Re: What kind of effects does weather have on your emotions?

Hi Rachel-Marie :)

You're right, it is difficult to find much information about this!  I hope 
this reaches you in time and answers your questions.

The most well-known effect of weather on mood is a medical condition called 
Seasonal Affective Disorder (SAD for short).  People who suffer from SAD 
get very tired and depressed during the winter months.  Actually it is less 
to do with the weather - more because during the winter, days are very 
short and people don't see so much daylight (especially if they spend most 
of the day in a schoolroom or office!).  Of course, the further North of 
the equator you live, the shorter the days during winter  and the more 
likely you are to have symptoms of SAD(1).
 
When you are exposed to sunlight, your body makes lots of Vitamin D3, and 
because of that you make more of a substance called Serotonin (pronounced 
Ser-ah-TONE-in).  Serotonin is a chemical found in the brain and it's very 
important to your mood.  We know that if you don't have enough of it then 
you can become depressed - antidepressant drugs like Prozac work because 
they increase the amount of serotonin available to the brain.  Scientists 
think that some people aren't so good at making their own serotonin (2), 
and need more sunlight than other people to do it properly.  These are the 
people who suffer from SAD during the winter, because they just can't get 
enough sunlight during the short days to make all the serotonin they need 
to stay happy.  This is probably down to their genes (chemical instructions 
which map out your whole body's biology, from what colour hair you have to 
how likely you are to get heart disease); SAD quite often runs in families. 
  

Experiments have shown that people with SAD can be helped by using a 
special "light box", a big plug-in light source that gives off the same 
kinds of light as the sun (but without the harmful ultra-violet (UV) rays 
that can cause cancer).  You can work or read or just sit in front of these 
for some time each day and many people with SAD find it improves their 
mood.  It does just the same job as sunshine by making your body produce 
more Vitamin D3 and serotonin (but of course, it won't give you a suntan!). 
 One experiment (3) found that even people who didn't suffer from SAD felt 
happier and more positive during the winter if they had more Vitamin D in 
their diets.

Of course, SAD isn't the only way that your mood can be affected by 
weather.  Some experiments show that peoples' moods change depending on how 
ionised the air around them is.  Ionisation is what happens to the air 
before or during a storm.  One experiment (4) found that most people became 
more grouchy when exposed to positive ions in the atmosphere.  Another (5) 
showed that people experienced emotion (good or bad, depending on what was 
happening to them) more intensely when the air was like that.  If you 
compare police records with weather records it can be shown that automobile 
accidents, crimes and suicides all happen more often in that kind of 
weather.  

Sunny weather can cause mood problems for people too.  People with an 
allergy to pollen (hay fever) are more unhappy in summer (when pollen 
levels are highest) than people who don't have hay fever (6) - and it can 
make them learn slower and find decision-making harder, too.  Another 
problem with the heat is that it can make some people more aggressive - but 
one study found that a cooling drink could calm them down (7).

I hope this helps but feel free to email me on tinyclanger@bigfoot.com if 
you have any more questions.  Good luck in your science fair!  

Chris.


References:

(1) Rosen LN. Rosenthal NE. 
Seasonal variations in mood and behavior in the general population: a
factor-analytic approach.
Psychiatry Research. 38(3):271-83, 1991 Sep.

(2) Graw P. Recker S. Sand L. Krauchi K. Wirz-Justice A. 
Winter and summer outdoor light exposure in women with and without seasonal
affective disorder.
Journal of Affective Disorders. 56(2-3):163-9, 1999 Dec.

(3) Lansdowne AT. Provost SC. 
Vitamin D3 enhances mood in healthy subjects during winter.
Psychopharmacology. 135(4):319-23, 1998 Feb.

(4) Charry JM. Hawkinshire FB 5th. 
Effects of atmospheric electricity on some substrates of disordered social
behavior.
Journal of Personality & Social Psychology. 41(1):185-97, 1981 Jul.

(5) Baron RA. Russell GW. Arms RL. 
Negative ions and behavior: impact on mood, memory, and aggression among 
type
A and type B persons.
Journal of Personality & Social Psychology. 48(3):746-54, 1985 Mar.

(6) Marshall PS. Colon EA. 
Effects of allergy season on mood and cognitive function.
Annals of Allergy. 71(3):251-8, 1993 Sep.

(7) Baron RA. Bell PA. 
Aggression and heat: the influence of ambient temperature,
negative affect, and a cooling drink on physical aggression.
Journal of Personality & Social Psychology. 33(3):245-55, 1976 Mar.