Medieval Records Confirm Global Warming

W A S H I N G T O N, Sept. 7 -- River captains long dead,15th-century Japanese priests, and records kept by Swissbelievers who liked to carry a statue of the Madonna across afrozen lake confirm that global warming is a real trend,scientists said today.

An international team of researchers has pieced togetherrecords kept from as far back as 1443 to show that temperaturesare not only rising — they are changing the way lakes andrivers freeze in the Northern Hemisphere.

“The thing that makes this catchy is that this is a verysimple way of looking at what happened over the last 150years,” said John Magnuson of the University of Wisconsin inMadison, who led the study.

Many studies conclude that global temperature took a suddenupward turn at around the turn of the last century — when theIndustrial Revolution reached its peak and people startedpumping so-called greenhouse gases into the atmosphere.

Holy People, Fur Traders

Climate records confirm a rise of at least 1 degree C (2degrees F) over the past century or so, and various computermodels show a consistent pattern.

But Magnuson and colleagues wanted to see what effect thiswarming pattern had on people.

“These are direct observations of people, five generationsof people,” said Magnuson, who specializes in the study offreshwater bodies.

“Some were religious people, some were fur traders. Theyhave looked out and said ‘the lake, the bay, the river is opentoday.’”

For example, holy people of Japan’s Shinto religion keptcareful records at Lake Suwa, where deities from shrines oneither shore were believed to have used surface ice to visitback and forth.

At Lake Constance, on the border of Germany and Switzerland,congregations at two churches, one in each country, had atradition of carrying a Madonna figure back and forth across thelake when it froze.

Confirming El Niño

In Canada, the shipping and fur trade meant records of riverfreezing were kept as far back as the early 1700s.