People are easily affected by change in the weather. There is a little range in temperatures that people appreciate, higher or lower temperatures will quickly affect the mood negatively. Some sicknesses are affected by the weather, for example: seasonal affective disorder, also called winter depression.
One insightful 2008 study found that good weather has a greater effect on boosting a person’s negative mood than on a positive one, with negative moods being improved on days where the weather was good, but with no effect on people who were already feeling positive.
One important finding is that our immediate mood (momentary happiness) is more affected by the weather compared to our general well-being. A German study in 1983 called people on rainy and sunny days to ask about their current mood and their general well-being. Participants reported higher levels of momentary happiness on days when it was sunny, while on rainy days how people felt was found to be lower.
A more recent 2013 study found that people surveyed on exceptionally sunny days indicated higher life satisfaction than respondents interviewed on days with “ordinary” weather. While these feelings appear to be fleeting and variable from day to day, it suggests that good weather may also affect our overall mood.
One study in 1979 noted that good weather could affect mood through symbolic associations. To put it simply, good weather “could increase mood by stimulating thoughts of swimming, picnics, and other outings, whereas cloudy days could be associated with the disappointment of canceled plans and the annoyance of rain and snow.”
Vitamin D deficiency has even been linked to depression. Vitamin D is a unique and necessary vitamin and many people simply aren’t getting enough of it. With only a handful of foods containing any traces of this essential vitamin, the only way to get enough vitamin D is through adequate exposure to sunlight, hence its nickname of “the sunshine vitamin.”
Comprehensive research on this very subject was done by Canadian researchers, who reviewed 14 studies, consisting of 31,424 participants, and demonstrated that there is a strong correlation between depression and a lack of vitamin D; the lower the vitamin D level, the greater the chance of a person having depression. Several studies have also shown sunlight to markedly improve mood, similar to the aforementioned findings of light exposure decreasing depressive symptoms.
Even though the weather can help lift our mood, relying on good weather for our happiness is not sufficient and reliable.