Wednesday, April 8, 2009

No Sheet, Ice...

While the sheet ice around the world is apparently melting, the Antarctic ice is growing! My good friend Ken Forden has cornered me again. The other morning at coffee, I foolishly mentioned that the ice on the South Pole was getting thicker and the scientists are watching it closely to determine what it might mean on a global scale. Just so everyone understands, I do believe that the world thermostat is starting to lose calibration. I don't have the knowledge to put it all together. I also want it to be known that it offends me that seasoned scientists do not get funding to try and disprove Global Warming… What’s up with that?

First when floating ice-sheets melt it does not increase the sea level, only ice melting that rests on land will increase the sea level. If you don’t know why that is, go back to reading your funny books, this is not the post for you. If the floating ice-sheets melt, it will allow more warming sun radiation in, and allow more rapidly warming of the polar oceans, which in turn may warm the land ice to the point of melting, thus raising the global sea level. The other thing that it may do is cause more moisture to be added to the atmosphere causing more polar ice to be formed by increased snow fall thus stabilize the warming trend.

I love this scientific stuff with all the thuses and therefores, but alas, I have no atmospheric scientist degrees, so along with being a “Bullshistorian” I also qualify as “Snow Job technician”. My only area of expertise is that I know how to make ice, and it takes 144 BTUs to melt a pound of ice. I do have a refrigeration contractors license to make snow though!

The following article was published Jan 10th 2008, long before the recent ice sheet dislodging in the Antarctic sea. It is from the Christian Science Monitor:

For decades, the vast expanse of sea ice that surrounds Antarctica each winter, and all but vanishes each austral summer, has languished as the Rodney Dangerfield of Earth's cryosphere.

Antarctic sea ice has gotten little respect, especially compared with its top-of-the-world cousin, or with the enormous ice sheets on Greenland and the Antarctic continent. The sea ice is hard to reach. It has little direct effect on people. And the Southern Ocean was not a cold-war playground for US and Soviet submarines, which amassed a wealth of information on changes in Arctic sea ice before the era of long-term satellite observations.

But as a research target, southern sea ice's stock appears to be rising.

Over the past 20 years, southern sea ice has expanded, in contrast to the Arctic's decline, and researchers want to understand why. Many climate-model experiments show the Arctic responding more rapidly than Antarctica as global warming kicks in. But after looking at the latest projections from the Intergovernmental Panel on Climate Change, "Arctic sea ice is well ahead of the models, and Antarctic sea ice is well behind what the models project," says Stephen Ackley, a polar scientist at the University of Texas, San Antonio.

Moreover, recent studies have shown that in key regions off the Antarctic coast, sea ice shows a strong, coherent response to El Niño-La Niña cycles, decade-scale climate swings in the tropical Pacific whose length, strength, and timing may be affected in uncertain ways by global warming. Indeed, outside the tropics, Antarctica boasts the strongest climate response to El Niño of any region on the planet. This suggests strong climate connections and feedbacks among sea, ice, and air in the Southern Ocean that are poorly understood.

Some scientists say trends in sea ice in key spots around the continent may be bellwethers for worrisome changes that could accelerate the melt of nearby land ice, most notably the West Antarctic Ice Sheet.

The overall growth in Antarctica's sea ice over the past two decades masks significant regional declines in the Bellingshausen and Amundsen Seas – the destination for glaciers flowing from the West Antarctic Ice Sheet. Researchers say these glaciers are losing ice to the sea faster than snow is replenishing the ice. Thus, the large regional drops in sea ice could also signal the presence of "a very big threat to glacier ice" on the continent, says Xiaojun Yuan, a polar scientist at Columbia University's Lamont-Doherty Earth Observatory in Palisades, N.Y. The leading suspect: relatively warm water upwelling near the coast as a result of global warming's effect on wind patterns in the region.

To address some of these issues during the Interna­tional Polar Year, which ends in March 2009, scientists are installing a network of buoys off Antarctica's coast. The buoys will track changes in sea ice and measure the factors in air and atmosphere that trigger those changes. Last August, 10 international science groups joined forces on a project dubbed SOPHOCLES, which aims to use the latest information on the Southern Ocean and Antarctica's land and sea ice to improve climate models.

For some commentators, the out-of-sync trends in sea ice at the two poles is evidence that warming isn't global and doesn't deserve the international angst it triggers.

Not so fast, many researchers respond. Northern and southern sea ice shouldn't necessarily act in lock-step. "Antarctic sea ice is such a different animal," says Douglas Martinson, another polar-ice specialist at Lamont-Doherty. Geographic and oceanographic differences – a virtually landlocked ocean in the north versus an open ocean in the south – encourage the buildup of thick, long-lasting, multiyear ice in the Arctic Ocean. Antarctica's sea ice, by contrast, is largely thin and seasonal. In winter, Antarctic sea ice covers an area nearly twice the size of Europe. By the end of summer, it shrinks to one-sixth of its winter extent. These wide swings make it difficult to tease out long-term trends in ice cover there.

The first big advance in monitoring Antarctic sea ice came in 1972, when the federal government launched a satellite with a microwave device to monitor ice 24/7, regardless of cloud cover.

The results were eye-opening, says Claire Parkinson, a researcher who tracks sea-ice trends at the Goddard Space Flight Center in Greenbelt, Md. During three of the first four years the instrument gathered data, an enormous open area in the ice, or polynya, appeared in the Weddell Sea – a phenomenon no one has seen there since. (A grocery-store tabloid had the obvious explanation: that scientists had discovered evidence of an undersea base run by space aliens – heat from the alleged facility had melted the ice. "It was one of our images," says a bemused Dr. Parkinson. "But it wasn't our interpretation.")

Since 1978, the satellite record shows that Antarctica's sea ice has expanded by about half a percent a year. Declines in sea ice recorded between 2000 and 2002 have significantly moderated the overall rise.

These long-term data have let scientists tease out relationships between Antarctic sea ice and natural climate variations, such as swings between El Niño and La Niña in the tropical Pacific. Recent modeling work has given scientists a sense that they are on the right track as they explore the processes affecting sea ice. Dr. Yuan, who uncovered Antarctica's coherent response to El Niño, has developed a seasonal sea-ice forecast model for key regions that scientists now use to plan expeditions.

The ice also plays a key ecological role in the region, some of which bears on the exchange of CO2 between the atmosphere, ocean, and ice, and on cloud formation.

Researchers have found that bacteria and algae that live in the ice trigger the production of huge amounts of dimethyl sulfide, a compound that, when exposed to oxygen, reacts to form aerosol particles around which moisture can condense as cloud droplets. In the ocean, algae and plankton produce the compound. But on the ice, researchers find concentrations some 3,000 times higher than in seawater. And where ice was once thought to keep the ocean from taking up CO2 or returning it to the atmosphere, the picture has grown more complex, Dr. Ackely says. Cold ice does seal in CO2. But slightly warm ice or ice under a little bit of snow begins to flush CO2 out of the ice and back into the air.

Antarctic ice may be melting from underneath

Given the complex role sea ice plays directly or indirectly in the biology and climate of the Southern Ocean region and beyond, its future under global-warming scenarios is of keen interest. Currently, models suggest that through the end of the century, Antarctic sea ice will begin an overall decline, although it isn't projected to be as dramatic as the Arctic's. There, some researchers predict summer sea ice will virtually vanish by 2013, 27 years earlier than previously projected.

A key measurement scientists are trying to make beginning this year involves the mass of Antarctica's sea ice. In the Arctic, ice began to melt from underneath before major shifts in its extent appeared. Thus, measurements of the sea ice's overall mass may uncover changes that aren't readily seen in satellite images.

One factor that could complicate this mass balance is snowfall. Researchers have long known that snow builds glaciers. Two years ago, a team of scientists combined snow-thickness measurements with modeling studies and found that, at least in Antarctica, snow also may build Antarctica's sea ice.

As the climate has warmed, more moisture has made its way to high latitudes. "In the Antarctic in particular, we expect more snowfall," says Achim Stoessel, a researcher at Texas A&M University in College Station, who took part in the study. Simulations showed that with increased snowfall, a sufficiently thick snow layer would push the ice underwater. The seawater in the snow-ice boundary would freeze, thickening the floe.

Some researchers suggest that this process may eventually arrest the decline of Arctic sea ice as well.

more interesting reading

sea ice levels

90% of the ice on earth is located in Antarctica. There is so much ice there you could carve up a block of ice the size of the Great Giza pyramid for every human being on the planet! 98% of Antarctica is covered in ice.

The thickest ice found is in Wilkes Land, where it reaches a depth of 15,669 feet (4,776 meters).


Ernie Branscomb said...

Ice is about seven percent lighter than water, but an ice sheet is fresh water ice, floating in salt water, which is much denser than fresh. As a general rule of thumb, seven eighths of an iceberg is below water, (depending on many factors) so if it rises sixty feet above sea level, it is four hundred and twenty feet into the water. The ice is four-hundred and eighty feet thick.

omr said...

Great post Ernie.

Anonymous said...

Since Ice displaces more area than the subsequent liquid, wouldn't the melting of sheet ice actually make sea level go down? put glass of water in freezer and watch it grow, take it out when frozen and watch the level drop while it melts.

Ernie Branscomb said...

One million pounds of ice will displace one million pounds of water, but water as ice is expanded by 7%, so it rises above the surrounding water because ice is less dense. When the million pounds of ice melts it becomes level with the surrounding million pounds of water that it is displacing, and seeks the same level.

Ice in the freezer is setting on the bottom of the glass. When it expands it lifts it. The same ice floating on water would not change the level of the water. To prove it to yourself, take a large bowl of water and put a large chunk of ice in it. Take a marker pen and scribe a line at the water level. As the ice melts the water level won't change.

Now take the same bowl and place the ice on a board that drains into the bowl, as the ice drains into the bowl it will raise the level of the water.

Same with floating ice, and ice draining off land.

Anonymous, I'm sorry that I said you should stick to your funny books, that was a good question!

samoasoftball said...

Smart post Ernie. I think I will go read the funnies now.......

Ernie Branscomb said...

I'm not trying to disagree with any scientists, I just wonder why they don't let them all speak. It seems like they are trying to bury anything that doesn't agree with Al Gore, Why?

For example: The wilkins ice bridge broke and floated away because it was getting to large. As in:
"Antarctica ice shields are at all-time record high (for 30 years of reliable satellite observation). No wonder it cracks at perimeter. Huge amount of snow precipitated over Antarctica leads to increased ice thickness and accelerated drift. That’s what glaciers do."

Anonymous said...

funny stuff here. hippies went to the arctic to prove global warming and got froze out!

Ernie Branscomb said...

Thanks anon, I made it into a link. Just click on the little blue line. Global warming expedition frozen out

Ernie Branscomb said...

It will be interesting to see how the lastest round of volcanic activity affects the ozone hole. Remember the ozone hole? (different problem than global warming)

Ernie Branscomb said...

Somebody had better tell Al Gore that he needs to plant some trees on Mars also, the Red Planet seems to have a global warming problem too. It's probably being caused by that darn Mars Crawler that man put up there.

Anonymous said...

Solar system warmingis the bigger picture.

Ernie Branscomb said...

Anon, Thanks for the very interesting link.

That post seems to be a theory that all of this heat is coming from another dimension. I really believe that all that’s happening with our “Global Warming” is happening right here. It’s tangible and natural, and all we need to do to figure out what is going on, is some real science, without the emotion and hysteria.

Anonymous said...

Climate change is upon us in a bigger way than science is going to have time to figure out. Science is always running behind what is happening, frequently gets funded by agencies with an agenda, and the public never finds out any truth that might overly scare them.

It would be nice to know the truth and have all scientists have a voice. I scan several websites that bring up the alternative viewpoints to the prevailing global warming paradigm, and how hard it is for those scientists.
The Russians have measured "new intensities" of energy firing up the sun; and as we know solar magnetics rule planetary magnetics and thus the system-wide planetary climate changes so well documented on that last link.
There is no doubt that we have contributed horrifically to atmospheric changes with our pollution, but we are part of a natural cycle that is bigger than our little ol' planet.
The sun has blown many preconceptions and is not behaving according to 'schedule' with the next solar cycle. If our magnetosphere does not recover by the time of the big flares we all know are coming, what does that portend?
My sense is that this big elephant of earthchanges isn't going to be perceived in totality by all the many scientific hands place upon it.
For me, seed and food stores are a very legitimate focus whilst the scientists lead and mislead us.

Fred said...

Nice to know you're not a Believer, Ernie.

Things might be changing a little, now that word is getting out, but I don't know that will dissuade the Believers, and the main stream media.

Eric V. Kirk said...

The sense of urgency does lower the tolerance, particularly where a scientist is suspecting of schilling for industry interests, however, it doesn't help the skeptic's cause when someone like George Will deliberately misrepresents a major study such that it angers its authors.

As for the antarctic ice thickening rather than melting, a googling revealed that it certainly is not being reported that way. Is it media bias, or is the thickening evidence just not given credence in the scientific community?

Ernie Branscomb said...

Yes, but how much is mans fault, how much is cyclical climate change, how much is contributed by the sun? (as evidenced by solar system warming. The south pole of Mars is melting)

There is some evidence that the Sun is entering a cooling cycle that may bring us disasterous cooling.

My next post is about too much Al Gore sience and not enough Dr. William Gray science.