Fischer Ranacher Sticher 2025

Blues, depression, and anxiety the question “Do you often have negative feelings such as having the blues, being desperate, suffering from anxiety or depression, if 0 means “never” and 10 “always”?” was based on the Positive and Negative Affect Schedule.

In this study, one of the questions researchers asked people was about their negative feelings, like feeling blue, depression, anxiety, or desperation. Participants rated these feelings in a self-report questionnaire that measures both positive and negative emotional states. If a participant gave zero, it means they never experienced that feelings at all, and when a rating is 10, it means they always struggle with those negative thoughts.

Given that the average cold season temperatures in Switzerland are between − 10 and + 25 degrees Celsius, we hypothesised a negative association between air temperature in the autumn and winter months and stress, loneliness, anger, sadness, worry, blues, depression, and anxiety, and a positive association between air temperature and joy, optimism, strength, energy, and general life satisfaction.

The authors explain that during the cold season in Switzerland, temperatures usually range from about −10 to +25 degrees Celsius. Based on this, they expected that colder weather in autumn and winter would be linked to more negative emotions. At the same time, they believed that warmer temperatures during these months would be connected to more positive feelings.

The analyses showed that both higher average temperatures over the past 14 days (ß=−0.151, p=.033) and over the past 30 days (ß=−0.238, p=.018; see also Fig. 1b) were associated with lower stress levels. These results were confirmed by bootstrapping, both for the 14-day (95% CI [−0.070, −0.002]) and for the 30-day time frame (95% CI [−0.112, −0.010]).

The results showed statistically that when the weather was a bit warmer than usual during the last two weeks or the last month, people reported less stress. This was true even after checking the results several times using more advanced statistical methods. So basically, in cold seasons, a short period of warmer temperatures helped reduce people’s stress levels.

Longitudinal studies combining high-resolution, spatially distributed meteorological data (e.g., via remote sensing or reanalysis datasets) with psychometrically sound measures of psychological well-being and mental health (e.g., disorders treated with selective serotonin reuptake inhibitors) are warranted to replicate our findings.

The authors suggest that future studies should follow people over a longer period of time and use very detailed weather information from many different locations. They also recommend using strong and reliable mental health measurements, for example data from people who are being treated for mood disorders with medications.

The study mainly focused only on air temperature, but in the cold months there are many other environmental changes happening at the same time. For example, the days get shorter, there is less sunlight, and we see more cloudy skies, and all of these can influence our mood, stress, and how satisfied we feel with our life. Another idea for future research could be to look at the opposite situation, like in the warmer seasons, and see if suddenly colder weather in spring or summer is connected to higher stress or more loneliness. I feel that including these extra factors would make it easier to understand if temperature alone is causing the mental health changes, or if it actually works together with sunlight and other conditions in the winter.

The hardest part was understanding the complicated statistical models, especially the polynomial regression and the lagged temperature effects. It took me a while to understand why the temperature from two weeks ago could influence someone’s current stress level. Also, the introduction had many references to climate science and public health that felt a bit too advanced for me. But even with these challenges, the main message of the paper was very clear.