The midnight sun shines over the ice-covered water near Resolute Bay, Nunavut. Swedish researchers suggest there is a link between round-the-clock summer sunlight and Greenland's high rate of suicide. (Jonathan Hayward/Canadian Press)

Researchers in Sweden say there might be a link between constant summer sunlight and a high rate of suicide in Greenland, a finding that medical officials in northern Canada are watching.

A team led by psychiatrist Karin Sparring Björkstén of the Karolinska Institutet looked at the seasonal variation of suicides throughout Greenland between 1968 and 2002.

The team's findings, published in the journal BMC Psychiatry on Friday, found an increase in the number of suicides during the summer months in Greenland, with a peak in June.

Björkstén told CBC News she was surprised by the findings, but believes the sunlight could be amplifying underlying mental health issues and other problems.

"There are, of course, many reasons that people commit suicide. But in the summer, when you don't sleep for extended periods of time, or you sleep very little, you may lose judgment," she said.

"Some people actually become manic or delirious and they really don't know what they are doing. Perhaps they didn't intend to commit suicide."

In the north of the Arctic island, Björkstén said 82 per cent of suicides occurred during the long periods of 24-hour summer light.

Björkstén's team also suggested that light-generated imbalances could lead to increased impulsiveness.

Suicides more common in summer among Nunavut women

The study bucks the common notion that most suicides take place during winter, when there are long stretches of darkness in the North.

In northern Canada, statistics show that more women in Nunavut commit suicide during the summer months, territorial chief coroner Tim Neily said.

But Neily said Nunavut men are most likely to commit suicide during the spring, when days are getting longer, and during the fall.

There have been 275 reported suicides in Nunavut, which has a population of about 29,500, since it became a territory in 1999.

Neily said the Swedish study and other research could help medical officials better understand what causes so many northerners to commit suicide.

"And then of course, once we have a pretty good understanding of why, then we're a big step towards 'let's solve the problem,''' he said.