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Alaska's year without summer



Two hundred and thirty years ago, when General George Washington marched back to New York City as British troops left the house, a volcano erupted in Iceland.

For eight months in 1783, the Laki volcano spewed lava and burped harmful fumes in the atmosphere. A quarter of Iceland's inhabitants died, and the sulfur-containing gases that spread worldwide reflected the sun's rays and made many places on Earth cooler.

With evidence kept in white spruce, researchers believe that the Laki outbreak was a disaster for Northwestern Alaskans who had no idea why their July became November.

Rosanne D & # 39; Arrigo from the Tree Ring Laboratory at the Lamont-Doherty Earth Observatory in New York recently recounted the story of Alaska's Year Without a Summer. She attended the fall meeting of the American Geophysical Union last month in Washington, DC

. On a poster in a cavernous assembly room there she showed a photo of tree rings from a white spruce from Alaska. In the midst of a series of dark lines stands a faint line, which dates back to 1783.

Tree rings are thick-walled cells that form in conifers late in the growing season. The unmistakable tree ring in D & # 39; Arrigo's example shows a highly unusual year, 1783, in the midst of a century-long spruce growth.

D & Arrigo, Alaska's archaeologist Karen Workman and the late Gordon Jacoby once wrote of a "catastrophe" for the northwestern Alaska Inuit caused by the Laki outbreak and the subsequent cold temperatures. The scientists largely based their conclusion on wood cores that were grown from white spruce trees on the northern tree line.

Alaska archaeologist and adventurer James Louis Giddings. Photo courtesy of John Christeson.

James Louis Giddings collected many of these plugs.

In June 1940, Giddings, a UAF-trained archaeologist and mining engineer, flew from Fairbanks to Allakaket. Arrived at this small village, he aimed his compass on a mountain pass over the Koyukuk, which led him to the upper reaches of the Kobuk.

Giddings started to run. He had a 40-pound pack and a 0.22 rifle with him, along with "a change of heavy underwear that must be worn as a mosquito repellent."

When he reached the Kobuk River, he collapsed a raft. He swam his length, took tree pips and stopped at known and possible archaeological sites.

He turned right at the Kobuk Estuary and headed up the Noatak River. When Giddings had finished there, he went to the Seward peninsula and ended his scientific journey only when he arrived in the city of Haycock, not far from the present village Koyuk.

In the fall of 1940, Giddings wrote his master's thesis:

Half a century later, Lamont-Doherty scientists used some of Gidding's samples. With records from Giddings and others in Alaska and the weather station's real data collected at the University of Alaska and elsewhere, researchers reconstructed the summer temperatures of Alaska from the late 17th century to the present day.

They reported average temperatures in Alaska From May to August most of the time was about 53 degrees Fahrenheit. In 1783, the average temperature between May and August was about 44 degrees.

"This anomaly is off the charts," said D & # 39; Arrigo.

To further demonstrate the madness of 1783, Lamont-Doherty's scientists also cite a book on oral traditions of natives from northwest Alaska, written by William Oquilluk.

In this book, Oquilluk describes four ancient legends, all related to the extinction of all humans living in northwestern Alaska. The first two events were too far away for the researchers to imagine what they might be. The fourth and most recent disaster was the 1918 influenza epidemic that hit Alaska and the rest of the world so hard.

Researchers argued that the third disaster in northwest Alaska is related to the island of Iceland. Oquilluk wrote about it as "The time summer time did not come."

In that year (perhaps 1783) migratory birds had returned to Alaska in the spring and everything seemed to be normal until June was over. Then "it suddenly became cold weather. , , and people "could not hunt and fish," wrote Oquilluk.

"In a few days, the recently thawed lakes and rivers froze. The warm weather returned only in the spring (early April) of the next year, "write the scientists of Lamont-Doherty in their 1999 work.

Since the late 1970s, the Geophysical Institute of the University of Alaska has Fairbanks This column is provided free of charge in collaboration with the UAF Research Community. Ned Rozell is the scientific author of the Geophysical Institute.


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