As government representatives meet at the COP29 international climate summit in Azerbaijan, the… must be an urgent priority.
As psychiatrists who work with children and adolescents, we are so concerned that we are sharing our research at the Summit on the link between higher temperatures and suicidal thoughts and behaviors.
Our recent research shows that in warmer weather, young people are more likely to present to the emergency department due to suicidal thoughts and behavior.
Here's what we found and why one of us (Cybele Dey) is presenting our findings at COP29.
Mental health is getting worse
Young people and all over the world. There is growing evidence that inadequate climate change action is contributing to this. But it goes beyond young people worrying about the consequences of climate change for their future.
Climate change is a reality and its effects are already damaging the mental health of young people.
Extreme weather events – such as Australia's devastating Black Summer bushfires in 2019 and storms and floods since – are disrupting children's education, forcing displacement and causing trauma, fear and stress.
Our research reveals another, less discussed dimension.
The risk of suicidal behavior increases with warmer weather
Small increases in average temperature can mean a large increase in the number of warm days per year. For example, in 2019, Australia had 33 days with an average temperature above 39°C – more than the total for the previous 59 years.
Although research has shown a link between hot weather and suicidal thoughts and behavior in adults, little research has been done on this issue among young people.
Since suicide is a major health problem for young people – it is the leading cause of death for Australians aged 15 to 24 – we wanted to investigate this link.
Our recent study looked at all emergency department presentations in NSW for suicidal thoughts and behavior by people aged 12 to 24 years, during the warmer months (November to March) between January 2012 and December 2019.
We looked at these warmer months to focus on daily average temperatures and heat waves, rather than comparing between seasons.
We found that for every 1°C increase in average daily temperature, youth emergency room visits due to suicidal thoughts and behavior increased by 1.3 percent. For example, presentations on days with an average temperature of 30°C were 11 percent higher than on days with an average temperature of 21.9°C.
Risks also increased significantly even on days with average temperatures (not extreme heat), compared to mild, cool days during the warmer months.
A study like this can only show a link between heat and suicidal thoughts and behavior, rather than a direct cause. But the relationship was very strong. This means that there was a steady and predictable deterioration as the ambient temperature increased.
We also analyzed heat waves, that is, three or more very hot days in a row. Interestingly, presentations increased as much on the first warm day as on later days of a heat wave. That means every hot day is just as bad as the next.
Heat and inequality
Our research also found that young people in regions with some of Australia's most deprived suburbs were at greater risk of being in an emergency situation due to suicidal thoughts and behaviors than young people in more advantaged areas, even at the same temperature.
This is important because previous research has shown that socioeconomic disadvantage in itself does not increase the risk of suicidal thoughts and behavior in young people.
But a downside can mean that people are more vulnerable to the damage of hot weather. This could be due to, for example, a lack of cool shelter or the inability to pay for air conditioning or other cooling, as well as a lack of transportation and access to trees and water.
Complex interactions for mental health
Understanding the effects of climate change on mental health means examining complex interactions among multiple factors, and over time. Simple, linear 'cause-and-effect' models do not capture this.
Concerns about climate change also play a role in young people's mental health. But children and teens who exhibit high levels of anxiety may be expressing a healthy response to an unhealthy reality, rather than a mental disorder.
Inadequate action and dismissive responses from those in authority, including governments, exacerbate their distress.
What we are going to tell COP29
At COP29, leaders must understand that the mental health of young people is already being seriously affected by insufficient action on climate change, from increasing extreme weather events, heat, forced migration and disruption to school, work and healthcare.
High-income countries such as Australia must transition quickly and equitably to fossil fuels, including gas, in line with scientific evidence to reduce climate problems now.
Our research suggests this could help reduce youth suicide and suicidal thoughts and behaviors, and improve mental health more broadly.
How can we adapt?
If we are to adapt to climate change, we must prepare the mental health system at national, state, and local levels.
Public health messages about heat should also take into account the risks of a few warm days, and not just heat waves. It should be aimed at young people and include information on both mental and physical health.
This information should also be part of how health professionals are trained.
The current National Health and Climate Strategy includes two recommendations on mental health, focusing on community resilience and building a workforce trained in climate change and mental health. These must be translated from policy into action.
Sensible public health measures – such as improving rental standards and equipping bus shelters to withstand extreme heat – are needed now.
We must plan for an increase in mental health needs, including access to primary mental health care and evidence-based, local and culturally appropriate treatments for children and youth.