(Ruth Klinkhammer/AINA via Medical News Today, 20 April 2010) -- Inuit preschoolers in Nunavut are as tall as their U.S. counterparts but they're also heavier, according to a new study published in the online edition of the International Journal of Circumpolar Health. This represents a remarkable change from previous work showing Inuit infants began life with equivalent birth lengths, but were falling behind by the time they were six months old.

"This is in many ways a good news story," says Dr. Tracey Galloway, lead author and a Post-doctoral Fellow at the University of Toronto's Dalla Lana School of Public Health. "Height reflects overall health status over a lifetime and over generations."

Unlike weight, which can fluctuate quickly, it takes decades for changes in health to be reflected in the height of a population. Factors influencing height include nutrition of the child, maternal health and diet, and infectious disease rates. However, says Galloway, it's impossible to know whether this trend will continue because school-aged children and youth have not been recently surveyed. The study of 26% of three- to five-year-olds in 16 Nunavut communities marks the first time data on the height and weight of preschoolers has been collected for Inuit populations living in the North.

The data are from the International Polar Year Nunavut Inuit Child Health Survey led by McGill University, the University of Toronto and territorial and community partners.

Tagged: Arctic, News, Polar research: Reports and findings

(University of Washington press release via EurekAlert, 28 April 2010) -- New research indicates that one of the largest fresh-water floods in Earth's history happened about 17,000 years ago and inundated a large area of Alaska that is now occupied in part by the city of Wasilla, widely known because of the 2008 presidential campaign. The event was one of at least four "megafloods" as Glacial Lake Atna breached ice dams and discharged water. The lake covered more than 3,500 square miles in the Copper River Basin northeast of Anchorage and Wasilla.

The megaflood that covered the Wasilla region released as much as 1,400 cubic kilometers, or 336 cubic miles, of water, enough to cover an area the size of Washington, D.C., to a depth of nearly 5 miles. That water volume drained from the lake in about a week and, at such great velocity, formed dunes higher than 110 feet, with at least a half-mile between crests. The dunes appear on topographical maps but today are covered by roads, buildings and other development.

"Your mind doesn't get around dunes of that size. Obviously the water had to be very deep to form them," said Michael Wiedmer, an Anchorage native who is pursuing graduate studies in forest resources at the University of Washington.

Wiedmer is the lead author of a paper describing the Wasilla-area megaflood, published in the May edition of the journal Quaternary Research. Co-authors are David R. Montgomery and Alan Gillespie, UW professors of Earth and space sciences, and Harvey Greenberg, a computer specialist in that department.

By definition, a megaflood has a flow of at least 1 million cubic meters of water per second (a cubic meter is about 264 gallons). The largest known fresh-water flood, at about 17 million cubic meters per second, originated in Glacial Lake Missoula in Montana and was one of a series of cataclysmic floods that formed the Channeled Scablands of eastern Washington. The megaflood from Glacial Lake Atna down what is now the Matanuska River to the Wasilla region might have had a flow of about 3 million cubic meters per second. Another suspected Atna megaflood along a different course to the Wasilla region, down the Susitna River, might have had a flow of about 11 million cubic meters per second. The researchers also found evidence for two smaller Atna megafloods, down the Tok and Copper rivers.

Tagged: Arctic, News, Polar research: Reports and findings