Ice-Free Summers Coming To Arctic

rocketjam writes "CNET reports that researchers from the University of Arizona and other universities have concluded that the Arctic will likely see ice-free summers within a century due to the increasing rate of global warming. The melting will raise ocean levels worldwide, flooding coastal areas where a substantial proportion of the world's population live. The increasing rate of ice melt is already having an impact on people and animals in the Arctic. Currently, researchers cannot foresee any natural forces that will counteract the trend."

Comments

Re:And actually, slightly less

[SeanTobin]

Ice is less dense than water, so we might even see sea levels *decline*

Sadly, no. The difference in density between ice and water is manifested in the ice that is above the water line. Grab yourself a tall clear glass, fill it half way with water and add a big ice cube. Mark the water line. Come back in an hour once the ice cube melts and check the water line. It will be in exactly the same place.

Remember, the ability of an object to float is not (directly) related to its density. Its related to its ability to displace water and its mass. The reason submarines float (or sink) is because their shape displaces a greater mass of water than the equivalent mass of water that would fill their volume.

If you take a piece of steel and put it in a bucket, it sinks and raises the volume of the bucket by the volume of the steel. Take that same piece of steel and form it into a boat hull and it will float -- and the volume of the bucket will increase by exactly the same amount even though all of the steel is not submerged.

Re:Won't someone please think of the snowmen!

[Osty]

The only flaw in your logic is that polar bears don't mind being wet.

But not all of the Arctic ice cap is afloat

[erikaaboe]

Here a a few stats from a quick Google search or three-

The total area of Greenland is around 2,175,600 km2 (840,000 sq mi), of which about 84 per cent, or some 1,834,000 km2, is ice cap.

The average thickness of the Greenland ice sheet is over 2000 m.

The area of the oceans is what, 360,000,000 km2?

Melt all of Greenland's ice and is that 10 meters?

Ouch. Er, glug...

more excuses and misinformation

[cahiha]

Finally, the economic change - read as depression - that would come from doing "drastic" things stands a good chance of killing as many people as climate change might.

There is not an iota of evidence that reducing carbon emissions would lead to a depression. Quite to the contrary: it is quite clear that an aggressive move to energy efficient technologies would create new jobs and growth, and would lower operating costs. Scrapping the energy inefficient technologies of today and building new power plants and factories is probably the best thing that could happen to the US economy.

The only people who stand to lose are the people who have large investments in current, inefficient technologies.

First off, we just don't understand what is happening or why.

I'm sorry you haven't been paying attention, but we do understand what is happening and why it's happening.

Unfortunately, if we are in a position where human-added CO2 is the root cause of all of this, we cannot afford the luxury of these kinds of measures. Sure, they might have some effect and that might help. But if we're the cause of climate change, far, far more drastic measures need to be taken right now.

As comparison with other Western nations alone shows, the US could easily cut its CO2 emissions in half without any decrease in its standard of living; quite to the contrary: a serious program to do that would increase the standard of living and create jobs.

Furthermore, if you think you can't "afford" that level of change, what do you think loss of what is probably going to be 50% of the currently inhabited area of the US is going to do to quality of life? Because that's what's going to happen if the trend continues.

Secondly, the third-world countries would bitterly oppose anything that cuts them off from the developed world or limits their exploitation of fossil fuel energy.

They sure do, because the message we are sending right now is that we want to limit them while continuing our wasteful energy use, since our negotiating position is to use our current, wasteful usage as the basis for future budgets. I suspect developing nations would easily agree to a uniform global per-capita energy and fossil fuel budget.

Re:more excuses and misinformation

[Dachannien]

The only people who stand to lose are the people who have large investments in current, inefficient technologies.

That'd be most transportation, utility, and manufacturing companies. And the effect of "losing" is that the cost of production of their goods goes up during the changeover to cleaner production methods. That means that everyone is paying more - a lot more - for the same goods they bought last year, without a corresponding increase in wages. Sales decrease, so profits decrease, so people lose jobs.

All that "extra money" goes into producing equipment that doesn't add anything to the growth of the economy, unless the new methods of production also happen to be more efficient cost-wise (which they aren't, and I think that's the failing in your logic - "cleaner" and "more efficient" don't overlap given technology today, while you were assuming they do).

If, as you say, "an aggressive move to energy efficient technologies would create new jobs and growth, and would lower operating costs," then why aren't developing nations jumping at the opportunity to create this new growth? The reason the US didn't sign Kyoto is because developing nations were made exempt from the conditions of the treaty. They were made exempt because they were viewed as being less able to afford such changes. That flies in the face of your statement that changing technologies is a boon to a nation's economy.

They sure do, because the message we are sending right now is that we want to limit them while continuing our wasteful energy use, since our negotiating position is to use our current, wasteful usage as the basis for future budgets. I suspect developing nations would easily agree to a uniform global per-capita energy and fossil fuel budget.

Of course they would, because it uses a faulty metric that's in their benefit. A better measure of what's being done with one's energy consumption isn't per-capita, it's per-dollar-GDP. With that measure, the US is far more efficient than (for example) China and India, whose ability to claim decent per-capita energy consumption is entirely due to the tremendous difference between their urban middle and upper classes and their gigantic rural farming lower class.

Furthermore, if you think you can't "afford" that level of change, what do you think loss of what is probably going to be 50% of the currently inhabited area of the US is going to do to quality of life? Because that's what's going to happen if the trend continues.

The US eastern seaboard isn't just going to roll off into the ocean all in one day, any more than the US is going to switch to nuclear power all in one day. What's more, it's unlikely that, if coastal flooding is going to occur, the US can do anything to stop it. A possible solution is to slowly begin encouraging people to move their homes and businesses inland (we have a lot of space), while building a newer energy infrastructure (nuclear power) as we make that move. The key here is slowly. As long as things are done gradually, the new jobs created by such a program won't be completely swamped by the jobs lost from suddenly shutting off the old infrastructure.

Re:And actually, slightly less

[Floody]

(assuming that global warming is fact, which all proven scientific evidence shows it's not)

I see. And of course you have links to back up this assertion from respected peer-reviewed journals?

I could understand if you had asserted "mankind is not the direct cause of current global climate change." That's something that is quite disputed by various climatologists; so one could be forgiven for ill-advisedly "picking" a side. The problem though, is that your assertion that "all proven scientific evidence shows it's not" (i.e. global warming is not occuring) is absolute bunk.

That global climate change is occuring is a forgone conclusion, the data clearly shows trending towards average global warming and increased atmospheric co2. Current science is focused on change rates; specifically problems involving sampling history, techniques, statistics and force modeling. Without solid data and working representative models, it's very difficult to put forth a sound cause-hypothesis.

[Gaffen, D et al - Multidecadal Changes in the Vertical Temperature Structure of the Tropical Troposphere, Science vol 287, 18 Feb. 2000]
[Hegerl, G.C. and J.M. Wallace - Influence of Patterns of Climate Variability on the Difference between Satellite and Surface Temperature Trends, J. Climate vol 15, 2002]

Re:Yeah, but

[MillionthMonkey]

Isn't the icecap frozen fresh water? Maybe someone who really knows can tell us if it makes a difference that it is frozen fresh water floating on salt water.

Yes it does matter. While it is generally true that ice does not change the level of the water it's floating in as it melts, it isn't quite true if the ice contains a different concentration of salt (after it melts) than the water.

Here's a thought experiment:

Fill a water balloon with fresh water and freeze it. Drop it into in a bucket of water from the ocean. The ice inside the balloon floats, just like ice that is not in a balloon, because ocean water is 2.5% denser than fresh water, and fresh water is roughly 10% denser than fresh ice.

Now wait until it melts. Soon the water balloon is full of fresh water again. Has the level of the ocean water in the bucket changed? No. There has been a phase transition inside a floating body, changing its density, but as long as 1. it still floats and 2. its mass hasn't changed, the water level in the bucket doesn't care. The only thing that matters is the mass of the object (i.e. the mass of the displaced salt water), and the fact that the object continues to float.

But if you look at the balloon of meltwater floating in the bucket, you'll notice that it isn't totally underwater. The water line forms a little coin-sized circular "island" at the top of the balloon. This is because the bucket has ocean water in it. If the bucket had fresh water, you wouldn't see a part of the balloon sticking up above the water at all. The balloon might even sink.

Now rip the balloon. This will affect the water level. Why? Because when the balloon breaks, that little crescent of water, that was previously sticking up above the water line as an "island", isn't held together by the balloon anymore and it's free to spread across the surface of the salt water in the bucket, raising its level. Really, the salt water level isn't rising- the shape of the floating object (a blob of fresh water) changes, so that there's a layer of fresh water on top of the salt water. But we say that the water level rises anyway.

Again, if the bucket had fresh water, this wouldn't happen, because the balloon would be totally underwater even if it were floating and there would be no "island".

Remember it's only a tiny little bit of water in the island, and the amount is determined by the density ratio between the fresh water and the ocean water. The density of ocean water is about 2.5% higher than that of fresh, and that determines the extent of the balloon's rise above the water level.

This doesn't take into account secondary effects- we haven't taken into account the effects of mixing. The water might shrink a little bit as the brine and fresh fractions mix. (Similar to how mixing one part alcohol and one part water yields slightly less than two parts of 100 proof, because the water and alcohol molecules fit into each other somewhat.) But physical effects like that are not predictable by a thought experiment, and I'm guessing in the case of fresh vs. salt water that they'd account for much less than a percent of a volume change from what we'd expect. So to an elementary first-order approximation, we'd expect the water level of ocean water to rise when fresh ice melts in it.

How much will it rise? Probably by an amount equivalent to approximately 2.5% of the volume of the total fresh meltwater, divided across the entire surface area of the salty ocean water.

Ice on land is far more threatening to global sea levels. The effective meltwater contribution from landed ice is 100% by weight, not just a few percent as with floating ice.

Re:Yeah, but

[Decker-Mage]

No, it is a theory supported by computer models that may or may not have any relation to reality. I've spent my life working in the statistical modeling field and have an extensive background in numerous scientific and damn near every engineering field (see profile) and I can tell you that your model is only a good as whether what it predicts matches reality and exactly how closely.

Current models are all over the place as to what they predict and in almost every case what they predict isn't even close by an order of magnitude to what has happened in that past. Now how are we supposed to rely on models that can't even predict things by a factor of ten? Sheesh, give me a break! Heck, what is even stranger are the journal articles (light reading here) will start with the assumption that global warming is real, find contrary data, and conclude that global warming is real despite the contrary data. This isn't science, it's persuit of funding.

The plain fact of the matter is that to get funding today in various related disciplines to climatology you have to climb on the global warming bandwagon. Sad, but true. It is also interesting that many of the critics of global warming are retired and no longer need funding to persue their interests in the field. In statistics we'd call that strongly correlated.

Now this isn't to say global warming isn't real although I would challenge the notion that it is necessarily related to any man-related activity (that's for another post if anyone is interested). The only constant about the climate on this planet is change and that has been true since it accreted to a planet.