Two new studies say different things about Greenland’s icecap history

The uncertainty of science: Two new studies of Greenland’s icecap suggest completely opposite histories, with one saying that Greenland was ice free at least once in the past 2.6 million years, with the other saying that the icecap covered Greenland continuously for the past 7.5 million years.

Evidence buried in Greenland’s bedrock shows the island’s massive ice sheet melted nearly completely at least once in the last 2.6 million years. This suggests that Greenland’s ice may be less stable than previously believed. “Our study puts Greenland back on the endangered ice-sheet map,” says Joerg Schaefer, a palaeoclimatologist at the Lamont-Doherty Earth Observatory in Palisades, New York, and co-author of a paper published on 7 December in Nature.

A second paper in the same issue paints a slightly different view of the ice sheet’s past stability. A group led by Paul Bierman, a geomorphologist at the University of Vermont in Burlington, found that ice covered eastern Greenland for all of the past 7.5 million years. Experts say the two papers do not necessarily contradict one another: at times, nearly all of Greenland’s ice could have melted (as seen by Schaefer’s team) while a frosty cap remained in the eastern highlands (as seen by Bierman’s group).

If all of Greenland’s ice melted, it would raise sea levels by seven metres. Models suggest that Greenland could become ice-free as soon as 2,500 years from now, depending on the concentration of greenhouse gases in the atmosphere. [emphasis mine]

This story is a perfect example of how the passionate belief in a theory (that global warming is happening, is a threat, and will melt the icecaps) can warp a scientist’s thinking. Both studies used a single drilled ice core, with the first from Greenland’s central region and the second from Greenland’s eastern region. Thus, there is no reason to say that the entire Greenland icecap had melted, as noted in the highlighted text that describes the first study. What the data merely suggests is that these two regions might have had different histories.

Instead, the article, in its effort to confirm the possibility that Greenland’s icecap could melt entirely and thus pose a threat of a big sea level rise, ignores this simple detail and struggles to justify the concept that the entire cap certainly melted in the past, even though one study suggests otherwise. This causes everyone to misunderstand the results, and draw conclusions that are uncalled for, based on the available data.

How global warming activists ended up getting stuck in the ice fields surrounding Antarctica.

How global warming activists ended up getting stuck in the ice fields surrounding Antarctica.

The first error expedition leaders made was under-estimating the prevailing sea ice conditions at Mawson Station, their destination. The scientists seemed to be convinced that Antarctica was a warmer place today than it had been 100 years earlier, and thus perhaps they could expect less sea ice there. This in turn would allow them to charter a lighter, cheaper vessel.

And then there’s this:

Why the vessel got trapped in the first place may be because [project leader and professor Chris] Turney never bothered to look at sea ice charts, which showed near record high levels of sea ice surrounding Antarctica. Moreover, Turney even denied that the overall sea ice trend was expanding around the continent. Fox News writes, “Turney said it was ‘silly’ to suggest he and 73 others aboard the MV Akademic Shokalskiy were trapped in ice they’d sought to prove had melted. He remained adamant that sea ice is melting, even as the boat remained trapped in frozen seas.

Did he expect to find less ice than Mawson did 100 years earlier? This appears to be what he expected, given his expedition’s planning. [emphasis mine]

In other words, this group and its so-called scientific leader are typical of the entire global warming climate community. Facts are irrelevant. The Earth is warming, the icecaps are disappearing, and to hell with any data that says otherwise.

Eventually, however, reality bites. Personally, I would much rather focus on reality first, so that I am prepared to deal with it when it jumps up at me.

The Antarctica icecap is now grown to be the largest it has been in 35 years.

The uncertainty of science: The Antarctica icecap is now grown to be the largest it has been in 35 years.

Antarctic sea ice has grown to a record large extent for a second straight year, baffling scientists seeking to understand why this ice is expanding rather than shrinking in a warming world. On Saturday, the ice extent reached 19.51 million square kilometers, according to data posted on the National Snow and Ice Data Center Web site. That number bested record high levels set earlier this month and in 2012 (of 19.48 million square kilometers). Records date back to October 1978.

Uh, maybe the world isn’t warming as predicted?

Despite the significant increase in the Arctic icecap’s size this winter, satellite data of the icecap’s actual volume and thickness suggest that the new ice was quite thin.

The uncertainty of science: Despite the significant increase in the size of the Arctic Ocean’s icecap this winter, satellite data of the icecap’s actual volume and thickness suggest that the new ice was quite thin.

Prof Andy Shepherd, from Leeds University, said: “Now that we have three years of data, we can see that some parts of the ice pack have thinned more rapidly than others. At the end of winter, the ice was thinner than usual. Although this summer’s extent will not get near its all-time satellite-era minimum set last year, the very thin winter floes going into the melt season could mean that the summer volume still gets very close to its record low,” he told BBC News.

It is not surprising that the ice was thin, considering that the icecap was recovering from a record low the year before. The scientific question, however, is whether the cap will thicken in the coming years or continue to thin out. That it has recovered somewhat in size might be a onetime jump as the decline continues, or it might be indicative of a new growing trend.

Despite the decline in Arctic sea ice during the past decade the population of polar bears in the Davis Strait has skyrocketed.

Despite the decline in Arctic sea ice during the past decade the population of polar bears in the Davis Strait has skyrocketed.

The increase might have even placed the population at the carrying capacity for the region.

In related news, the New York Times has finally admitted to the fact that the climate stopped warming fifteen years ago.

At the same time, the reporter has a great deal of trouble dealing with this fact, mainly because he refuses to recognize that the theories of carbon-dioxide-caused global warming might be mistaken.

New data from Antarctica suggests that the south pole icecap is not warming, as predicted by climate models.

New data from Antarctica suggests that the south pole icecap is not melting, as predicted by climate models.

It turns out that past studies, which were based on computer models without any direct data for comparison or guidance, overestimate the water temperatures and extent of melting beneath the Fimbul Ice Shelf. This has led to the misconception, Hattermann said, that the ice shelf is losing mass at a faster rate than it is gaining mass, leading to an overall loss of mass. The model results were in contrast to the available data from satellite observations, which are supported by the new measurements.

The team’s results show that water temperatures are far lower than computer models predicted, which means that the Fimbul Ice Shelf is melting at a slower rate. Perhaps indicating that the shelf is neither losing nor gaining mass at the moment because ice buildup from snowfall has kept up with the rate of mass loss, Hattermann said.

In other words, the climate models were wrong. When actual data was obtained, first by satellites and now from the water under the ice shelf itself, the new data found that the ice shelf is stable, not melting as predicted.

Times Atlas shows ice free areas of Greenland that are not ice free

When faith trumps data: The most recent edition of the Times Atlas incorrectly shows large areas of Greenland free of ice, claiming this was caused by global warming, even though those areas remain ice-covered. More here.

The Scott Polar group, which includes director Julian Dowdeswell, says the claim of a 15% loss in just 12 years is wrong. “Recent satellite images of Greenland make it clear that there are in fact still numerous glaciers and permanent ice cover where the new Times Atlas shows ice-free conditions and the emergence of new lands,” they say in a letter that has been sent to the Times. “We do not know why this error has occurred, but it is regrettable that the claimed drastic reduction in the extent of ice in Greenland has created headline news around the world. There is to our knowledge no support for this claim in the published scientific literature.

Wither the Arctic Icecap?

In a paper published today in Geophysical Research Letters, climate scientists have estimated the distribution and trends for the Arctic icecap from 1980 through March 2011. What they have found is a significant decline in older ice on top of an overall declining trend that showed a strong but partial recovery since 2008. The graph below, from the paper, illustrates clearly these trends.

Arctic Ice, 1980 - 2011

What this means for the icecap itself remains unclear. As the scientists themselves note in their conclusion:
» Read more

Water and ice at the bottom of the Antarctic Ice Sheet

The uncertainty of science: Unexpectedly large amounts of flowing water and refrozen ice found at the bottom of the Antarctic icecap. Key quote:

It’s too early to know whether this new finding means that global warming will melt ice sheets slower or faster than scientists have predicted. But the work does suggest that current models of ice sheet dynamics are missing a huge factor, said glaciologist Donald Blankenship of the University of Texas, Austin. “The take-home message of this work is that [the bottom of ice sheets] can no longer be ignored” in the models, he says.

Arctic icecap reaches 2010 minimum

It appears that the Arctic icecap has reached its 2010 minimum. Though the icecap extent in the spring was the largest since 2002 (see image below), the melt was fast and the minimum appears to be the third lowest since 1979.

Icecap extent

Does this mean the icecap is melting and will disappear shortly, as some politicians like to believe? Hardly. Though the data suggests a long term decline in ice extent, recent trends also show evidence that the icecap might be recovering. What will actually happen is still anyone’s guess.

Greenland icecap is not melting

Steve Goddard has posted on Anthony Watt’s webpage a very detailed update on the state of the icecap covering Greenland. Surprise! There are no signs of it disappearing anytime soon. (Note that you might have to scroll to the right to see the text of Goddard’s post, as on some computers Watts’s webpage is unfortunately far too wide for the screen.)