Print 59 comment(s) - last by tygrus.. on Jan 13 at 8:07 PM

A temperature color mapping of the effects of a closed Bering Strait. The northern Pacific cools while the northern Atlantic warms significantly enough to bully Norther American climate.  (Source: Nature/UCAS)

The unassuming 53 mile Bering Strait hardly seems like the type of geological formation that would cause this kind of trouble.  (Source: Wikipedia commons)
It comes down to one little strait and some really big sheets of ice.

The Bering Strait, spanning a distance of approximately 53 miles between Alaska and Russia, looks like an unassuming place for temperature regulation for the entire North American region (including Greenland), but recently published NCAR/UCAR findings seem to indicate that it may be very geologically important.

The strait serves as a gate for cooler, less salinized water from the Pacific to flow to the warmer and saltier Atlantic. Their simulations found that without this flow, the climate of North America fluctuates much more rapidly – in the span of a few thousand years rather than some tens of thousands – and helps explain constant temperature and ice sheet modulation between 116,000 and 34,000 years ago, a time of constant ice sheet advance and retreat.

In the past, this pattern was often attributed to the Earth’s position along its 95,000 year orbital pattern, but the NCAR researchers found that when correlated with the temperature and ice data, the orbit could not explain the rapid fluctuations. Instead, it occurred to them that changes to the Bering Strait itself could have a large impact on the entire region due to the changes it would bring to the Pacific and Atlantic ocean currents. Their models indicate that a slight change in the strait would adversely affect the meridional overturning circulation, an ocean current which helps drive the Atlantic tropics-to-polar heat pump.

In the simulation, they show that around 110 to 115 thousand years ago, the northern climate cooled sufficiently to create giant ice sheets over the northern regions of North America and all of Greenland. As these ice sheets sucked up water from the global oceans, sea levels dropped by as much as 100 feet. Eventually a vast amount of the strait was no longer able to pass water – the average depth of the strait is 100 - 190 feet. The new land bridge cut off a vast portion of the ocean flow between the Pacific and Atlantic. This, in turn, caused the Pacific ocean to become even cooler and cleaner, but allowed the now saltier waters of the Atlantic to push the meridional overturning circulation into overdrive, warming the regional ocean, North America and Greenland by as much as 1.5C over a few thousand years.

Next, the regional warming caused the iced sheets to melt over another few thousand years, returning the oceans to their previous depth and reopening the Bering Strait. With the Atlantic’s access to cooler and cleaner water from the Pacific restored, the cycle started all over again.

These temperature oscillations went on like a driver overcompensating for an icy road fishtail until finally, around 34,000 years ago, the Earth’s distance from the sun was so great that it literally froze the fluctuation in place. About 10,000 years ago, the Earth had finally gotten close enough to the sun again to warm up the northern hemisphere to the point where the strait reopened slowly and the temperature variations settled into a much more docile animal.

This study helps to provide convincing data for two things: that a significant change in something even so geographically small can adversely affect the climate of an entire quadrant of hemisphere, if not an even greater area, and that the planet has its own regulatory devices to deal with such things. However, it remains to be seen how long the cycle would have gone on if not for the fortuitous position in the orbital cycle. Too, this study reflects nothing at all of man’s influence on these climate systems in current times. The key to understanding these things lies in first understanding the basic driving forces behind climate systems and the NCAR study has shown us how one such small system may operate.

Comments     Threshold

This article is over a month old, voting and posting comments is disabled

By Regs on 1/12/2010 10:21:46 AM , Rating: 2
This article is about the Earth self regulating itself. Almost like if humans dropped 100 or so a-bombs it would regulate our asses right off the face of it. So the skeptics would still hold water.

The Earth has a different perception of time. A few million years to her, is like a couple of decades to us. It also does not see time like we do. It also does not rationalize, consume, retaliate, or judge. It's a perfect animal. I am much more confident in her than I will ever be with any human.

By Solandri on 1/12/2010 12:56:20 PM , Rating: 2
The 1980 eruption of Mt. St. Helens (relatively small as volcanoes go) was about 24 megatons, or equivalent to ~1600 Hiroshima-sized atomic bombs. The largest recorded volcanic event, Krakatoa in 1883, was about 200 megatons, or 13,000 Hiroshimas. The energy released by the 2004 Indian Ocean earthquake (which subsequently caused the tsunami which killed a quarter million people) was equivalent to 9,560,000 megatons, or 550 million Hiroshimas. Fortunately, very little of that energy (about 26 megaton's worth) reached the earth's surface.

Nuclear weapons are small potatoes compared to nature.

By tygrus on 1/12/2010 6:43:37 PM , Rating: 2
The 1980 eruption of Mt. St. Helens:
* radio carbon dating 1'000's years= failed;
* uranium dating 100'000's years= failed;
* rock stratification over 1'000's years = failed;
* plant matter to coal over million years = failed;
* dating age of rock based on fossils = failed;
* valleys caused by erosion over 1'000's years = failed;
* slow re-vegetation = failed;
* modern scientific theories = failed.
The traditional dating methods came back with varying results that were way off the actual time and age of events. They observed what was thought to take millions of years in a matter of months.

By Camikazi on 1/12/2010 10:35:50 AM , Rating: 2
Amen, it's hard for me to trust humans with anything on a national level, they start talking about global level or stopping the Earth form doing what it normally does and I get scared. If we start trying to change the Earth's normal climate changes to keep the temperate where we want it bad things will happen. I am sure the planet has it's own fail-safes we can't figure out, we make too many large scale changes and the planet will do what it has to, to correct itself.

By ClownPuncher on 1/12/2010 1:02:05 PM , Rating: 2
So you watched that crappy, retarded M. Knight Shmidgetfucker move, The Happening?

By Connoisseur on 1/12/2010 3:03:08 PM , Rating: 1
Wow you have some anger for that guy it seems... I don't particularly like has last few movies but damn that's anger.

By ClownPuncher on 1/12/2010 3:40:07 PM , Rating: 2
I put on my robe and wizard hat.

By porkpie on 1/12/2010 4:37:21 PM , Rating: 2
"Global warming is the planet self-correcting. It's responding to pollution by eliminating the cause, humans. "

The most frightening thing about statements like this is how much misanthropic self-hatred they reveal. I just wish people that believed this crap would stop having kids entirely, and breed themselves out of existence. If they really believed what they preach, they'd do it anyway, right?

By porkpie on 1/12/2010 3:41:18 PM , Rating: 2
" Almost like if humans dropped 100 or so a-bombs it would regulate our asses right off the face of it"

Lol, what? Even the widely-discredited "nuclear winter" theory postulated several thousand nuclear explosions in order to cause any serious climate change. And of course, the science behind that was pretty laughable.

100 nuclear bombs might take out 10% of the US population or so. Worldwide effect? zero.

"It looks like the iPhone 4 might be their Vista, and I'm okay with that." -- Microsoft COO Kevin Turner

Copyright 2016 DailyTech LLC. - RSS Feed | Advertise | About Us | Ethics | FAQ | Terms, Conditions & Privacy Information | Kristopher Kubicki