"Major Arctic sea ice melt is expected this summer." What do you think?

Question

http://news.yahoo.com/s/ap/20080502/ap_on_sc/on_thin_ice;_ylt=AhUZeblPMLgTfyl6L_MaBWKs0NUE

Answer 1

Wow, yeah, ice melting when it's warm, warm when it's summer...  Dunno if I can wrap my head around it.

Supposed to snow tonight here!  Fun!

Answer 2

I sure hope the snow melts today from the Colorado blizzard they had yesterday

Answer 3

I think it is baseless, especially considering that a NASA study indicated that last years record low Arctic sea ice was caused by a change in atmospheric circulation and not by any change in radiative transfer of Earths atmosphere. It is also laughable that extreme cold Antarctic atmospheric conditions modulate the size of the ozone hole, not the other way around.

Answer 4

Interesting, I would have expected the worst melt to come in 2009 after the current La Nina cycle fades a bit more.

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http://news.yahoo.com/s/ap/20080502/ap_o...

...while solar radiation and amounts of greenhouse gases in the atmosphere are similar at the poles, to date the regions have responded differently, with little change in the South, explained oceanographer James Overland of the National Oceanic and Atmospheric Administration.

What researchers have concluded was happening, was that in the North, global warming and natural variability of climate were reinforcing one another, sending the Arctic into a new state with much less sea ice than in the past.

"And there is very little chance for the climate to return to the conditions of 20 years ago," he added.

On the other hand, Overland explained, the ozone hole in the Antarctic masked conditions there, keeping temperatures low in most of the continent other than the peninsula reaching toward South America.

"So there is a scientific reason for why we're not seeing large changes in the Antarctic like we're seeing in the Arctic," he said.

But, Overland added, as the ozone hole recovers in coming years, global warming will begin to affect the South Pole also.

The briefing covered data being reported in a paper scheduled for publication next week in Eos, a journal of the American Geophysical Union.

Overland said he used to be among those skeptical about the effects of global climate change. The new findings, which he termed "startling," were developed at a recent workshop, he said.

There is agreement between weather observations, the output of computer climate models and scientific expectations for what should happen, added Francis.

All the evidence points toward human-made changes at both poles, she said, a conclusion that "further depletes the arsenals of those who insist that human-caused climate change is nothing to worry about."

Answer 5

The skeptics will say something like "of course alot melted this summer because so much froze during the cold winter".

Answer 6

You asked what I think so I'll tell you.  First, whether glaciers are advancing or retreating, they still have an annual cycle.  When they retreat, it mainly means that after a summer melt they don't replace all the ice that's gone.  That's still going on at both poles, but in the Arctic we have some new things we've never seen before.  One is that as the Ice pack melts and begins to move around the bottom ice melts so the whole thing begins to float.  It then begins to slide towards the sea much faster, like a thousand feet a day or more in Greenland.  The real melting happens after chunks break off in the ocean and float away, but that makes it go a lot faster than the few inches a year that it used to be.  The other "new" thing is as the ice pack melts gigantic lakes form, going very deep into the ice.  They expand and grow until finally there is a breach in the way and millions of gallons of water pour out into the ocean.  Last year was the biggest melt ever seen, and I expect this year to be bigger.  It appears this will be the situation until all the arctic ice is gone a few years from now.  The ocean temperatures can be expected to not rise until after the ice has melted and equilibrated with the rest of the ocean.

In the South the situation is different.  The Arctic ice mostly floats on water, so only the part above the waterline is added to the sea water volume when it melts (and the parts on land, like Greenland).  In the South, almost all the ice is on land.  Most of the continent is a high flat plateau, and the ice is miles thick.  That part won't be going anywhere for a while.  The western part of the continent is lower, and slopes right down to the sea.  There is a sort of ridgeline between the two.  On the west, there are two enormous bays, or gulfs, both covered with ice shelves, or sheets, that are melting fast.  That's the area to watch.  In the antarctic summer (northern hemispheres winter)  the ice shelves have been melting similar to the ice in the Arctic, with chunks breaking off and floating away to warmer latitudes.  In the past 2-3 years these chunks have suddenly increased in size to the size of a New England State.  As this goes on the shelves grow more and more unstable and are expected to at some point break up entirely, and float away.

Those shelves are very important for several reasons.  One is that several large cold ocean currents originate beneath them.  Some connect to the "global conveyor" of warm and cold currents that circle the globe mixing warm and cold water and moderating the climate.  Without the cold ocean currents nobody knows what will happen to the conveyor.  At the very least it will be all warm water.  One branch of the antarctic currents doesn't connect to the conveyor, but instead dumps directly into the Indian ocean.  Without this current the Indian Ocean would just continue to warm, as it has no other cooling current.  This would drastically affect the climate of India and Southeast Asia.

The other way the ice shelves are important has to do with the inland ice.  Because the land slopes toward the sea, and because the ice forms inland it is thicker as you move inland toward the pole.  As a result it is also heavier, and the force of gravity makes it want to flow toward the sea.  Within the landlocked ice there are riverlike features, sometimes called streamers, or runners.  These flow the course of natural valleys and similar geography.  They move toward the sea faster than the rest of the ice, often as much as 1000 feet a year.  They flow to the two large bays, or gulfs, from hundreds of miles inland.  As things have been for the past 50 million years, when they reach the sea they are stopped by the ice shelves.  They can't move forward, so the ice just thickens at that point, and pressure is exerted for the shelves to grow further and further out to sea.  As the ice shelves melt and break off, they offer less resistance to the ice moving from the interior.  When they are gone, the flow from the interior will be unimpeded at 1000 feet per year, or more likely, speed up.  This will increase the rate at which ice is lost from the interior.  Whether this will include the eastern ice we don't know.  My guess is some, but not all.

So the likely scenario is the arctic ice and the west antarctic ice will continue melting at about the current pace.  The ocean temperatures will stay stable, which will cause the atmospheric temperatures to stay stable, or rise very little.  Once the ice shelves are gone, the land ice will start to move into the sea more rapidly, as Greenland is doing now.  With the arctic ice and the antarctic ice gone the amount of new cold water being added to the oceans will be reduced to only the antarctic land ice, melting at a slower rate.  Mixing will continue, and the water temperature will begin to rise, followed by the atmospheric temperature.  That will accellerate the loss of the western inland ice, and begin the loss of the eastern ice.  Around that point, some populated equatorial and temperate regions will have become uninhabitable.

Answer 7

Gee, summer......ice melt....who would've thunk it.

Even the arctic warms up in the summer time.  One way to look at it is that we go through the entire global warming/global cooling cycle once every 365 days.

Answer 8

Better work on that backstroke.

Answer 9

I am not worried about anything major happening.  I know God will never destroy the world again with water, it will be fire. Things go in cycles, it gets hotter and it gets colder. Nothing we can do. Strange all of this is coming up during election year.

Answer 10

Uh...der...summer...heat...i wonder what will happen.

Answer 11

I really am having a hard time figuring out why people are fretting over a little ice melting.  It happens every year in the summer, some years more than others.  In 20 years, I wonder what these ice huggers will be remembered as, the gullible or the prophets.  My bet is the gullible.

Answer 12

YOUR LINK SOUNDS MORE LIKE A COMMERCIAL OF SKEPTICS= http://www.socyberty.com/Activism/First-... IS THE FIRST STEP TO STOP GLOBAL WARMING THATS STARVING THE WHALES.

Answer 13

when you look at how much of it is one year ice after last years massive melt, and all the perrenial ice that blew out into the atlantic, its not surprising.

add in the water warming faster in the arctic than anywhere else....

one chap described this winter's ice as 'like a stage set'.

http://www.nytimes.com/2007/10/02/scienc...

http://www.eurekalert.org/pub_releases/2...

Answer 14

I don't think the actual article matched the tone of the title. I'd be quite surprised if this years melt tied or beat last years. Things tend not be to quite that linear.

Looking at the trend, 2007 was a huge decline below the trend-line:

http://nsidc.org/news/press/2007_seaicem...

I think we can confidently say that the trend will continue to drop (and possibly accelerate), but it could be another 5 - 10 years before we exceed the 2007 record.