop targeted psychosocial interventions and understand in-depth individual and collective distress. As a result, clinicians would be able, led by evidence, to identify novel, creative and community-based ways to aid managing fear, anxiety and depression linked with climate change.
What can we do at a public health level?
The effects of climate change reach beyond the physical consequences for humans, affecting our psychological well-being. Currently, little is done tackling the consequences of climate change in public mental health, or taking effective steps to prevent negative mental health outcomes and reduced quality of life. For example, Fox and colleagues (2019) indicated that the public health response to climate change has been promising in monitoring climate hazards, diagnosing health status, assessing vulnerability, but less has been done to mobilise partnerships, mitigation and adaptation activities, communication, workforce development and evaluation. To ensure all core functions of public health are integrated into policy and planning, more needs to be done.
- Where does action start? It’s a good opportunity to reflect on individual and/or community action and answer the important question of where do we start? Build your own Venn diagram focusing your joy, solution and magic circle to identify feasible actions.
- Connect with like-minded people: Planetary Health Alliance, Climate Access, Climate and Migration Coalition.
- Read more opinion pieces and special issues on climate change research: Association of Clinical Psychologists UK Statement, Psychology and the Environmental Crisis (European Psychologist), Clinical Psychology Forum.
Statement of interests
Monsour, M., Clarke-Rubright, E., Lieberman-Cribbin, W., Timmins, C., Taioli, E., Schwartz, R. M., Corley, S. S., Laucis, A. M., & Morey, R. A. (2022). The impact of climate change on the prevalence of mental illness symptoms. Journal of Affective Disorders, 300, 430–440. https://doi.org/10.1016/j.jad.2021.12.124
Doherty TJ, Clayton S. The psychological impacts of global climate change. Am Psychol. 2011 May-Jun;66(4):265-76. doi: 10.1037/a0023141. PMID: 21553952.
Arman, N., Salam Shaoli, S., & Hossain, S. (2022). Mental health and climate change in Bangladesh. International Review of Psychiatry, 34(5), 513–515. https://doi.org/10.1080/09540261.2022.2093100
Berry, H.L., Bowen, K. & Kjellstrom, T. Climate change and mental health: a causal pathways framework.Int J Public Health 55, 123–132 (2010). https://doi.org/10.1007/s00038-009-0112-0
Palinkas, L. A., & Wong, M. (2020). Global climate change and mental health. Current Opinion in Psychology, 32, 12–16. https://doi.org/10.1016/j.copsyc.2019.06.023
Butt, N., Lambrick, F., Menton, M. et al.The supply chain of violence. Nat Sustain2, 742–747 (2019). https://doi.org/10.1038/s41893-019-0349-4
Huxley, R. & Lambrick, F. (2020). What do sustainability professionals and activists want from psychology? Clinical Psychology Forum.
Fox, M., Zuidema, C., Bauman, B., Burke, T., & Sheehan, M. (2019). Integrating Public Health into Climate Change Policy and Planning: State of Practice Update. International Journal of Environmental Research and Public Health, 16(18), 3232. https://doi.org/10.3390/ijerph16183232
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