It is a popular idea that weather affects our mood. The damp free and beautiful warm spring morning, the well welcomed breeze on a mild summer evening, the rustling hum of yellow and red leaves on the ground on an autumn afternoon, the dreams of a white Christmas where the glistening of the snow and ice somehow warms your heart. But these are positive affects of weather. All that April rain better bring amazing May flowers. The dropping pressure causes almost instant headache and the dampness makes my neck ache. Many people do not like the spring rain or the short days of winter, but how much does it really affect our moods and mental health?
According to a study I reviewed for my Psychology class October 28, 2008:
Denissen, J., Butalid, L., Penke, L., & Aken, M. (2008). The effects of weather on daily mood: A multilevel approach. Emotion, 8 (5), 662-667.
“Weather is widely believed to influence people’s mood” (p. 662). Most of us think the sunny side of the street is the place we want to be. Just the same, most of us would rather stay at home curled up on the couch when it’s cold and rainy outside. Four European scientists teamed up to build on past research already conducted on the relationship of weather and mood. Several past studies focused on people with SAD, seasonal affective disorder, and is believed that since these people experience such extreme manifestations to weather variation that it isn’t reflective of the general population. The other factor which these researchers feel elevates their study above others is the amount of weather parameters taken into account. Instead of one or two parameters, they will test for six: temperature, wind power, sunlight, precipitation, air pressure, and photoperiod.
Past studies show the effect of weather on mood is relatively small. However, because most of these studies were conducted in North America it is questioned whether demographic differences will exhibit different results on perceptions. The researchers predict they can use personality types to determine a person’s susceptibility to daily weather change. Individuals naturally vary in sensitivity to weather change but previous research has indicated that the trait of neuroticism in a person brings about a heightened sensitivity. It is also hypothesized that age decreases seasonal sensitivity and that women are affected by weather more so then men. “The aim of this exploratory approach is to get a further understanding of the possible relation between weather, personality, and mood” (p. 663).
The study included 1,233 Germans ranging in age from 13 to 68 years, and almost 89% of participants were women. Data was gathered by means of an online diary updated almost daily by each respondent. Before the study was initiated all participants filled out a lengthy personality survey which once their personality types were recognized could be compared to their responses to determine whether some personality types really are more easily influenced by weather.
Each diary entry included a questionnaire that measured the participant’s perception to whether that day’s weather had a positive or negative affect on their mood. Participants were given a list of adjectives to describe their mood and were asked to grade each one with a scale of 1 (“not at all”) to 5 (“very much”). The questionnaire measured positive affect using words like “active,” “enthusiastic,” “excited,” and “inspired.” Negative affect was measured by using words like “nervous,” “jittery,” “irritable,” and “distressed.” For both positive and negative affect measurements all words were scored by the participant each time they filled out the questionnaire. There was just a single question for tiredness which used the same 1 (“not at all”) to 5 (“very much”) scale. “The different scales of the daily questionnaires were presented in randomized order to avoid the development of automatic response sets” (p. 664). Taking into account each participant’s zip code address, all data collected from the online diaries was then matched to weather recorded by the German Weather Institute.
The results showed no significant affects of any of the six parameters on positive affects on mood. Both air pressure and precipitation had a negative affect on mood. Add in low sunlight and there was a significant increase in tiredness reported. The explanation given for this was that “vitamin D3, which is produced in skin exposed to the hormone of sunlight, has been found to change serotonin levels in the brain, which could account for the changes in mood” (p. 666). Because this experiment covered over 18 months of diary entries seasonal variation was also captured. The claim is that photoperiod, the length of day, affects mood negatively in the fall and winter months due to the shortening of daylight. The only time wind power had a significant negative affect on mood was in the springtime. The claim is that due to the lengthening of daylight and rise in temperature more people want to spend time outdoors and high wind power can curtail the enjoyment of the changing weather and cause more hassle.
The results showed great variation between individual susceptibility to mood changes due to weather. However, unlike the hypothesis age, gender, and personality were not found to be significant and the researchers “thus were unable to explain the individual differences in the affect of weather on mood” (p. 665-666).
Although the experiment took place over a year and a half period and the web-based data collection ensured access to a large population all across Germany, the researchers admit there were several limitations to their results. The unequal gender distribution was probably caused by the web-based collection methods, hypothesizing that with almost 90 percent female participants that perhaps males are not attracted to online questionnaires. Would a construction worker who is outside all day everyday be affected by weather the same way as an office worker? Probably the most important factor missed, was that the experiment “failed to assess the time that participants spent outside each day, which may have emerged as an important moderator of the effects of weather on mood” (p. 667).
Overall the results showed that your mood doesn’t get any better based on good weather; however, it can have a negative effect if the weather gets worse. Personality type, age and gender weren’t shown to have a significant affect on how we perceive our mood vs. weather. However, due to the limitations of the experiment the researchers admit that before the relationship between weather and mood can really be determined more studies need to be performed.
Vampires may just have a reason to be afraid of the light.
Suicide rates in Greenland increase during the summer, peaking in June. Researchers writing in the open access journal BMC Psychiatry speculate that insomnia caused by incessant daylight may be to blame.
Karin Sparring Björkstén from the Karolinska Institutet, Sweden, led a team of researchers who studied the seasonal variation of suicides in all of Greenland from 1968-2002. They found that there was a concentration of suicides in the summer months, and that this seasonal effect was especially pronounced in the North of the country – an area where the sun doesn’t set between the end of April and the end of August. Björkstén said, “In terms of seasonal light variation, Greenland is the most extreme human habitat. Greenland also has one of the highest suicide rates in the world. We found that suicides were almost exclusively violent and increased during periods of constant day. In the north of the country, 82% of the suicides occurred during the daylight months (including astronomical twilight)”.
The researchers found that most suicides occurred in young men and that violent methods, such as shooting, hanging and jumping, accounted for 95% of all suicides. No seasonal variation in alcohol consumption was found. The authors speculate that light-generated imbalances in turnover of the neurotransmitter serotonin may lead to increased impulsiveness that, in combination with lack of sleep, may explain the increased suicide rates in the summer. They said, “People living at high latitudes need extreme flexibility in light adaptation. During the long periods of constant light, it is crucial to keep some circadian rhythm to get enough sleep and sustain mental health. A weak serotonin system may cause difficulties in adaptation”.
Björkstén concludes, “Light is just one of many factors in the complex tragedy of suicide, but this study shows that there is a possible relationship between the two.”
Accentuation of suicides but not homicides with rising latitudes of Greenland in the sunny months
Karin S Björkstén, Daniel F Kripke and Peter Bjerregaard
BMC Psychiatry (in press)(from: http://www.medicalnewstoday.com/articles/149409.php)