Posted on 02/28/2008 7:02:41 PM PST by blam
Drained lake holds record of ancient Alaska
By Ned Rozell
February 27, 2008
Not too long ago, a lake sprung a leak in the high country of the Wrangell-St. Elias Mountains. The lake drained away, as glacier-dammed lakes often do, but this lake was a bit different, and seems to be telling a story about a warmer Alaska.
The lake, known as Iceberg Lake to people in McCarthy, about 50 airmails to the north, had been part of the landscape for as long as people could remember. Pinched by glacial ice, the three-mile-long, one-mile-wide lake on the northern boundary of the Bagley Icefield was remote but notable enough that it was the cover photo for a recent book about hiking Wrangell-St. Elias National Park.
After holding water for centuries, Iceberg Lake in the Wrangell-St. Elias Mountains drained in 1999 and has lost its water every year since except 2001. Photo by Mike Loso.
When McCarthy guide Richard Villa visited the area with a client in the summer of 1999, he was stunned to see the lake, which had lost much of its water. Villa later told Mike Loso, a Kennicott resident part of the year and now a professor at Alaska Pacific University in Anchorage.
Loso flew to the lake the next summer with Bob Anderson and Dan Doak, scientists who also reside in McCarthy for part of the year. The men saw a muddy lakebed where Iceberg Lake had sat for so long. Streams of meltwater had cut though the mud, making sharp canyons. Loso, Anderson, and Doak hiked into the gullies and saw on the walls many layers of the former lake bottom. They knew that each two layers of sediment-a thinner layer of fine-grained deposits that settled in winter and coarser sand forced in with summer runoff-represented a year in the life of the lake.
"We eyeballed these layers and said 'Wow, there's at least 1,000 of these things,'" Loso said.
Scientists often pull plugs of sediment from the bottom of lakes to find an ancient record of pollen, dust, ash, and other things that have drifted, or flowed in over the years, but their records usually don't go back farther than the Little Ice Age, a cold period from about 1600 to 1850 when many glaciers advanced. Those glaciers plowed over most of the landscape, but Iceberg Lake seemed to have escaped the gradual assault.
"(Iceberg Lake) is pinned between these two glaciers just far enough away that it didn't get overrun by the Little Ice Age (glaciers)," Loso said.
So instead of having a record of just the last few hundred years, the floor of Iceberg Lake held a continuous record from 1998 back to A.D. 442, a span of more than 1,500 years.
That record is unique in that it seems to preserve a time of warmer temperatures called the Medieval Warm Period that happened before the Little Ice Age.
"It's the most recent time period warm enough to be comparable to the present," Loso said.
When Loso and his colleagues used the thickness of layers (called "varves") to interpret warmth in the area of Iceberg Lake, they found that summer temperatures in that part of the state were warmer in the late 20th century than they were during the Medieval Warm Period.
Not only that, they saw that Iceberg Lake had never drained during the Medieval Warm Period. Since the catastrophic leakage in 1999, the lake has drained of meltwater every year except for 2001. With such erratic behavior after centuries of stability, Iceberg Lake might be saying that Alaska has been warmer recently than it has been in a long, long time.
GGG Ping.
“Hey! Global Warming wackos! Give it up! That game is over, man!”
You beat me to it.
Last night on coast to coast there was a nutcase who claimed that all the mountains we see were created in about five minutes.
So “global warming” happened before, yet we’re here. Even southern real estate interests will survive, if they are willing to do a little real work on the side. ;-)
My first one (for me ONLY), LOL. (Dad got tired of me tangling his Shakespears)
Image of Alien spaceship found in the lake.
“Last night on coast to coast there was a nutcase who claimed that all the mountains we see were created in about five minutes”.
Bam! Mountanes!
LOL.
God can do that.
Why would God create things in fits and spurts to confuse and confound us when it would make more sense to set up a self consistent system of natural processes that tell his story of infinite wisdom with their beautiful simplicity?
In a related story, there were some satellite photos of the supposed remains of Noah’s Ark in the Turkish mountains. Sure looked like an alpine terminal moraine to me, but hey, that’s just me...
“Why would God create things in fits and spurts to confuse and confound us when it would make more sense to set up a self consistent system of natural processes that tell his story of infinite wisdom with their beautiful simplicity?”
Scotch?
Looks like a stinky to me.
It’s Bush’s Fault!
Note the sentence:
“That record is unique in that it seems to preserve a time of warmer temperatures called the Medieval Warm Period that happened before the Little Ice Age. “
The Little Ice Age corresponds to a period of unusually low sunspot activity called the Maunder Minimum [1], during which famines were caused by late frosts that killed food crops in New England and Europe. The point that caught my eye was that, according to this new climate record, it was overly warm just prior to that period. In the past few years, it has been warmer than normal, and just last week, it was announced that the normal cycle of sunspots has not started up, and another story in the Daily Tech[2] has a headline of “Temperature Monitors Report Widescale Global Cooling” and the lede of: “Twelve-month long drop in world temperatures wipes out a century of warming”.
My question: does this hint that we are headed for a similar perturbation in climate? If the sunspots don’t start up, the earth will be cooler, much cooler. If the sunspots follow the same pattern as they did in the Maunder Minimum, then we can expect the weather to also follow the same pattern: frosts, snow in July, crop failure and famine.
And this disaster cannot possibly be Bush’s fault! If the sun gives hints this is true, than it won’t be long before news sources that track sunspots will be more popular and easier to find on the net. For now, you can look at the web site of NASA’s SOHO [3]. The last solar image posted showed ZERO spots. [4]
see:
[1] http://en.wikipedia.org/wiki/Maunder_minimum
[2] http://www.dailytech.com/Temperature+Monitors+Report+Worldwide+Global+Cooling/article10866.htm
[3] http://sohowww.nascom.nasa.gov/data/data.html
[4] http://sohowww.nascom.nasa.gov/sunspots/
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