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NASA Satellite Measurements Show Unprecedented Greenland Ice Sheet Melt
NASA reports that measurements taken from orbiting satellites indicate the Greenland ice sheet underwent melting over a larger area than they've seen in 30 years of observations. On July 8, the satellites found evidence that about 40% of the ice sheet's surface had melted. Observations just four days later showed 97% of the surface had melted.
"This extreme melt event coincided with an unusually strong ridge of warm air, or a heat dome, over Greenland. The ridge was one of a series that has dominated Greenland's weather since the end of May. 'Each successive ridge has been stronger than the previous one,' said Mote. This latest heat dome started to move over Greenland on July 8, and then parked itself over the ice sheet about three days later. By July 16, it had begun to dissipate. Even the area around Summit Station in central Greenland, which at 2 miles above sea level is near the highest point of the ice sheet, showed signs of melting. Such pronounced melting at Summit and across the ice sheet has not occurred since 1889, according to ice cores analyzed by Kaitlin Keegan at Dartmouth College in Hanover, N.H. A National Oceanic and Atmospheric Administration weather station at Summit confirmed air temperatures hovered above or within a degree of freezing for several hours July 11-12."
Photos also surfaced last week showing the Petermann Glacier in Greenland 'calving' — some very large chunks of it broke off and started to drift away.
"Ice cores from Summit show that melting events of this type occur about once every 150 years on average. With the last one happening in 1889, this event is right on time," says Lora Koenig, a Goddard glaciologist and a member of the research team analyzing the satellite data. "But if we continue to observe melting events like this in upcoming years, it will be worrisome."
"First they came for the slanderers and i said nothing."
Everyone is really good at rationalizing specific data points like "it's part of a 150 year trend". The problem is there's world wide evidence and not just glacier melts. There's a measurable trend going back to the industrial revolution when the CO2 release started. It accelerated in the 80s as growth in third world countries kicked in. It's everything from glacier melting to weird weather and from sea level rise to a severe drought in the US to the worst one in Australia in several thousand years. What I keep hearing is every time a piece of evidence shows up is "I can explain that". At what point do we accept that all the "I can explain thats" add up to we've got a problem? Long term what we are staring at isn't a hot planet but one that overreacts to a spike in CO2 causing a worse ice age than the last one. Rationalizing is a little like sticking your head in the sand. Each rationalization is another inch. Eventually your head hits China and the planet is still warming whether you like it or not.
...and caused the Little Ice Age in Europe.
Not just in Europe. In 1776, Alexander Hamilton was able to drag the guns of Fort Ticonderoga across the frozen Hudson River to New York. By 1830, the ice on the Hudson was too thin for that, and by 1850 or so, it had completely stopped freezing over.
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>"Troll"??? This is EXACTLY the same argument used by AGW proponents, when they are confronted with the fact that Country X had a colder-than-normal winter last year: "That's not climate, it's weather."
No it's not, the two arguments aren't even superficially similar though one is designed to try and look as if it is the other one - it's a bad make-up job that you fell for hook-line-and-sinker.
AGW proponents (in particular scientists) look at global averages, and the expected outcomes of that. They expect weather in some areas to change because of average warming in ways that may not be alike- including that global warming can CAUSE some places to have unusually cold weather.
Let me try and make this simple. If you have a clay fire oven, it's well known that there are "cold spots" in the oven where the movement of warm air actually creates convection holes that are significantly colder than the rest of the oven (any Pizza chef will have seen that for himself), in some cases those spots will actually be colder than the ambient room temperature (since the convection actually sucks the hot air from them) by a small degree (this is an extreme case for a pizza oven but on the scale of a planet it's not even slightly extreme but expected).
Now before you light the fire - the temperature is relatively uniform in the oven, no hot or cold spots. But as the fire warms up the cold spots form. The increase in the average temperature of the air in the oven actually CAUSES some parts to drop in temperature.
Yes, this is a terrible analogy and the real stuff we're talking about is massively more complex but the point of the analogy is merely this: most "colder than average" reports actually PROVES an increase in average warming. They are evidence that AGW is happening, not that it isn't.
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Well in the UK I think we're probably prepared. This last 7 years or so we've seen everything from massive increases in rain through to winters that have been about 20C below historical averages.
In each case it's been because the jetstream has moved out of it's normal position. In March we had drought conditions across most of the country, since then we've had record historical rainfall ever recorded for the month of July and so forth. In 2010 we had a January/February that was so bad we hadn't seen one like it for about 40 years, by November that year it happened again, so from once in 40 years, to twice in a year. Last winter was unusually mild, we barely even went below 0C which was in stark contrast to the -20C we'd seen the two winters previous. For reference, normal winters would see lows of -6C to -8C where I live.
Perhaps it's a natural cycle, perhaps it's because of man's actions, but either way the jetstream running over the UK has been acting quite differently to what we're used to since at least 2005. It could well be that effects on the gulfstream are already causing what you suggest.
On the upside, whilst the weather we've had with a lack of jetstream in it's normal position is not pleasant, it's certainly not going to be the end of civilisation at least - we've managed to cope the last few years, but it seems it means we don't get proper summers anymore.