Greenland's Thawing ice alarms scientists: "losing the equivalent of Lake Houston every 6 hours"

Houston Chronicle ^ | Aug. 14, 2006 | ERIC BERGER

[rface]

Greenland's massive ice sheet is melting rapidly, losing the equivalent of Lake Houston every six hours.

That's the conclusion of a study by University of Texas at Austin scientists that appears to confirm earlier, controversial research that suggests the melting of Greenland's ice has nearly tripled since the late 1990s. Greenland's ice sheet contains about 10 percent of the world's fresh water.

The findings concern climate scientists, who say that since the Industrial Revolution, and especially since the mid-1900s, carbon dioxide levels have risen by more than 40 percent. They attribute much of the increase to fossil fuel burning and say that, in the absence of increased carbon emissions, no natural factor can explain warming global temperatures.

The warming effect, scientists fear, is accelerating and could lead to rising sea levels.

"This is a good indication of global warming, that it's there," said the study's lead author, Jianli Chen, a researcher at UT's Center for Space Research. "At least, it's happening in the Arctic."

Using two satellites that measured the change in the mass of Greenland's ice sheet, the researchers, publishing last week in the journal Science, found that Greenland was losing 57 cubic miles of ice a year.

At that rate, Greenland is raising sea levels by less than a half-inch per decade. But still more rapid ice loss could accelerate that rate. If all of Greenland's ice were to melt, seas would rise by 21 feet.

"Existing ice sheet models estimate that most of the ice sheet will be removed within 1,000 years," said Eric Rignot of NASA's Jet Propulsion Laboratory in Pasadena, Calif., lead author of the Greenland ice study earlier this year that the new work seems to confirm.

"This is a very conservative estimate, and the time scale is at least three times too large. Whether it will happen in the next century, we do not know. But, realistically, every year we look at Greenland, we realize that things are changing faster than we thought."

One of the first scientists to study Greenland's thinning ice sheet, NASA glaciologist William Krabill, said the two new studies make a strong case that the melting of Greenland has accelerated.

"There is no question that the sign is correct, Greenland is thinning and losing mass," Krabill said.

He added, however, that there are limitations on the new research. The satellites only began collecting data in 2002, making it difficult to discern whether the recent ice loss is part of a long-term trend.

Chen said he's expecting the two satellites used in the study to continue collecting data through at least 2010.

Scientists say coastal residents shouldn't be immediately concerned about rising seas due to glacial melting in Greenland and Antarctica, where there is increasing evidence that a warming climate also is causing ice loss.

"Houston has produced much larger apparent sea level changes locally through groundwater pumping, and coastal construction contributes to receding coastlines," said Texas State Climatologist John Nielsen-Gammon, an atmospheric sciences professor at Texas A&M University.

"We saw in New Orleans the effect of marsh drainage and upstream damming of sediment on the height of land relative to sea level. I expect that, for the next several decades, what Texans do directly to our coast will have a much bigger effect than what global warming will do to our coast."

[10mm]

...carbon dioxide levels have risen by more than 40 percent.

YAWN! Carbon dioxide is plant food. Wake me up if oxygen levels start decreasing.

[lepton]

The satellites only began collecting data in 2002,

IIRC, the growth in ice mass reversed in 2003 - along with 1998, an exceptionally hot year.

[texas_mrs]

I have heard of water wells going totally dry on some ranches in a neighboring county. Pretty scary stuff. We have had under 2" rain for several months running now.

[fhayek]

To quote Jerry Seinfeld: "but I don't wanna be a pirate!"

[Zon]

 

Want to see an enviro-whacko's head explode? Show 'em this.

The following graphs show that Earth is in a brief period of global warming called an interglacial. The longer time spans, the deep troughs are glacial periods. The line that runs across the graphs is the temperature in 1950 and listed as "0" on the left axis.

As can be seen in the last graph (Figure 1-5), Earth appears ready to move toward another ice age in the cycle.

I'm more concerned with sustaining global warming to offset global cooling and the next ice age.

Ice Ages & Astronomical Causes
Brief Introduction to the History of Climate
by Richard A. Muller

Origin of the 100 kyr Glacial Cycle

This first graph looks bad, doesn't it -- steeper upward temperature trend. Horizontal red line is temperature at 1950.

Figure 1-1 Global warming

The second graph shows today's temperature isn't out of the norm. Horizontal blue line is temperature at 1950.

Figure 1-2 Climate of the last 2400 years

The next graph shows a downtrend in temperatures from 8,000 years ago to today. The down trend is steeper in the recent 2,000 years. From left to right the upper spikes have lower highs while the lower spikes have lower lows. (The same effect can be seen in Figure 1-2, above.) 

Figure 1-3 Climate of the last 12,000 years

This graph shows that agriculture and  stationary societies emerged 8,000 years ago during a time frame when global temperature was much higher than normal, or average.

Figure 1-4 Climate of the last 100,000 years

The next graph shows that the recent 8,000 years was one of five brief hot spikes when glaciers were at minimums. With much longer troughs when glacials (ice ages) were the norm most of the time.

Figure 1-5 Climate for the last 420 kyr, from Vostok ice

The graph below is reversed. That is, the left side is present day and the right side is 3 million years ago. It shows a 3 million year down trend toward widening extremes in the temperature cycle.

Figure 1-6 Climate for the last 3 million years

 

[bjc]

Let me see if I understand this correctly. They have 4 years of data and they are projecting results 1000 years down the road!! That is some powerful model that must be based on a ton of well proven relationships resulting in microscopic error terms. Alternatively perhaps these scientists are a facing a renewal of their NSF grant.

[Deguello]

"We may not be happy if the Greenland sheet melts, but..."

There are lots of WWII aircraft to be recovered if it would quit snowing.

[lepton]

So Greenland will return to the state it was in when the vikings first ran into it back about 1000 years ago. It didn't get its name for its gigantic glaciers.

It wasn't all that green. That was exaggerated. That is not, however, to say that the green areas were not considerably more expanded than they are now.

[LasVegasMac]

So Greenland will return to the state it was in when the vikings first ran into it back about 1000 years ago. It didn't get its name for its gigantic glaciers.

Oh, come on. There ya go again, peeing on their parade with those nasty little facts.

You really are hard core.

[<1/1,000,000th%]

That means it's time to short temperature futures.

[MrEdd]

AAaarrr

[Zon]

Yep. Glad someone saw that too. Are you a technical analyst?

[dangus]

Material in this posts describes how, overall, 90% of the Earth's glaciers are growing; Antarctica, except for the one small peninsula they report in the news constantly, is seeing its ice mass grow by trillions of tons.

http://www.freerepublic.com/focus/f-news/1644060/posts

[Nickname]

My only experience with Lake Houston involved zillions (possibly quad-zillions) of May flies and extreme heat.

And mosquitos.

I came out of it looking like I had chicken pox.

Can't say I'd miss a Lake Houston disappearing every six hours.

[bjc]

Love it!! I assume Krabill and Miller talk a lot!

[w1andsodidwe]

At that rate, Greenland is raising sea levels by less than a half-inch per decade. But still more rapid ice loss could accelerate that rate. If all of Greenland's ice were to melt, seas would rise by 21 feet.

A frozen a full bottle of water in the freezer the other day. Guess what? The ice took up more space than the original water, distorting the plastic bottle. I then melted the ice back to water and the level in the bottle fell back to original levels.

Yeah, I know ice bergs stick out of the water, but there is a whole lot more underneath, otherwise they would be top heavy and fall over.b

[<1/1,000,000th%]

Not a good one. ;)

[bjc]

Love it!! I assume Krabill and Miller talk a lot!

Sorry,
Muller not Miller

[rdax]

At New Orleans, the average flow rate of the Mississippi is 600,000 cubic feet per second......

If this is true, I think we need to worry more about all the ice we're losing along the Mississippi every year. Who cares about Greenland!?

We must stop the flow of the Mississippi, now!!

[Scotsman will be Free]

But, but, but where's my hockey stick?