What if the Arctic is the ice cube and the Northern Hemisphere is the glass of water?

Question

No matter how hot it gets, the temperature of a glass of ice water stays at 32F until all the ice is melted. After that the water begins to heat up.

What if things are relatively stable now because all the extra heat is going into melting the ice cap.

What happens when the ice has melted?

Would that be a tipping point in the climate of the Northern Hemisphere?

And what will the consequences be?

Is this talked about in the climate science community?

Answer 1

I'm treading on thin ice commenting on this topic.  As I understand it, the arctic needs a critical mass of ice to sustain  its own climate against oceanic heat fluxes from lower latitudes.    The system is bistable with a change in albedo being the key factor.  External heat fluxes can, and most likely are driving the system to the ice free state.  The SHEBA data from 1998 found significant ice thinning - to 1.8 m average thickness, less than half of earlier readings.  The measurement is indirect: it relies on the change in salinity to infer the volume of fresh water added from melting.  It is quite obvious that once the ice melts, warming will accelerate, at least in the arctic region.  It is safe to predict that a warmer arctic will produce more precipitation in the arctic region.  It is not as easy to predict what the effects on lower latitudes will be.  One theory is that the thermohaline circulation in the North Atlantic Ocean will be disrupted which would negatively affect agriculture and fisheries.

Answer 2

This may have some importance.

But the change in surface reflectivity caused by replacing white ice with blue water is no doubt a more serious issue.

This is bad news in MANY ways.

EDIT - Either neither is a "tipping point" or it's the albedo.  Thermal inertia is not going to be a tipping point.  Just my opinion, of course.

Answer 3

Things are NOT stable now; in the Arctic, things are deteriorating at a very rapid pace. There is observed mass loss in Greenland, as well as the now well-know loss of sea ice in the Arctic Ocean.

You are correct that the phase change from ice to water does provide an additional positive feedback mechanism in the Arctic, as does the albedo effect. These effects are well known among climatologists and included in climate models. These feedbacks are one of the reasons global warming is affecting the Arctic far more than anywhere else on the globe right now. In aggregate, these effects are known as "polar amplification".

Current climate models indicate that polar amplification probably have a regional, rather than global, impact. Temperate continental areas will probably not be much affected.

http://www.springerlink.com/content/kpb6...

Answer 4

The ice cap is not melting!!  But to follow your logic, the AGW backers have a plan.  As the earth warms, Al Gore's 'scientists' have requested them to open the doors of their refrigerators and freezers for ten minutes every day at noon, thus saving the world!

Answer 5

Only 3% of solar radiation is reflected by the surface, the Arctic is such a small percentage of the surface of the planet, and the angle at which sunlight strikes the North pole further diminishes the amount of energy. And if all of that is not enough, the time period that the Arctic recieves any light is short, only a few months, I personally do not believe a tipping point is possible as far as any changes of the northern summer sea ice.

Answer 6

That sounds plausible.

It could be interesting to calculate how many calories it takes to melt 4.4 million cubic meters of Arctic ice, then calculate what that energy converts into as a forcing energy per square meter once the ice is gone.

http://news.yahoo.com/s/afp/20080424/sc_...

The volumes of the Greenland Ice Sheet and ice in the Arctic Ocean were estimated at 2.9 million and 4.4 million cubic metres respectively in September 2007 -- the lowest ever levels recorded, the organization said Wednesday.

Of course the next frozen substance to melt up there could be the methane clathrate deposits in ocean sediments... another possible tipping point.

Answer 7

Nice thoughts, but have a look at this article. It will answer some of your questions.

http://www.thelocal.se/12580/

Once you've read that have a look at this Blog under: Environmentalism vs Conservationism (http://georgewythecollege.blogspot.com/)... Hopefully you'll see a pattern emerge.

Answer 8

Well I'd say this question is applicable to the Arctic Ocean.  A lot of heat (energy) goes into changing the state of water from liquid to solid.  It's true that once all the ice melts, the heat will then go into increasing the temperature of the water.

However, most of the rest of the oceans are already ice-free, and the Arctic Ocean is at a very low temperature, so it will stil be able to absorb plenty of heat without warming up the planet's surface.

I'm sure the change in the Earth's albedo due to the melted ice will be a much larger effect.

Answer 9

I"m not sure of the detail, but several studies have come out recently indicating that the models underestimated the melt rate.  Given the cautious nature of physical scientists, this isn't really surprising. Despite the nonsensical claims that the scientists are alarmist, in reality it's beginning to look like they should be increasing the intensity of their warnings.

http://www.ucar.edu/news/releases/2008/p...

"The rate of climate warming over northern Alaska, Canada, and Russia could more than triple during periods of rapid sea ice loss, according to a new study led by the National Center for Atmospheric Research (NCAR). The findings raise concerns about the thawing of permafrost, or permanently frozen soil, and the potential consequences for sensitive ecosystems, human infrastructure, and the release of additional greenhouse gases."

Answer 10

Yes, this was what I just mentioned in another question.

And, this was also just mentioned in my class on global warming at Ball State University.

When you've got ice melting in a glass of water, does the water level ever rise?  Nope.