Slashdot Mirror
NASA Study Shows Antarctic Ice Sheet Shrinking
deman1985 writes "A recently released NASA study has shown that the Antarctic ice shelf is shrinking at an alarming rate of 36 cubic miles per year. The study, run from April 2002 to August 2005, indicates that the melting accounted for 1.2 millimeters of global sea level rise for the period. From the article: 'That is about how much water the United States consumes in three months and represents a change of about 0.4 millimeter (0.01575 inch) per year to global sea level rise, the study concluded. The study claims the majority of the melting to have occurred in the West Antarctic ice sheet."
If you believe in global warming the terrorists win
West Antarctica was pretty dull anyway. At least East Antarctica is safe.
That would be 0.4mm a year on top of the other sources of rising sea water.
And assuming a constant, non-accelerating rate unlike what is currently being observed in greenland.
But good job trying to minimaze the problems we face today.
A blog about stuff.
because of the properties of ICE vs Liquid Water the melting of the Artic ice sheet actually lowers water world wide.
It's moments like these I wish Archimedes was alive and reading Slashdot.
"I've got more toys than Teruhisa Kitahara."
It is going to continue getting hotter. Everything making it hotter is continuing to operate, nothing is stopping. The last 5 years are among the hottest in human history. The ice is melting faster than before, faster than predicted. The melt accelerates further melting. When the West Antarctic Ice Sheet and Greenland have melted, the seas will be 35' higher, which will be the end of the world for the majority of humans, who live near the coasts or will be invaded by the displaced people fleeing the rising seas.
You're insisting on denial of the catastrophe because you made up your mind before the situation was so obviously bad. You were wrong then, you're wrong now. The least you could do is drop the denial, because that's the main obstacle to people working together to lower the risk that the end of the world is coming.
Regardless of whether you want to admit that humans caused the warming, the fact is that our actions could slow or halt it before it destroys us.
--
make install -not war
Amenties include:
*Refurbished Y2K model# 1D10T"
Power to the Peaceful
"Why can't people understand CYCLES? and 'GET OVER IT'..."
Because there is no conclusive evidence that this is only part of a cylce.
As an evironmental scientist, my "gut" feeling is that this IS a part of cycle but being exacerbated by human factors. Look at the ice core and other geologic indicators: none of the planetary heating/cooling cycles ever recorded occcured with anything approaching this intensity. They were gradual, over thousands of years. We've seen millenia worth of warming in the last ~120 yrs.
Regression analyses of almost any factors you care to name show a near-perfect correlation with the humanity's industrial emissions. Cooked up examples in introductory statistics textbooks aren't any better.
Blindly chalking everything up to cycles is dangerous - what if that's incorrect? What do we lose by reducing hazardous emissions and pursuing alternative energies? Nothing, that's what. We potentially save the planet and reduce the corrupting inlfuences of the petrochemical industry. And if it ultimately has no effect on the environment, that's a price I'm willing to pay. What you suggest is a gamble that humanity cannot afford to make.
What I don't get is how you can even identify a West Antarctic ice sheet? Isn't Antarctica roughly a circle centered on the pole? So, isn't every ice sheet the West one?
Free Conference Call -- No Spam, High Quality
because of the properties of ICE vs Liquid Water the melting of the Artic ice sheet actually lowers water world wide..
Errr... WHAT?
Time to do the math again, I guess. Every now and then this bit of ugly science rears its ugly head.
Useful numbers:
Density of Seawater: 1025kg/m^3.
Density of Freshwater: 1000kg/m^3 (rounded up from 999.98 at freezing point)
Density of Ice: 916kg/m^3 [same source].
Things to know:
The vast majority of icebergs are not frozen seawater, they break off from land glaciers and float out to sea.
Buoyancy tells us that X will float in Y if X displaces a volume of Y where the mass of the displaced volume equals the mass of X.
Hollowed out shapes can contain more volume than a solid block of mass (this is why metal boats float).
So, lets say we have a solid, convex iceberg floating in an ocean ever so slightly above freezing, consisting of exactly 1025kg of ice right about to melt. To float, this iceberg must displace 1025kg of saltwater, which by sheer coincidence is exactly one cubic meter. Thus, when this iceberg broke off the glacier and fell into the water, the sea level increased by the height of one cubic meter spread out really thin across the entire surface. If you lifted the iceberg out without letting it melt, that one cubic meter would come back and fill the hole where it was.
Naturally, the sea being ever so slightly above freezing and the ice being ever so slightly below, the ice absorbs heat from the ocean and melts. Thanks to wonderful conservation of mass, we know we now have 1025kg of fresh water at ever so slightly above freezing, with a density of 1000kg/m^3. Thus, we have 1.025 cubic meters of fresh water to fill that 1 cubic meter hole where the iceberg used to be.
So because the iceberg fell into the ocean and melted, the sea level is now 1.025 cubic meters (spread out real thin over the entire ocean) higher than it used to be. Even if the ice started in the ocean (as in the Arctic), it's still 0.025 cubic meters high! It gets worse if the ice is sitting on the bottom of the ocean (then there is more ice than displaced water)! Even if you assume that the seawater is less dense in the Arctic (a fallacy, as the freezing action actually increases the saline content of the water around the ice), as long as the density of the seawater is greater than the density of the water you get from melting the ice (almost always freshwater), you will get an increase in sea level from melting the ice.
Incidentially, arctic ice is not all frozen seawater, much of it is from precipitation falling on top of the frozen seawater, so you can't even claim that the water in the ice came directly from the ocean in the first place (not that that claim would really help any, because that water has been locked up for thousands and thousands of years, returning it to water would definitely raise the ocean level beyond anything in written history). Plus, once the water is liquid and continues to heat, it will continue to expand: at 30C freshwater is only 995.65kg/m^3.
Since I whipped out the math anyway, 1025kg of ice is 1025kg*(1m^3/916kg)=1.119 m^3. Since it's solid and convex we know that there must be 0.119 m^3 of ice above sea level. This shows that roughly 10% of the 1.119 m^3 of ice is above sea level, thereby supporting the old adage that 9/10 of the iceberg is below the waterline.
If I have been able to see further than others, it is because I bought a pair of binoculars.
What is dangerous is jumping to the conclusion of why it is changing. If we were to "accept" the opinions of a few climatologists that human nature is what is causing the climate change...
I beg to differ. In a recent study by Science Magazine, a search of the ISI database on the keyword "climate change" yielded 928 peer-reviewed papers, NOT A SINGLE ONE OF WHICH disputed the conclusion that global warming is caused by man-made changes to the atmosphere.
The so-called "debate" only exists in the popular press, where (in a misguided attempt to provide "balance",) 53% of articles express doubt on global warming. Red-staters may not like this article very much either, but I challenge any of them to find a respectable counterargument.
Weeks of coding saves hours of planning.
You should see what Bush had to say about the global warming news.
It may be that we will come out in a world better suited to our soon to be 9 billion human population. It may be that much of the planet will become uninhabitable or no longer arable. What is evident is that the majority of people who bother to consider the possible outcomes seem to think there will be one diasterous consequence and that somehow we'll all pull together to get things under control. It's as if something like Katrina is envisioned, but it's likely to be very complex and detrimental on a number of fronts. The truth is our ability to maintain our existing infrastructure is very limited.
A washed out bridge can bring traffic to a halt on a major highway. Imagine a warming world with increased sever storms, washing out roadways and rail lines, while bringing down power lines. Ice storms could bring the whole eastern seaboard to it's knees because the existing powerlines aren't able to carry the weight of the ice.
The emergency contingency plans and resources in place were slow and sloppy in reacting to Katrina. Play whatif with three or four hurricanes or sever storms pounding on the Gulf of Mexico and turning to ice storms in the north.
In the late 90's the American scientist Edmund Wilson postulated that for the existing world population to enjoy the life style of America today on a percapita basis would require the resources of another 5 worlds. Recently a conservative thinktank worked out that for China and India to live at the level of America today we would require the resources of another two worlds. So we have a world awash in weapons with a population ontrack to hit 9 billion in a biosphere showing signs of undergoing radical systemic change.
You should ridicule the alarmists. You should make jokes because it looks like it's going to get ugly fast.
"Academicians are more likely to share each other's toothbrush than each other's nomenclature."
Cohen
Wrong. There is widespread scientific consensus on the existence of global warming, and that human activity is contributing to it. A 2004 Survey of 928 peer-reviewed research articles related to climate change from 1993-2003 concluded that:
"Many details about climate interactions are not well understood, and there are ample grounds for continued research to provide a better basis for understanding climate dynamics. The question of what to do about climate change is also still open. But there is a scientific consensus on the reality of anthropogenic climate change. Climate scientists have repeatedly tried to make this clear. It is time for the rest of us to listen."
Noteworthy is that none of the articles dissented with the consensus opinion. None of them. Not much of a controversy, at least among people who know what they are talking about.
If you are going to propose a hypothesis that CO2 emissions are harmful, you have the burden of proof, not the other way around.
Why? Because humans burning fossile fuels in great numbers is the natural state of affairs on earth, and the risk from any deviation from it should be thouroughly assessed before starting?
Reality check: serious CO2 emissions by humans have started 150 years ago. Your sentence should be turned around: "If you are going to propose a hypothesis that CO2 emissions are harmless, you have the burden of proof, not the other way round".
"When I first heard Daydream Nation it quite frankly scared the living shit out of me." -- Matthew Stearns
Considering that Earth's climate is something with a huge momentum, changing its course later on may or may not be an option. That's why ignoring even the _possibility_ of irreversable and catastrophic climate change risks missing a crucial window of opportunity, or even a less-crucial window of low-cost opportunity. Now is the time when we have a good chance of getting by with relatively painless, limited, and non-intrusive measures, provided we are prepared to make them _structural_.
And low-cost, low-tech opportunities for savings abound. Just think of home insulation, use of solar energy to reduce the energy needed for airconditioning and general climate control in buildings, use of heat pumps to lower energy requirements of climate control, and (heaven forbid) energy efficient cars etc..
But even those are often not economically viable because the price of energy is so low in the US. To be fair, why bother with complicated gizmos when you can just have this big cheap wasteful-but-effective-and-reliable thingy installed that will set you back only about 100$ a year in energy bills? Unfortunately our situation is known as a prisoners dilemma. If any business takes the time and effort to conserve energy, it can't spend that time and effort on its core business, and any resulting cost increase (or failure to drive costs down) in its products will be punished by the market.
This is why governments were invented. Tho break this deadlock of short-term interests and impose measures on _everyone at the same time_ that make the long-term needs felt. And yes, the primary instruments are often know as laws and regulations, and and the only ways of internalising external cost (as it is called) are known as taxes or levies. Nobody likes them (they hurt), but sometimes you have to have them. I personally think this is one of those occasions.
Taking the risk of missing either a "hard" window of opportunity or a "soft" one, purely for contraryness, short-term financial reasons, inertia, convenience and short-term political gain is both irresponsible and irrational.
It's telling of the American mindset that decades of energy-related research have been marginalised, downsized, cost-cut and generally ridiculed as idealistic but impractical, and certainly unneeded.
It's equally telling that the prospect of irreversible catastrophic global climate change is dismissed while the certain prospect of price hikes for gasoline (to say the levels of Europe) and *gasp* dependence on foreign powers is enough to galvanise an administration into a (fairly marginal) energy research programme.
Well ... at least it got their attention now ... in a way.