New Study Finds Arctic Experiencing Hottest Temps in Nearly 120,000 Years; Lead Author: All Baffin Ice Caps Set to ‘Eventually Disappear’

“All of Baffin Island is melting, and we expect all the ice caps to eventually disappear, even if there is no additional warming.” Gifford Miller, University of Colorado climate scientist and co-author of a recent scientific study entitled: Unprecedented recent summer warmth in Arctic Canada.

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(Satellite shot of Baffin Island and surrounding Arctic environs in September of 2013. Image source: NASA)

Baffin Island is a frozen archipelago situated to the west of Greenland and to the north and east of Hudson Bay. Like Greenland, it straddles the 70th parallel as well as the Arctic Circle. And like Greenland it is showing increasing signs of unprecedented warmth and melting. Though Baffin does not boast the massive ice caps of Greenland, large glaciers still cover much of its lands and fjords. The remaining areas are littered with small brown and green grasses and shrubs struggling up from rocky outcrops or from wide ranges of the now thawing tundra.

Like so many other places in our world, Baffin Island is a place where the deep past is coming into collision with a rapid and radical transition. A transition caused by humans and their endlessly increasing use of carbon-based fuels.

Over the past 150 years humans have released enough carbon dioxide into the atmosphere to achieve a global concentration of this gas that, by spring of 2013, exceeded 400 parts per million. This unprecedented high level, a level nearly 50% higher than the global concentration 150 years ago, was last seen on the Earth around 3.6 million years ago. And if past climate states are any true guide, then the vast volumes of greenhouse gasses already released into the atmosphere by humans are enough to melt all the ice on Baffin and at least half the ice on Greenland. It is this understanding of the effects of greenhouse gasses on past climates and ice states that prompted Miller to claim we’ve already released enough CO2 to melt the remaining ice on an isle that has been locked in freezing conditions since the dawn of humankind.

A Message From Earth’s Thawing Tundra

On Baffin and all over the high Arctic, vast swaths of the world’s tundra are rapidly being liberated from an eons-old ice cap. Scientists Gifford H. Miller, Scott J. Lehman, Kurt A. Refsnider, John R. Southon, and Yafang Zhong journeyed to Baffin’s thawing ice with a key question in mind: ‘When was the last time this region of the far north thawed?’ They came armed with the latest scientific tools and measures — tools that provided radio-carbon dating to determine the age of the most recently thawed plants. What the study found was chilling. Many of the plants newly liberated by the thawing ice were at least 44,000 years old. Others were possibly as old as 120,000 years.

This new evidence shows that the heat wave the Arctic is now experiencing, a heat wave that has driven sea ice deeper and deeper into the high Arctic, a heat wave that is melting, on average, about 500 gigatons of ice from Greenland each year (and about 25 gigatons of ice from Baffin), a heat wave that is turning millions of square miles of tundra into a melting, carbon-rich soup is hotter than even the hottest period during the last 11,000 years. And it shows that the Arctic probably hasn’t experienced this much melting since the last inter-glacial period — the Eemian.

The more recent time marking a space from the end of the last ice age to the present day is known as the Holocene. It marks the most recent geological epoc. During the early and middle years of the Holocene, solar insolation — or the measured amount of radiation coming from the sun — was as much as 9% stronger. But, according to the recent paper, human greenhouse gas emissions have been enough to completely overwhelm even the peak Holocene heat effect of a 9% stronger Arctic sun experienced centuries and centuries ago:

“The key piece here is just how unprecedented the warming of Arctic Canada is,” Gifford Miller, a researcher at the University of Colorado, Boulder, said in a joint statement from the school and the publisher of the journal Geophysical Research Letters. “This study really says the warming we are seeing is outside any kind of known natural variability, and it has to be due to increased greenhouse gasses in the atmosphere.”

It’s amazing to think that humans have already set in effect levels of warmth unsurpassed in 44,000 years and, possibly, 120,000 years. This new information, in itself, is unprecedented. But don’t make the mistake of falling into the false and relative comfort of thinking we only need to worry about the climates of 120,000 years ago. We’re already passing that marker now. As mentioned above, we’ve already released enough greenhouse gasses to at least return Earth to climates not seen in 3.6 million years. In this respect, the Baffin Island study adds to research conducted at Lake El’gygytgyn showing that levels of CO2 comparable to those seen today resulted in Arctic temperatures 8 degrees Celsius hotter during the deep past.

Rapidly Changing Arctic to Liberate More Greenhouse Gasses

Sadly, it is Miller’s final statement, the one stating that all the ice on Baffin is bound to melt, no matter what, which bears the most weight in our current day. With coal plants still being constructed at a break-neck pace in India and China, and with human greenhouse gas emissions rising above 45 gigatons of CO2 equivalent each year, we would be lucky if the end level of melt only included the ice on Baffin combined with a large section of the ice over Greenland. Instead, we are rapidly forging along toward a CO2 level of 550 to 600 ppm which will almost certainly ensure a dangerous and rapid melting of all the remaining ice on Earth.

In addition, billions of tons of carbon in the form of methane and CO2 lay locked within the millions of square miles of thawing permafrost. Some of this methane and CO2 is already out-gassing, adding to the already dangerously high levels of human greenhouse gasses.

Over the past month, the Arctic saw major methane spikes in which atmospheric concentrations of this potent greenhouse gas reached nearly 2500 parts per billion, more than 650 parts per billion above the global average. And should the Arctic continue to warm we are more likely to see even larger spikes of both methane and CO2 further amplifying already unprecedented Arctic warmth.

Most likely, we are headed to at least the temperatures last seen during the Pliocene, in which global averages ranged 2-3 degrees Celsius hotter than the present and during which oceans were 25-75 feet higher. Unfortunately, these are the long-term consequences we have probably already locked in. But without rapid reductions in carbon emissions to near zero over the coming decades, we can expect far, far worse outcomes.

Links:

Unprecedented Recent Summer Warmth in Arctic Canada

Arctic Temperatures at 44,000 year High

NASA/Lance-Modis

The Eemian Interglacial

Latest Methane Data Provided by USGS and Methane Tracker

Accelerated Contributions of Canada’s Baffin and Byot Island Glaciers to Sea Level Rise Over The Past Half Century

Posted by robertscribbler on November 5, 2013

https://robertscribbler.wordpress.com/2013/11/05/new-study-finds-arctic-experiencing-hottest-temps-in-nearly-120000-years-lead-author-all-baffin-ice-caps-set-to-eventually-disappear/