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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.
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
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!
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.
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I really like your straw man attacks on someone's straw man attacks.
Don't disappoint your bird dog. Go to the range.
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.
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
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.