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Ward Hunt Ice Shelf Breaks In Two
heidi writes "CNN has this story on the breakup of the largest ice cap. A permanent feature for the previous 3,000 years, it has broken into two pieces. "The Ward Hunt Ice Shelf, on the north coast of Ellesmere Island in Canada's Nunavut territory, broke into two main parts, themselves cut through with fissures. A freshwater lake drained into the sea, the researchers reported.""
Psst... there are no penquins in the arctic.
RTFA, in particular the following two passages:
Local warming of the climate is to blame, they said -- adding that they did not have the evidence needed to link the melting ice to the steady, planet-wide climate change known as global warming.
"There's a regional trend in warming that cycles back 150 years," Mueller said in a telephone interview. "I am not comfortable linking it to global warming. It is difficult to tease out what is due to global warming and what is due to regional warming."
The Arctic region is warming far faster than the rest of the world (I seem to recall estimates of five times faster), if the rest of the world is indeed warming at all, and its related to natural shifts in water and wind currents. Even if the world temperature was stagnant, this area would still likely be warming, and the shelf would have cracked anyway.
You can never go home again... but I guess you can shop there.
On the geological timescale, 3000 years of solid Ward Hunt Ice Shelf is really just a little blip. For all the worries about human greenhouse gases, we should probably also take a serious look at natural cycles. Only 12,000 years ago, you could walk out to the Farallon Islands outside SF.
Leads? There's a word for the actual cracking and fracturing process "calving", but I think that only applies to glaciers and icebergs.
YLFI
One god, one market, one truth, one consumer.
According to the article, Derek Mueller of Laval University said "It is difficult to tease out what is due to global warming and what is due to regional warming." He didn't call global warming a "myth." He accepted global warming as fact and only said that there was impossible to say whether it, or regional warming, was the cause of this particular event.
Here's an excerpt from the EPA's web site:If the EPA web site under Bush/Cheney (who are pawns of the oil industry) acknowledges global warming as fact, that should give you head-in-the-sand types a clue. Wouldn't it be terrible if we reduced pollution and it didn't fix global warming? Oh the horror!
The ice is already in the water (ocean), so melting it is not going to increase the sea levels. Remember, water expands when it freezes and it goes back down when you melt it. If you don't believe me, fill a glass full of water and put it in the freezer.
The article seemed to imply that this was one of the ice masses that sits on land instead of floating in the water (many do) thus the level would increase. I do not know for sure and am too lazy too look it up for sure.
As the earth is still coming out of its last ice age, we shouldn't be too concerned about global warming. What we should be concerned about is desertification due to the lack of vegitation and depletion of the Ozone. Given the natural course of things, the earth will make big dinosaurs, not silly monkeys who play on computers and bitch at eachother.
well, I sorta agree - the article says they just know it was due to local heating (the area I live in has had two VERY mild summers in a row - we usually have at least a month of 105-110 degree weather - we haven't had a day above 98 in *two* years and average upper 80's to lwoer 90's, about 10 degrees cooler average). that being said many of the emissions aren't good for you - they aggrivate my chronic lung problems (probably cause them), kill off some more sensitive species, and many other things. I would advocate something in between what most seem to want (total reduction, do nothing).
As for the natural outgrowth being big dinno's - I don't really think so. The longest period with anything above single celled organisms (paleozoic) had fairly smallish creaturs - usually about the size of many of ours today - they died out (by far the largest extinction - well over 80 percent of *genuses* - one above species which the loss of a few many seem to think will destroy the earth - died out, though not that that is a good thing either). The next period had the giants - they died out. The only constant has been small bugs and down - they rule the earth, have for millions of years, and will for millions more. So this go around seems to be the silly monkeys bitching at each other as the top of the food chain.
------- Sorry about the spelling, I suffer from two problems. Dyslexia makes it difficult to spell well, lazy makes it
"ozone layer is much healthier than in previous years"
In fact the WMO has realeased findings that say the ozone layer hole above the antartic has this year already reached the record size of 2000.
"The 2003 ozone hole remains similar to that observed in 2000, although more circular and
apparently more stable. The size of the ozone hole has increased from the 25 M km2 reported two weeks ago to
28 M km2, matching the record size observed during mid-September 2000. This is larger than the combined
areas of Canada, Mexico, and the United States, and contrasts the exceptionally small ozone hole last year that
split in two during late September. In recent years, the ozone hole has usually attained its maximum size
during mid-September. However, it is too early to predict with certainty whether the area has peaked this year." - From WMO report 18 Sep 2003.
No, but I do have a PhD in modelling glacial systems during the last Ice Age, so I'll give it a go (appolgies for only using examples from the gulf stream in the N.E.Atlantic, that's the region that I know).
There is a potential risk to the warm surface currents from the loss of floating ice, though it isn't to do with a one-off influx of fresh water. This will rapidly disperse over the ocean and make no perceptable difference.
However, the 'pump' driving the global conveyer is the constant differential melting and freezing at the base of the sea ice. Sea ice is essentially floating fresh water. If you freeze part of sea water into fresh water you are left with dense, cold, salty water. This sinks to the bottom, and then flows south from the arctic. Warm, surface water then flows north to replace it, forming the Gulf Stream (and other similar currents around the world).
Over the last few decades the extent of sea ice in the Arctic has shrunk noticably. There must be a point at which this will have an effect on these currents[1].
It is not clear what the level of sea-ice required to maintain the currents is, nor on quite how the currents will respond (gradually decreasing or simply shutting down). However there is evidence from the sedimentary record of the last interglacial that the gulf stream in the North East Antlantic, at least, switched on and off a number of times, and that the switch from 'on' to 'off' was very rapid.
There is thus the possibility that current climate trends will result in a situation in which the flow of warm water to the N.E.Atlantic may cease (or dramatically reduce) over a timespan of years or decades, producing dramatic climate changes in north Western Europe (especially Iceland and North Norway, but Britain, Ireland and France are also major beneficaries of the Gulf Stream). The lack of transfer of heat from the warmer regions may also result in higher sea-surface temperatures in those regions, which in turn could provide more energy for severe bad weather and hurricanes. There are futher possible effects from the lack of the cold water current. These are important in carrying oxygen around the oceans, and when they upwell against continental shelves they bring nutrients from the deep ocean to the surface, producing rich fishing grounds.
[1] It is also, incidentally, having a major effect on polar bears, which rely on sea ice in their hunting.
"The ice is already in the water (ocean), so melting it is not going to increase the sea levels."
I'm not sure if you're just talking about this ice shelf, but there's a helluva lot of ice sitting on Antarctica (ie land).
I'm giving up on debating global warming on Slashdot, it seems just about everyone is convinced its bunk. With the weather getting more and more extreme, could you at least understand why we are worried?
Well, I just wanted to make everyone aware of the new distributed project - www.climateprediction.net.
Whether you agree with the theory of human caused global warming or not, with this you can help getting the world scientific community more accurate climate models.
Unfortunately only a Windows client available at the moment, but a Linux one is in development. Personally I think this project and the
Folding at Home distributed project are much more deserving of peoples' clock cycles than Seti or distributed.net.
Cheers,
Lars
MEDIA KIT: Debunking Pseudo-Scholarship: Things a journalist should know about The Skeptical Environmentalist
Being bitter is drinking poison and hoping someone else will die
You, sir, are so wrong it hurts my eyes to read!
Place a big chunk of ice in a container and fill it with water. Then sit back and see how the melting of ice does not rise the water level. Then get back to your physics books and figure out why it doesn't.
The problem with global warming is not with floating ice. It's with Antarctica where ice is sitting on the continent. Melting of that ice will rise the sea levels.
That's false even by the scientists' own admission. The models are not predictive. Part of the obvious falsity of the claims made by the IPC is that the computer models project warming at the surface, and in the upper atmosphere. The upper atmosphere has actually cooled. If the model is not predictive - it is worthless. The models can not even manage predictiveness for known past climate events.
There are a lot of temperature graphs that show increases in the last 100 years. There is also a nice graph showing an increase in CO2 levels from coal and oil burning. That's not just a coincidence, given that the physics behind the temperature increase is pretty straightforward (greenhouse effect). in fact, in order for surface tempertures not to rise with increasing CO2 levels requires some rather fancy footwork; you have to invoke the existence of various negatiuve feedback cycles, like increased cloudiness (which may actually have a net warming effect after all) etc. The radiative-tranfer physics behind the greenhouse effect is a lot more solid than our understanding of cloud formation.
To state that the increase in CO2 is undeniably causing the increase in temperature is just bad science.
In science nothing is "undeniable". However, some things are more or less plausible, likely, belivable etc. A good scientist working on something realitively new will always hedge. But sooner or later the evidence starts to build up to the point where only cranks deny it. Hence most scientists think e.g. evolution is pretty solid. The same goes for general relativity, QED, etc. Climate change due to increased CO2 levels is getting to be such a strong theory (or so says the NAS here and here, and the IPCC).
There's no evidence to back it up.
That is simply hogwash. There is a lot of evidence for a coupling between CO2 and temperature rise. It may be challenging to directly link CO2 to this particular ice shelf, but I ask you this: if global and regional temperatures are rising due to increasing CO2 levels, are you surprised that we are seeing more ice melt?
We need experiments and more data before any sound scientific conclusion like that can be made.
We always need more data (I'm a scientist after all), but we have the basis to act now, and the longer we wait the harder the problem will be.
In my list I mentioned at least four very plausible reasons for global temperature rise that do not depend on an increase in CO2.
I'm going to hope it is the "alien death ray", personally. Seriously, though, greenhouse gases are about the only plausible ones in your list. The Earths core is pretty stable in it's heat output, not to mention that it's about a factor of 100 lower than the heat input from the Sun. To raise temperatures by the observed amount you'd have to increase the core heat output by a factor of about 4. Not likely.
Is the Sun putting out more energy on some long period that we don't yet know about?
First of all, there is not a lot of evidence for such a change (we can measure the solar constant afetr all). Second, you'd then have to explain how the increasing CO2 wasn't causing a rise, while at the same time the Sun caused a rise that coincides very nicely with the CO2 increase.
The rest of the list is just silly.
Human genome = 3 billion base pairs = 6 GBit. Windows + Office = 20 Gbit. Which is more impressive?
Reality check:
I can't seem to find direct figures on CO2 release from Krakatoa. However, we can do a ballpark estimate. Various sources state that it ejected 5 cubic miles of material. Other sources indicate that magma saturated with volatile compounds holds up to 6% compressed gasses, most of it water. Let's assume that Krakatoa's magma was 2% CO2. So that's 2% of 5*1609^3 = 416 million cubic meters of CO2. At 1070 kg/m^3 (liquid phase), that's 445 megatons of CO2.
Even if my estimates are off by a factor of 10, Krakatoa spewed no more than a few thousand megatons of CO2.
As for human emissions, the estimates I find are 6,500 megatons of carbon per year (about 1 ton per person on the planet), which when combined with oxygen make about 24,000 megatons of CO2.
So you say that the Krakatoa eruption dwarfs 100 years of human activity, and I calculate that Krakatoa ~== 1 week of human activity. My estimates would have to be off by 3-1/2 orders of magnitude if your statement were correct. If you can find any numbers to back up your assertion, I would be happy to see them.
According to the BP statistical review, June 2002,
global consumption of liquid fossil fuels comes to
5595 KBbl/diem gasoline, 9247 KBbl/d. kerosene,
4873 KBbl/d. fuel oil, or 264, 435, and 230 MT/an,
respectively, for a total of ~929 MT/an. The
remainder of liquid fossil fuel production is
consumed by manufacture of materials or consists
of loss. Accepting BPs loss estimates, and assuming
all losses are gassified, that's 220 MT/an.
Coal consumption is 71.0% and natural gas is 60.0%
oil equivalent. To be generous, I include
production and refining losses to get a total
global annual carbon injection of
(1.00+0.600+0.710) * (220+264+435+230) MT
which comes to 2654 MegaTonnes annually, or
less than 443 Kg per person, annually.
This represents 90% carbon, which is 12/44 of
C02, for a total CO2 injection into the carbon
cycle of 1.46 metric tonnes per annum per capita,
or 8,750 MT/an total.
As you say, Krakatoa might conceivably have
emitted a few thousand megatons, but the human
emissions at that time were vanishingly small
in comparison to their current levels, so that
the eruption probably injected more CO2 than all
human activity during the *preceeding* century,
but in my estimation certainly injected an order
of magnitude less than the human activity during
the *following* century.
Perhaps it was equivalent to a century of human
injection at the rate prevailing at the time
the original estimation was made, and this statement
was later carried forward, and quoted on slashdot,
long after it was no longer accurate.
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