Flow of research on ice sheets helps answer climate questions

Feb 16, 2013

Just as ice sheets slide slowly and steadily into the ocean, researchers are returning from each trip to the Arctic and Antarctic with more data about climate change, including information that will help improve current models on how climate change will affect life on the earth, according to a Penn State geologist.

"It is not just correlation, it is causation," said Richard Alley, Evan Pugh Professor of . "We know that warming is happening and it's causing the sea levels to rise and if we expect more warming, we can expect the sea levels to rise even more."

Alley, who reports on his research at the annual meeting of the American Association for the Advancement of Science in Boston, has studied the movement of ice sheets in Greenland and the Antarctic over the years. One way researchers are measuring is by collecting data on how fast ice sheets are flowing toward the sea and comparing those speeds over time, according to Alley.

Ice sheets are miles-thick, continent-wide layers of ice that spread toward the oceans. The researcher said that rising speeds melting in warmer parts of ice sheets, contributing to sea-level rise. Ocean warming can melt the floating ice shelves that form in bays and fjords around ice sheets. This lowers the friction with the rocky coast, allowing non- to flow more rapidly into the and raise the sea level, Alley said.

However, when the climate is warmer, build up beneath the ice and allow it to float higher above the rocks, cutting down on the friction. Researchers have reported that the speed of the ice shelf movement has nearly doubled in recent years.

Rapid ice-shelf melting also leads to sea level rises, Alley said. The more quickly the ice can enter the sea, causing sea levels to rise. The areas of uncertainty are how much the sea levels will rise and how soon it will happen, the researcher said.

Currently, scientists have projected a range of probabilities about how high and how quickly the seas will rise, Alley said. Now, they are trying to better understand whether sea level rise will happen gradually, like a dial, or abruptly, like a switch, he said. "If you turn a dial, such as a dimmer on an overhead light, you can change the brightness gradually, but with a switch, it is either on or off," said Alley.

Most planners expect the to rise gradually. If sea levels do change minimally and slowly, there will still be costs, but people and governments will have more time to deal with the problems—for instance, by building walls and replenishing beaches with sand.

However, if sea levels rise fast and suddenly, the cost to fix the damage and prepare for further problems will increase rapidly, according to Alley.

"If the sea rises faster, then it can be much more expensive," said Alley. "The prices will go up much faster than the sea levels." Alley expects future research projects will help scientists better predict the rate and size of .

"The great thing is that this is a wonderful period of discovery and exploration in places like Greenland and the Antarctic," said Alley. "In the next few year we'll see even more progress."

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ahaveland
4.4 / 5 (7) Feb 16, 2013
Better get on with finding a solution quickly, time is running out.

http://thinkprogr...llapsed/
The Alchemist
1 / 5 (8) Feb 16, 2013
Huh, somewhat rhetorical... glacial melt caused local cooling in the Pacific North West. If we hit a tipping point, and enough ice melts to affect the globe, will we see the Global Temperature decrease, yet... the causation of Global "Warming" continue?
deepsand
3.4 / 5 (8) Feb 17, 2013
Huh, somewhat rhetorical... glacial melt caused local cooling in the Pacific North West. If we hit a tipping point, and enough ice melts to affect the globe, will we see the Global Temperature decrease, yet... the causation of Global "Warming" continue?

The question betrays a total lack of understanding of the basic underlying principles of Physics.

Not only does melting not entail a decrease in the total thermal energy of the system in question, but in this case creates a positive feedback loop that increases it.

A decrease in white ice and snow decreases Earth's albedo, which results in short wavelengths of Solar irradiation being absorbed rather than being reflected, which raises surface temperatures, which in turn results in more thermal energy being re-radiated at infrared wavelengths, which increases radiative forcing, thus raising the total thermal energy of the system.
NikFromNYC
1.4 / 5 (11) Feb 17, 2013
The standard sea level study is that of Church & White. The latest update included a plot of the simple average of world tide gauges that debunks all claims that recent sea level rise represents a change in trend in our high CO2 era, since it's an arrow-straight line with just a bit of noise:

http://oi51.tinyp...koix.jpg

Details: http://climatesan...el-data/

The headlines scream louder but the trend remains the same.
Steven_Anderson
2.8 / 5 (9) Feb 17, 2013
We should start instituting carbon capture. It's an economical solution world wide. I have churned out the numbers. Here they are: http://rawcell.co...capture/ It's worth reading! Please read and check my numbers!
NikFromNYC
1.3 / 5 (10) Feb 17, 2013
We should start instituting carbon capture. It's an economical solution world wide.


A great way to kill the poor, indeed, by first making energy more expensive and then removing plant food from worldwide agricultural production. Eugenicists can cheer this program on as it culls the weak from the gene pool. Alas, anti-fracking activists won't want this in their backyards, nor do I since CO2 is a toxic gas to humans and causes water to turn to corrosive acid.
NikFromNYC
1.4 / 5 (11) Feb 17, 2013
We should start instituting carbon capture. It's an economical solution world wide.


Now if you came up with a *use* for the CO2 then your plan wouldn't be so evil. It's a highly reactive reagent that could likely feed into the vast network of oil industry chemicals used to make plastics and medicines. CO2 reacts with nitrogen functional groups to form relatively inert carbonates. If you pour a simple unbranched amine into a Petri dish it quickly clouds up as it sucks CO2 up from the air. Now, given that CO2 is plant food, why would you pay to *bury* it rather than use it for vast algae farms?
The Alchemist
1.4 / 5 (11) Feb 17, 2013
Carbon capture-at the risk of sounding like the guy who said everything had already been invented, preposterous.
The Earth used to have the capacity to suck up more CO2 than we can produce, yet no one seems to be interested in what we've done to diminish this capability. "Dead Zones" (wiki) seem to be the best we can come up with.
@Deepsand-you're absolutely right! If I break an ice cube up it certainly does not cool my drink (faster). In fact it warms it up, I am surprised I never noticed this effect before. And the feedback effect, gosh, I guess I never realized water is the most dense at 4 C and... thanks for playing.
deepsand
3.5 / 5 (8) Feb 17, 2013
@Deepsand-you're absolutely right! If I break an ice cube up it certainly does not cool my drink (faster). In fact it warms it up, I am surprised I never noticed this effect before. And the feedback effect, gosh, I guess I never realized water is the most dense at 4 C and... thanks for playing.

The total thermal energy of the ice/drink system remains the same.

You fail.
VendicarE
3.7 / 5 (12) Feb 17, 2013
If CO2 is "highly reactive" then how is it that it is the final stable product of combustion?

If it were "highly reactive" then it would react with something else wouldn't it?

"CO2 then your plan wouldn't be so evil. It's a highly reactive reagent" - NikfromNY

Learn some science Nikkie. Continuing to live a life of ignorance will just make you more cranky and bitter as you become a stupid old man.
VendicarE
3.7 / 5 (12) Feb 17, 2013
Of course, there are no "intert carbonates" in plant tissue since the carbonates are in solution and at equilibrium with the dissolved CO2 in the cytosol.

Further, CO3 forms in the presence of nitrogen functional groups is because the nitrogen group is more reactive than CO2 and gives up an Oxygen to a CO2 molecule that otherwise doesn't want it.

If CO2 were not so reluctant to accept oxygen then combustion would produce CO3 rather than CO2.

"CO2 reacts with nitrogen functional groups to form relatively inert carbonates" - NikfromNY

Poor Nikkie. He lives a science free life of intellectual poverty.
The Alchemist
1 / 5 (6) Feb 18, 2013
Reactivity depends on the environment. What is highly reactive in one situation is intert in another. We tend to think of something as being stable relative to reacting with good old water. CO2 is basically inert, but is not inert to plants, for example. Niks' a little wild, but he has his moments.
@Deepsand, huh? You mean my drink does not get colder because the ice melts. I wasted all those thermo classes. The energy comes from melting the ice, and the energy from phase transitions (solid to liquid) is huge, even though it is not intuitive. It most certainly does not remain the same, even discounting energy from mixing. Thanks for playing, even after the whistle blows.
The Alchemist
1 / 5 (5) Feb 19, 2013
@Deepsand-let me apologize for my attitude-I was a little rankled by your lack of physics comment. Here's the situation as I see it, and I invite your criticisms:
Warm weather/air comes to the poles from, well, everywhere else. That warmth raises the ice temperature to 0 C, where it takes 1 calorie per- to raise it to 0, and 1400x that to melt it. Where the temperature REMAINS THE SAME! This icy-cold water runs into rivers lakes and oceans, cooling them (except for near antarctic, and very near arctic seas, which warm, slightly).
The effect of water, both melting and flowing into various reservoirs is a tremendous buffering/cooling effect.
One criticism that comes to mind is the melting in the polar seas-but I am pretty sure most of the melting will not occur until it reaches the melting point of fresh, not salt water.
Peace?
deepsand
4 / 5 (4) Feb 19, 2013
None of which refutes what I earlier said, and here repeat, which is, despite your claim to the contrary, indeed based on elementary Laws of Physics.

Not only does melting not entail a decrease in the total thermal energy of the system in question, but in this case creates a positive feedback loop that increases it. A decrease in white ice and snow decreases Earth's albedo, which results in short wavelengths of Solar irradiation being absorbed rather than being reflected, which raises surface temperatures, which in turn results in more thermal energy being re-radiated at infrared wavelengths, which increases radiative forcing, thus raising the total thermal energy of the system.
The Alchemist
1 / 5 (6) Feb 19, 2013
Err, we are clearly not talking apples to apples... melting requires energy. The Earth radiates heat from the poles, absorbes little... and I don't know the origin of your feedback.
deepsand
3.7 / 5 (3) Feb 19, 2013
melting requires energy.

Only a transfer of energy, not necessarily the introduction of additional energy.

And, does not refute what I said re. a positive feedback loop, which was described in detail that you are assiduously avoiding.
The Alchemist
1 / 5 (4) Feb 21, 2013
I am not avoiding, I am missing completely. Please explain more specifically, what is the feedback origin? If you mean albedo at the poles-it is negligible...
http://www.elic.u...de6.html
"Transfer..." I will have to stand on a principle that applies to waste and waste heat: "There is no 'away' to 'through to'..." We'll have to agree to disagree. But respectfully, I hope.
deepsand
3.7 / 5 (3) Feb 21, 2013
I am not avoiding, I am missing completely. Please explain more specifically, what is the feedback origin?[/quote]
Already laid out in detail.

If you mean albedo at the poles-it is negligible...
http://www.elic.u...de6.html

Your own citation says otherwise.

"Transfer..." I will have to stand on a principle that applies to waste and waste heat: "There is no 'away' to 'through to'..."

Sophistry.
deepsand
3.7 / 5 (3) Feb 21, 2013
We'll have to agree to disagree.

On matters of opinion, perhaps; but, on those of facts, never.

While you are indeed entitled to your own opinions, you are not entitled to your own "facts."
The Alchemist
1 / 5 (4) Feb 22, 2013
My facts are these, the Earth is not a closed system. It receives heat from the Sun and from burning of fossil fuels. The melting I am referring to is the "un-naturally" rapid melting of our poles, clearly caused by a change to the environment, clearly not from the annual "transfer" I think you mean(?).
Good catch on the poles albeto, I stand corrected.
deepsand
3.7 / 5 (3) Feb 22, 2013
My facts are these, the Earth is not a closed system. It receives heat from the Sun and from burning of fossil fuels. The melting I am referring to is the "un-naturally" rapid melting of our poles, clearly caused by a change to the environment, clearly not from the annual "transfer" I think you mean(?).

Said transfer occurs, not on an annual basis, but on a continuous moment-to-moment one. The appearance of seasonal changes, owing to Earth's tilt with respect to its orbital plane about the Sun, has no effect on the total Solar irradiation received by Earth, but only on that which given surface areas receive at any particular point in time.

Given that the surface area of the snow/white ice of Antarctica is so much larger and thicker than that of the Arctic, owing in great part to the bulk of such resting on land rather than floating like that of the Arctic, the albedo of the Antarctic is much more stable than is that of the Arctic.
deepsand
3.7 / 5 (3) Feb 22, 2013
(cont.)

The greater variability of the albedo of the Arctic results in more short wavelength Solar irradiation being seasonally absorbed by land and sea, and then being re-radiated at long wavelengths, thus resulting in the aforesaid feedback loop.

And, of course, as Arctic tundra thaws, and methane from decayed plant life is released into the atmsphere, the magnitude of such positive feedback is magnified.
The Alchemist
1 / 5 (4) Feb 22, 2013
Agreed. However, we have seen a great deal of climatic cooling due to melting (see Pacific Northwest temp in the 1990's), and do every year seasonally. Do you know the magnitudes/trade-offs?
And, it is unfair to ask, I know, suggest differences between the world w/o GW vs a world as it is?
deepsand
3.3 / 5 (4) Feb 22, 2013
Agreed. However, we have seen a great deal of climatic cooling due to melting (see Pacific Northwest temp in the 1990's), and do every year seasonally.

That is a weather change, not one of climate.

Do you know the magnitudes/trade-offs?

Of what?

And, it is unfair to ask, I know, suggest differences between the world w/o GW vs a world as it is?

More temperate average temperatures and less volatile weather.
The Alchemist
1 / 5 (5) Feb 25, 2013
That is a weather change, not one of climate.

I was referring to climate, it changed. It is still "weird," it entered into a partial, if false, recovery, but not like the '90s weird.
...trade-offs albeito vs effluence... We actually already answered the question in our discussion.
And, it is unfair to ask, I know, suggest differences between the world w/o GW vs a world as it is?...
More temperate average temperatures and less volatile weather.

Funny, you disagreed with this on the other topic.
deepsand
3.7 / 5 (3) Feb 25, 2013
That is a weather change, not one of climate.

I was referring to climate, it changed. It is still "weird," it entered into a partial, if false, recovery, but not like the '90s weird.
...trade-offs albeito vs effluence... We actually already answered the question in our discussion.

The seasonal changes you refer to have nothing to do with either albedo or Solar influx.
And, it is unfair to ask, I know, suggest differences between the world w/o GW vs a world as it is?...
More temperate average temperatures and less volatile weather.
Funny, you disagreed with this on the other topic.
If that is your belief, then you either misread or misunderstood.

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