For this study, researchers examined the mental health records of 2 million randomly selected USA citizens using data collected by the Centers for Disease Control and Prevention's Behavioral Risk Factor Surveillance System between 2002 and 2012, comparing the responses to meteorological and climatic data from the same period.
This study echoes (and builds upon) previous research that found an association between heat waves (which are expected to increase in frequency and intensity as a result of climate change) and increased hospital admissions for self-harm and other health concerns. This led research scientist at Massachusetts Institute of Technology, Nick Obradovich, to study the effects of climate change on issues such as depression, anxiety and stress.
Scientists picked all the information from climate econometrics to understand if there are any links between mental health and climatic conditions in the past.
Published Monday in the journal PNAS, the study looked at mental health issues and compared them to climate data in search of trends. He warned that a 2 degree Celsius rise can push human mental health over the edge.
Worldwide, it is estimated that one in five adolescents experience mental health challenges, though most remain under-diagnosed and untreated. The researchers found that women and people in the low-income demographic are more apt to develop mental health issues because of climate change, for example. Increase in evaporation also leads to more rain and storms they add.
The researchers extrapolated that over a 30-day period, a shift of monthly temperature from 25 to 30 degrees Celsius to greater than 30 degrees Celsius would produce 2 million individuals who suffer from mental health issues. "In that world, the effect between hot temperatures and mental-health outcomes might be reduced". They called for more studies in the "regions with less-temperate climates, insufficient resources, and a greater reliance on ecological systems" and predicted that these regions may have more "severe effects of climate change on mental health".
It also recommended investing in mental health resilience-building through parents and teachers; and psycho-social provision in schools and community spaces, especially in hardship contexts such as conflict and natural disaster settings.
WHO noted that "evidence is growing that promoting and protecting adolescent mental health benefits not just adolescents' health, in the short- and the long-term".