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100-Sq.-Mile Ice Island Breaks Off Greenland Glacier
suraj.sun sends word of a 100-sq.-mile (260-sq.-km) ice island that broke off of a Greenland glacier on Thursday. "The block of ice separated from the Petermann Glacier, on the north-west coast of Greenland. It is the largest Arctic iceberg to calve since 1962... The ice could become frozen in place over winter or escape into the waters between Greenland and Canada. ... [NASA satellite] images showed that Petermann Glacier lost about one-quarter of its 70-km-long (43-mile) floating ice shelf. There was enough fresh water locked up in the ice island to 'keep all US public tap water flowing for 120 days,' said Prof Muenchow." The Montreal Gazette has more details and implications for Canadian shipping and oil exploration, along with this telling detail: "the ice island’s thickness [is] more than 200 metres in some places... [or] half the height of the Empire State Building." The NY Times has a good satellite photo of the situation.
It is approximately the on the same scale, to the oceans, as that of a candy bar in a swimming pool.
And it will cause almost as much excitement.
This issue is a bit more complicated than you think.
Oh, I just love this argument. It's based on the fact that arctic sea ice is declining to unprecedented levels according to studies using every piece of data and proxy data known, as documented in dozens of peer-reviewed studies, but at the same time, Antarctic ice is increasing, and at times, the combined average is higher than the previous combined average. Never mind that Antarctic sea ice increase is a *forecast* of AGW due to the increased snowfall and increase in flow rates of its glaciers, while Artic sea ice is declining, as expected.
The argument can basically be summed up as this:
"I like your Christ. I do not like your Christians. Your Christians are so unlike your Christ." - Gandhi
Right, because global warming predicts that all weather will cease to exist, right?
Seriously, what sort of idiot thinks that there will be no randomness from year to year? Climate is about *averages*. And the trends are clear.
"I like your Christ. I do not like your Christians. Your Christians are so unlike your Christ." - Gandhi
The average temperature at the peak of the last glaciation was 8-9C colder than the modern era. In one century, the "business as usual" scenario will lead to over 5-7C warming (our current rate of rise is about 2C per century, but not only are emissions rising, but we're currently having to overcome the planet's thermal inertia).
It's not *that* the temperatures are rising that's the problem. It's the *rate* that's the problem.
"I like your Christ. I do not like your Christians. Your Christians are so unlike your Christ." - Gandhi
From TFA:
http://dotearth.blogs.nytimes.com/2010/08/07/vast-ice-island-breaks-free-of-greenland-glacier/
> Petermann is a sleeping giant that is slowly awakening.
> Removing flow resistance leads to flow acceleration.
Basically, this means flow acceleration would speed up erosion of the corners that "landlock" it relatively quickly. Pressure caused by the increasing flow on the parts that do the "landlocking" could also lead to the iceberg breaking into smaller parts thus making it easier to make it to the open water.
Everything I write is lies, read between the lines.
Global warming refers to a general trend. Even if there is global warming, it can still be colder one year than the other, even though the trend is upwards.
The fact that the temperature was warmer on average for several years in the past, could mean that there was more melting, causing ice to be more brittle, or more likely to break when ice re-froze.
In other words, damage could have happened to the glacier over time that caused certain regions to be less stable or less sustainable, even if the pattern for a later year had been colder.
It's not 2010 that matters alone, it's the group of large number of years.... 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015
You can't just take one year out of all those, and use temperature or other changes during that one year to show that there IS or IS NOT atmospheric gas pollution causing global warming, or if global warming did or did not result in an event.
The mass might break off due to past global warming, even if it happened to be colder this year.
The mass might break off even if there is no global warming at all.
Global warming might effect the probability that large pieces break off of glaciers over time, rather than being a single cause of any deteoriation event.
So anyways, the fact temps cooled alone is no proof that global warming did not result in this.
Volume of a 15 x 2 x 3 cm chocolate bar: 9e-5 cubic metres
Volume of an Olympic swimming pool: 2.5e3 cubic metres
Volume ratio is 1 : 2.78e7
Total volume of the oceans is 1.3e18 cubic metres
Iceberg volume, in the same ratio as chocolate bar : swimming pool, would be 4.68e10 cubic metres
If the iceberg is 200 m thick, then the area is 234 square kilometres.
The area of the iceberg, according to the article, is 260 square kilometres
O.o
You, sir, have astounding powers of estimation.
You have an ID that clearly shows you have been around for a long time. Yet you post such an inanely stupid comment. It's like rationalizing that while humans are directly causing thousands of species to go extinct every year (true), everything will be OK because in a few million years they will just evolve again. Do humans have life spans of 1000s of years? We each live on this planet for a finite amount of time. We now find that we are causing changes to accelerate which will cause us great challenges. Where is my arranging deckchairs on the Titanic analogy, I need it again!
As a reference:
The author, of course, conflates finding crops growing in modern Greenland to assuming that they could have grown back then, but notes the strong evidence that little, if anything, was ever successfully grown back then but hay and possibly limited amounts of flax (and the only evidence for that is pollen studies, which failed to turn up traditional food crops). Contemporary writings noted that most Greenlanders lived their whole life without ever seeing wheat, a piece of bread, or a mug of barley beer. The earliest settlers reportedly tried growing barley, but there was virtually no success.
"I like your Christ. I do not like your Christians. Your Christians are so unlike your Christ." - Gandhi
First off, the frog thing is just a myth. Second, life can adapt, but only with time.
"I like your Christ. I do not like your Christians. Your Christians are so unlike your Christ." - Gandhi
Let's nuke the bastard. That'll take care of it. It worked in Armageddon.
Bibo Ergo Sum.
The extent of the ice cap is not the only way to measure the ice cover in the arctic. Probably more important is the quality and the volume of the ice at the polar cap.
By the way, ice 'extent' is different than the 'area' covered by ice. 'Extent' is what is often quoted, not 'area'. Extent is measured like this: If a grid square being examined has more than 15% ice then it is considered ice covered. So if you had two grids being examined of say 10 sq km each, one being covered 80% by ice and the other being 16% covered by ice, the measurements would say that the ice extent or extent of ice coverage is 20 sq km, when the area would be more like 9.6 sq km. Because this is measured by satellite, grids for study are normally more like 25 or more sq km. Argument can be made to use extent over area since sometimes melt water over ice can be interpreted by the analysis software as being open water. Not always but sometimes; so they use extent to be on the safe side.
What many leave out is analysis of data from satellites that provide measurement of ice thickness. The linked web site addresses this somewhat. I have read about and seen information mentioned more and more on this for at least the last five or six years (and to be sure, the real experts have been looking at this for years). It looks like even if the ice extent is greater this year than in 2007, it is still about 1.6 million sq km less than the 1979 to 2000 average; and more importantly, the current volume of arctic ice is the lowest on record.
-- I ignore anonymous replies to my comments and postings.
It's not fair that these guys took the word "skeptical" which is supposed to mean "don't believe in Global Warming, Evolution, Keynesean economics or Obama's birth certificate and made a site that takes global warming seriously.
That's bait and switch right thar.
You are welcome on my lawn.
Out of curiosity, can you point to any specific individual who wants to have it both ways, or is the problem that both sides are composed of a small number of rational people, and a lot of screaming loons?
"Who is the Journal of Quantum Physics going to believe?" --Stephen Hawking
Gets used here.... alot.
Arguments both for or againsts a scientific problem should be framed as defendable proofs.
We know that the top of Earth's atmosphere receives 342 watts of energy, in the form of sunlight, per square meter. Note that 107 W/m2 of this energy is reflected or scattered back into space by clouds, the atmosphere, and high-albedo features on Earth's surface. So, only 235 W/m2 (342 - 107) of energy actually make it into the atmosphere, and shines down upon us giving me women in miniskirts and the ability to grow food (both of which are....awesome)
Furthermore, we know that 67 W/m2 of the incoming energy is absorbed by the atmosphere, and another 168 W/m2 is absorbed by Earth's surface. When energy is absorbed, it raises the temperature of the substances that absorb it (the atmosphere and surface of our planet, in this case); this causes those substances to radiate away that heat in the form of IR radiation. We can all agree that these are not simply my opinions right? For those of who are are unfarmiliar, these are called facts, lets keep going.
About 390 W/m2 of IR energy starts upward from the surface, this difference being caused by longwave radiation needing an atmospheric window that does not have a lot of water vapor or gas molocules containing three or more atoms (i realize this is incomplete, i am atempting to simplify). The more of these conditions present in our atmosphere, the harder it is for longwave radiation to escape. So when we spew into the environment, and what we need to agree on is that adding vapor and GHG's to the environment increases the GW potential... right? Keep your fucking anecdotes to yourself, Using these things called facts we can see that keeping equilibrium becomes more difficult when we insist on changing the atmosphere. So don;t tell me you got two colds last year and only on this year so we are getting warmer, or that your uncle your uncles garden got frosted early thid year so we are geting colder. Or about ICEBERGS, this is an atmospheric issue, give me meaningful data about that and i will listen. Anyone who thinks that chnging the composition of our atmosphere will not result in temp change needs to back to school.
sig loading.......
now, I'm still processing all the data for myself on global warming, and have not made my final decision one way or the other. I am leaning towards the idea that anything we do to prevent/correct global warming *That Does Not Cause More Harm If We Are Wrong* is a good idea. That said, I do have this question:
/. is the pinnacle of human communication or anything, but it seems to me that if you want to have a rational discussion abut the subject, and perhaps attract a few more people to your cause (saving the planet from humanity?) then opening with generalizing insults may not be the way to go.
Why is it, when this topic comes up, so many people that are on the side that says human centric global warming is a fact; tend to use the argument that anyone who does not agree with them is a right-wing gun toting SUV driving mentally crippled slack jawed idiot?
Now, I don't pretend that
I've decided to Diversify my Holdings. I've divided my cash between my left and right pockets, instead of all in one.
I'm not a loon, it really is an envirocommunist worldwide conspiracy to overthrow the illuminati oil-lords. That only seems far fetched to those who uses non-rectal sources for their news. Step back a bit, look at the situation as a whole, and forget about the day to day details (facts at a high enough rate are just noise), then pull out a theory. Your colon can come up with interesting patterns, and facts are unnecessary ingredients for their assemblage.
refactor the law, its bloated, confusing and unmaintainable.
"From the data he posted, it doesn't look like the 2000s, or even any multiyear period between 1980-2010 was exceptionally warm"
The Artic is warming at about 3X the rate of temperate zones, the phenomena is called Polar Amplification, it was predicted by one of James Hansens models in the 80's and has since been confirmed by obsevation.
"it would seem to suggest that a big iceberg calving in Greenland might not be global warming related"
Somewhat tautologically the trend that shows AGW is causing ice loss is composed of billions of individual events, none of which can be said to be caused by AGW. It's like thowing dice that are loaded in such a way that the odds of snake's eyes are 10/36 rather than 1/36. You can never say for sure that a particular occurance of snake's eyes was due to the loading, but you can be certain the dice are loaded.
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
During the Younger Dryas, there were large amounts of extinctions throughout N. America, and forests in Scandinavia were replaced with glaciers.
Yes, there have been periods of abrupt climate change in Earth's history that have happened without human involvement. Regardless of cause, they are invariably followed by a large list of bad things happening, with very few good things.
Not a typewriter
Why is it, when this topic comes up, so many people that are on the side that says human centric global warming is a fact; tend to use the argument that anyone who does not agree with them is a right-wing gun toting SUV driving mentally crippled slack jawed idiot?
Tribalism, mostly. People naturally divide the world into us vs. them on any given subject. While I feel that AGW is the only scientific explanation, most of its supporters are not scientists, much less climate scientists, and many of them jump into fanciful imaginings and impractical plans, doing their cause a great disservice.
Not a typewriter
It appears one side has a lot more rational people than the other; and the other has a lot louder loons. Both sides will doubtlessly agree.
---
Although it is not true that all conservatives are stupid people, it is true that most stupid people are conservative. J S Mill
Tribalism, mostly. People naturally divide the world into us vs. them on any given subject.
Well I am certainly in the anti-tribalism group!!!!!
Qxe4
I really like your straw man attacks on someone's straw man attacks.
Don't disappoint your bird dog. Go to the range.
It's probably true, however unlikely it seems to you, but one of the best proofs doesn't come from animals. Plants don't wander around - Once a tree grows in a spot, it's committed. Some plants in particular drop heavy nuts or seeds that will only get transported as far as animals will move them at the very most, and some spread by runners or similar methods that mean the offspring will always be close to the parent and moving across large distances takes many generations. For one example that's been particularly useful to biologists, evergreens that live on tops of mountains above the deciduous tree line usually stay there unless the climate gets so warm that tree-line moves higher than the mountaintop. Climate change at one rate may let some of these species relocate, but at a faster rate will simply wipe them out locally. In the same way, some plant diseases may spread widely only if the tree-line becomes so low, the mountain peaks are all connected. That's a distinctive, temperature related effect. We can look at plant fossils and make some pretty good estimates of how long it took for prehistoric changes, in particular, there are formulas based on longevity and reproductive frequency that hold if species X stays viable in some area for Y time, the rate of change had to be slower than Z. I't's a pretty good argument if species are now going locally extinct at 10xZ or 50xZ rate, that nothing like that has happened in pre human times, or we wouldn't have living examples of those species. Because some of the currently observed rates can be tens or more times faster than the prehistoric rates, rather than just, say 50% faster, it's considered an unambiguous type of evidence.
To be fair, even this line of reasoning takes a lot of crosschecking. Plenty of legitimate scientific disputes exist over just how big a locale is meaningful, or how many different species should be checked before the results deserve a certain level of confidence, or whether the scars left by a particular plant disease are uniformly distinctive. For some cases, scientists do have to consider other events that may have happened that fast in prehistoric times (Dinos weren't the only thing clobbered by that asteroid 60 million years ago). So, it may be only fair to say, "unless the Cretacious extinctions were really caused by some sort of warming cycle and not a massive shield volcano super-eruption, asteroid impacts, or alien trophy hunters, nothing like this, this fast, has ever happened before." But, within limits such as that, the evidence is mounting.
Who is John Cabal?
Why is it, when this topic comes up, so many people that are on the side that says human centric global warming is a fact; tend to use the argument that anyone who does not agree with them is a right-wing gun toting SUV driving mentally crippled slack jawed idiot?
Because it's patently obvious that humans are the cause of it. It's just an absurd proposition that there is any other significant cause of climate change. Yes, you would have to be some kind a slack-jawed right-wing gun toting idiot, or equivalent, to think otherwise.
You know all this mess in the gulf that people are hysterical about? Imagine 15,000 other deep water oil leaks of the same size spread out across the oceans, and what kind of hell that would be. Because that's the amount of oil we are burning each year. The idea that burning it all instead of letting it leak makes it all but harmless is madness. Less directly harmful that letting it leak, probably, but still plenty bad.
Just being uneducated wouldn't even be enough to explain it. Take a look at yourself for instance. You "haven't made a final decision yet"? Science doesn't make "final decisions". If new facts come up, scientists change the 'decision'; there is no 'final'. The evidence is so overwhelming right now that really the only way to deny it is to un-scientifically hold out for an absolute... well we can't be 100.0% sure so reserve judgment. Mathematics and religion works on absolutes, not science. So it's not even a question of education or intelligence, it's really a question of whether you have to courage to face the facts or not.
I think really the problem is that the scale of human activity is simply too great for many people to comprehend. People that haven't ever left their own town and aren't worldly just don't have the resources or motivation or fortitude to even contemplate it. So I don't hold out much hope for society to change before it's too late. And it's not too late, yet, but we'll need massive infrastructure changes or something drastic like say a solar shield to keep anything resembling our current climate.
Ooh, Watts -- everybody's favorite college-dropout electrical engineer who likes to play climatologist and who pretends to be a certified meteorologist!
What a great link -- is it Lets Cherry Pick Data And Then Pretend That It Overrides Peer-Reviewed Analysis time again already?
"I like your Christ. I do not like your Christians. Your Christians are so unlike your Christ." - Gandhi
If it's about averages, then you have to set the bar for the average. You can say a 30 year average is significant, or a 60 year average, or a 600 year average, or a 6,000 year average.
No, that would be called "making things up". Statistical significance requires statistical evidence. And we have ample evidence that the planet's temperature is dominated on the inter-annual scale by ENSO, and to a lesser extent, by other factors, but is dominated by AGW on the multi-decadal scale.
We have tons of data on ice extent. Most people know that, back to 1979, we have a beautiful record of satellite readings with only small holes. But there's a lot more.
Before that, we have sailing logs and logs from Arctic cities for the arrival and departure of ice. A particularly good source of data is the records from the US and Soviet navies' submarine fleets, which has been made available to researchers. There's direct written records from sailors all the way back to the dark ages, although these progressively become much patchier and are usually only good for localized ice extent.
From coastal records, the data dates back as far. Starting in the late 1800s, it becomes very good, and is near complete starting in the 1950s. Iceland has a good 1,200 year record.
Probably the best long-term record we have is that of sediment cores, and just recently we've started getting an increasingly number of papers on the subject (due to the hostility of the region, only readily have many cores become available). Here's a good review. There are several types of sediment proxies.
The first includes the deposition of ice-rafted debris. Large grains of minerals don't just appear in the middle of the ocean. They're too big to blow and too heavy to float. We observe the process of ice rafted debris being deposited in present day. The debris comes in two types: smaller grains from coastal margins, and larger grains from icebergs. The size, shapes, chemical signatures, and surface characteristics of the grains bear hallmarks of their origins and of the type of ice conditions at the time.
A second source of data in sediment cores is that of microfossils. Different types of plankton have different habitats in which they can live (i.e., some can live under ice, others can't) and known sedimentation and preservation rates. A third, and similar, technique involves the fossils of bottom-dwelling organisms. This may seem odd, as they're not directly affected by the ice -- but they're *hugely* indirectly affected. Very little organic matter, which such organisms eat, is deposited beneath the ice sheet; however, vast quantities are deposited around the edges of the ice, and a normal amount beyond it. Their populations are shown to well correlate with ice cover.
A fourth technique, like the above, involves the amount of organic matter itself deposited. Beyond just quantity, you can look at chemistry -- for example, there are chemical biomarkers for diatoms that live in sea ice.
At the coasts, you have a lot more data, as sea ice has significant affects on the land when it touches. This affects everything from whalebone to large mollusks to driftwood to plant matter and so forth. Even arctic tree records provide significant data, as arctic trees do not survive along coasts perennially lined with ice.
Concerning driftwood: wood cannot pass through ice. Driftwood floats, becomes waterlogged, and sinks in open water. Driftwood entrained in sea ice collects in quantity at the ice margin, and corresondingly sinks in quantity at such locations. Massive quantities of driftwood fossils are available.
Various types of sea mammals closely correspond with the ice margins -- polar bears, various species of seals, walrus, narwhal, beluga, and bowhead. T
"I like your Christ. I do not like your Christians. Your Christians are so unlike your Christ." - Gandhi
Which would be a valid argument if that's what scientists were actually doing. The early 20th century warming is a combination of several factors -- first, a strong shift in the PDO, and then followed by not only a decline in PDO, but a rapid increase in global industrialization. The latter might seem like it would have just the opposite effect, but you have to remember that until the 1960s/1970s, there was very little regulations on power plant emissions. While CO2 causes warming, it has to accumulate for this to happen. Far more rapid is the cooling effects of chemicals like sulfur dioxide, which were emitted en masse until the first world started mandating scrubbers on its power plants. While SOx has a relatively short (compared to CO2) residency, so it's really just a masking of the real climate, its affects are quite powerful.
"I like your Christ. I do not like your Christians. Your Christians are so unlike your Christ." - Gandhi
No, today's warming is faster.
The early 20th century warming is a combination of several factors -- first, a strong shift in the PDO, and then followed by not only a decline in PDO, but a rapid increase in global industrialization. The latter might seem like it would have just the opposite effect, but you have to remember that until the 1960s/1970s, there was very little regulations on power plant emissions. While CO2 causes warming, it has to accumulate for this to happen. Far more rapid is the cooling effects of chemicals like sulfur dioxide, which were emitted en masse until the first world started mandating scrubbers on its power plants. While SOx has a relatively short (compared to CO2) residency, so it's really just a masking of the real climate, its affects are quite powerful.
"I like your Christ. I do not like your Christians. Your Christians are so unlike your Christ." - Gandhi
You, sir, have astounding powers of estimation.
;-)
A more likely explanation would be that I did the same math. But thanks for double checking my work
This issue is a bit more complicated than you think.
The "data quoted at the end"? What end? It's a looping image (really annoying, by the way). And it's still cherry-picking. Individual ice cores for a single location do not a planetwide temperature average represent; that's what peer-reviewed papers on reconstructions using *all* available data are for.
"I like your Christ. I do not like your Christians. Your Christians are so unlike your Christ." - Gandhi
Why do people always talk about whether the earth will survive, or whether it has survived something like this before? Who cares about this rock. Global warming won't kill the earth; it'll be here long after humanity has gone. It doesn't matter whether earth has gone through this before, because we're not trying to save the earth. We're trying to save us.
What matters is whether the current population of humans can survive a sudden, drastic temperature increase, not whether the earth can.