Hi gargazons,
Thank you for an interesting question and for accepting my findings as
the answer. I've added an additional study "Weather Forecasting as a
Public Health Tool".
Guardian Unlimited - Blame it on the sunshine By Emma Brockes and Oliver Burkeman
http://www.guardian.co.uk/weather/Story/0,2763,498326,00.html
"The sun is out and everyone is filled with the joys of summer:
relaxed, amorous and free spirited. Wrong. The truth is that warm
weather makes us irritable, violent and depressed."
[edit]
"In summer, of course, there are naturally more people out on the
street; more alcohol is consumed and the opportunity for petty
disagreements to occur is amplified. But there is something more. Dr
Lance Workman, a psychologist at the University of Glamorgan, has made
a link between hot weather and the levels of serotonin released in the
brain, a side-effect of which can be heightened aggression. "Violent
crime and riots increase as temperatures rise," he has said. "The
majority of riots in the USA occur when the temperature increases to
between 27C and 32C. When the temperature goes over 32C, however,
riots level off and begin to fall because people become so hot they
can't be bothered."
In London, where temperatures rarely make it into the lethargic 30s,
the murder rate peaks in the summer months. It is a trend reflected
worldwide: in the sweltering summer of 1988, the murder rate in New
York jumped by 75%. The connection between heat and violence has a
venerable history. In 18th-century Italy, the effect of the sirocco -
the hot, humid wind that sweeps annually through the Meditteranean -
was thought to have such a distorting effect on human judgment that it
was considered a mitigating circumstance when cited in court.
Dr Richard Michael, an American psychiatrist, has spent years studying
the effect temperature has on the crime statistics. In the 1980s, he
analysed 27,000 instances of women being abused by their live-in male
partners, in accounts provided by refuge organisations. His findings
were startling.
"The frequency of abuse is closely related to annual changes in
ambient temperature," he concluded in his 1986 paper, An Annual Rhythm
in Battering of Women."Violence by men toward women increases in
summer independently of any major seasonal changes in the opportunity
for contact between perpetrator and victim." In a 1983 study, the US
National Institute of Mental Health analysed 50,000 rapes in 16
locations. July and August were the peak months in all cases.
Statistics alone, however, are a weak indicator of cause and effect,
which are easier to prove in a laboratory. Ehor Boyanowsky, a
criminologist at Simon Fraser University in Canada, has spent 30 years
researching the effects of heat on the brain. Having noticed that most
of the US race riots in 1967 occurred on days with temperatures
greater than 27C, he designed a series of extraordinary laboratory
tests that persuaded him of the connection between heat and extreme
behaviour.
In one test, a set of volunteers was subjected by a researcher to a
series either of insults or compliments. The volunteers were invited
to retaliate by administering electric shocks. Those volunteers held
in temperatures of 24C reacted aggressively when insulted and
delivered the shocks; those in temperatures of 33C-35C were so
aggravated that they administered shocks even when the researcher was
complimenting them. Differences "of formal civility and higher
violence rates in the southern states versus greater bluntness and
lower violence rates in the north have been observed", he notes.
Global warming, he warns, could make the problem even worse.
Far away from the riots and the homicides, the heat still gets to us,
stoking politely suppressed emotions into flames - and nowhere is this
more true than in the urban furnace of the traffic jam. In 1986, two
psychologists, Douglas Kenrick and SW Macfarlane, devised an
experiment few might have dared conduct on a clogged British A-road in
recent days.
In a range of weather conditions, they arranged for a car to pull up
repeatedly at a set of traffic lights and refuse to budge when they
turned green. As frustration crackled through the vehicles stacking up
behind, they got out their clipboards and measured how much time
elapsed until another driver sounded their horn, and how many times
they did so. They found a direct, linear relationship between the
temperature outside and the intensity and alacrity of horn-honking.
Only 10% of British cars feature air-conditioning; the rest of us boil
and honk.
"On the roads during the summer you get that classic mix of leisure
motorists and people still working, giving rise to a scenario where
the casual driver is pootling along to Stonehenge and someone behind
him is late for a business meeting," says Rebecca Rees, a spokeswoman
for the AA. Perhaps partly as a result of the frustration thus
generated, the number of car users killed on British roads rises
steadily between April (115 last year) and August (127). Similar
situations occur in other countries where the heat comes as a
disorienting surprise. One psychologist at Uppsala University in
Sweden, AE af Wahlberg, found a greater tendency for Swedish buses to
crash on hot days. There was more going on, he suggested, than the
mere fact that the sun brings more people out onto the roads.
The link between rising temperatures and general irritability is
compounded by dehydration - most of us never drink enough water
anyway, but it only becomes evident in hot weather - made worse by
overheated offices or air-conditioning systems, which can cause
sweltering workers to lose the equivalent of 10 glasses of water a
day. Of course, we quench thirst in other ways, too - one of several
reasons why public drunkenness, and the crimes associated with it,
spiral in hot weather: last year, in London, there were 1,000 more
instances of common assault - often linked to alcohol - in July than
in January. Adding to the oppressive atmosphere, psychologists have
identified a phenomenon they call "summer depression", the opposite of
ordinary seasonal affective disorder, brought on by the fading light
of winter.
These are not problems that we, as a nation, are accustomed to
confronting, conditioned as we to cold-weather complaints. If there
are temperature-based ills to be suffered, they are, we imagine, the
colds, chill blanes and sour expressions for which our water-logged
country is renowned. But after the events of this week - when, in the
heat of a summer night, deeply felt tensions in Oldham ignited into
violence, we might be advised to think again."
=========
Maharishi Ayurveda
http://www.mapi.com/en/newsletters/ayurveda_summer_cool.html
"It might be hard to believe that an ordinary thing like hot weather
can affect our mood that much, but in fact, the effects of hot weather
even show up in the nation's crime statistics. For example, data from
the Des Moines, Iowa Police department show that more violent crimes
are committed during the summer than during the winter."
=========
bbc.co.uk - Weather and Behavior
http://www.bbc.co.uk/weather/features/health_culture/behaviour.shtml
"In heatwaves, where the temperature is significantly higher than
expected for the time of year, people tend to behave more
irrationally. New York City sees regular summer crime waves, which are
believed to be as a result of the hot weather."
=========
Permanent Peace - Effect on Crime
http://permanentpeace.org/benefits/crime.html
"Although violent crime had been steadily increasing during the first
five months of the year, and although violent crime usually peaks in
the hot weather months, soon after the start of the study, and during
a near-record summer heat wave, violent crime began decreasing and
continued to drop until the end of the experiment (maximum decrease
23.6%), after which it began to rise again. The likelihood that this
result could be attributed to chance variation in crime levels was
less than two parts per billion (p < .000000002). The drop in crime
could not be attributed to other possible causes, including prior
causative factors, temperature, precipitation, weekends, and police
and community anti-crime activities."
=========
bbc.co.uk - Weather and Depression
http://www.bbc.co.uk/weather/weatherwise/living/effects/morale.shtml
"Serious mental conditions such as schizophrenia and manic depression
are said to worsen with changes in the weather, and suicide rates are
affected too. Hot weather is also linked with higher levels of street
violence and attacks, as well as rioting and unrest. The hot dry Fohn
and Scirocco winds are said to damage the health - in Germany the
accident, crime and suicide rates rise during the Fohn, whilst the
Scirocco is said to cause madness."
=========
HARVARD GAZETTE ARCHIVES - Tracking the trends of criminal activity
http://www.news.harvard.edu/gazette/2005/03.03/06-crime.html
"The authors examined suspected correlations between crime trends and
weather, relying on the knowledge that heat waves often lead to an
increase in crime in the short run while severe rain or snowstorms
generally decrease crime. They found that crime was systematically
lower than normal in weeks following periods with hotter temperatures
(during which crime typically increased)."
=========
77th street area - Crime Trends
http://www.lapdonline.org/community/basic_car_newsletters/12_77th.htm
"The recent heat wave within the City of Los Angeles has not only
applied to the weather. The Hyde Park district has experienced a spike
in crime, which seemingly began around the same time the summer season
began. The neighborhood gang has been the primary cause for the
increase."
=========
Weather Forecasting as a Public Health Tool
Sara Hughes*, Mark A Bellis*, William Bird# and John R Ashton§
http://www.nwph.net/Regional%20Documents/Weather.pdf
[Page 3]
"High ambient temperatures see:
? Elevated levels of suicide.
? An increase in the rate of violent crime such as assaults and
domestic violence."
[edit]
[Page 17]
"2.3 Violent crime
Variations in ambient temperature can affect the level of violent
crimes seen in the community. Rates of assaults (e.g. Rotton and Cohn,
2000), domestic violence (e.g.Cohn, 1993), and collective violence5
(Carlsmith and Anderson, 1979) have all been reported to increase
during hot weather.
These rises, at least in part, may be related to rises in alcohol
consumption during high temperatures, as alcohol intoxication
increases a person?s likelihood of being both a perpetrator and victim
of aggression and violence (McClelland and Teplin, 2001). Thus, the
relationship
between temperature and violent crime is dependent on temporal factors
such as time of day, day of week and season (Cohn and Rotton, 2000),
with the relationship between temperature and assault being strongest
during the evening hours and weekends (Cohn and Rotton, 1997). High
temperatures may also have a direct influence on violence by
increasing feelings of hostility and aggressive attitudes and beliefs,
which reduce a person?s tolerance for annoyances (Anderson, 2001).
In general, the application of weather forecasts to alleviate problems
of violent crime has been relatively unexplored. However, heat
warnings may be useful to police services as well as health services
to predict increases in violent behaviour especially over weekends or
holiday periods. Thus, in both health and judicial settings,
meteorological data can help plan what interventions are required,
where pressures on systems will develop, and how staffing levels might
be managed to accommodate busy periods."
=========
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=========
Best regards,
tlspiegel |