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Arctic Sea Ice Rallies a Bit
radioweather writes "Like the recent stock market rebound, Arctic sea ice is making a big rally over the record low set last year. According to the Alaskan
IARC-JAXA website, satellite data which shows sea
ice extent as of 10/14/08 was 7,064,219 square kilometers, when compared
to a year ago 10/14/08 it was 5,487,656 square kilometers. The one-day gain between 10/13/08 and 10/14/08 of 3.8% is also
quite impressive. On May 5th, The National Snow and Ice Data Center suggested
the possibility of an ice-free north pole
in 2008, but so far, this year has been a banner year for sea ice recovery."
Uhh....what? http://moneycentral.msn.com/detail/stock_quote?Symbol=$INDU
The greatest revenge in life is massive success.
News reports have indicated that the earth's weather climate has been constantly shifting over millions of years.
Seriously, I wish people would stop getting so shocked about this. I remember reading in school about things like Ice ages and constaly changing climates, and I'm not that old. I beleive man's impact on the enviroment, while measurable, is severly overblown.
According to the study's website, the extent of the ice coverage is an estimate "calculated by certain algorithm."
It would be premature to suggest this as a panacea without knowing the statistics behind this estimate. Without this, we don't know if 3.8% is even statistically significant? They don't even offer a margin of error.
Even the "Data Download" offers only the bottom line estimate at a given point in time. What is the formula that feeds into that?
...its called *Winter*
Of course not. I'll explain.
Earth heats up: Global Warming
Earth cools down: Global Warming getting worse.
Violence is like duct tape. If it doesn't solve the problem, you didn't use enough.
2008
is the coldest year of the 21st century and output from the sun is declining.
Maybe Al Gore and his carbon cult followers were...wrong.
I hear soybeans and arctic ice are really hot right now.
The Mauder Sunspot Minimum in the 17th century has been arguably tied to the Little Ice Age, a cool period. The new 11-year sunspot cycle #24 has been very slow to start as predicted in late 2007. There have been as few as five sunspots in all of 2008. During the active part of the cycle there are up to 150 at a time. The sun is about 0.1% weaker during the cycle minimum. Perhaps this correlates with cooler weather. There are better tools now for tying solar weather with earth climate and maybe someone will find a causal tie.
No, and they're being *deliberately* misleading. Arctic sea ice this year hit the second lowest level in recorded history. Last year was the lowest.
Arctic sea ice extent during the 2008 melt season dropped to the second-lowest level since satellite measurements began in 1979, reaching the lowest point in its annual cycle of melt and growth on September 14, 2008. Average sea ice extent over the month of September, a standard measure in the scientific study of Arctic sea ice, was 4.67 million square kilometers (1.80 million square miles) (Figure 1). The record monthly low, set in 2007, was 4.28 million square kilometers (1.65 million square miles); the now-third-lowest monthly value, set in 2005, was 5.57 million square kilometers (2.15 million square miles)./I.
To report values now, from *October*, during the refreeze is just bloody ridiculous. Yes, different years melt and refreeze at different times; there's a lot of spring and fall fluctuation. What matters are the maximum and minimum extents.
FYI, arctic sea ice normally low in years after El Nino winters and high in years after La Nina winters. Winter of 2006-2007 was in El Nino conditions, leading to the record 2007 melt. But winter of 2007-2008 was in a strong La Nina. The fact that we got the second lowest ice extends on record despite this is incredibly disturbing.
If I ever become wealthy and mad, I'll leave Companion Cubes on desert islands for shipwreck survivors.
I'm sure President Palin will fight back the ice fantastically efficiently, for the good of the economy. You betcha!
http://rocknerd.co.uk
It's important to keep in mind that this isn't a measure of how much ice there is in the arctic.
The figures they are reporting are sea ice coverage estimates, and typically work as follows: the arctic is broken up into a grid, and for each area of the grid which does not fall on land they ask the question "is >15% of the surface covered with ice?"
If the answer is yes, it's counted as "ice;" if not, not.
There are several ways this can give results you wouldn't expect:
--MarkusQ
If the ice it's really coming back... I'd like to know why :)
Ia! Ia! Cthulhu F'thagn!
No, this report only discusses extent. There are other people who report ice volume, which is more difficult to estimate. I don't know what the current volume estimate is.
Long live? I would rather compare them to rabbits - 5000 in 1950, 20000 - 25000 now. But the little polar bear who is apparently in danger looks sooo cute on a poster... Environmentalists are all about donations after all. And saving polar bears is so easy -- you can always show results.
Long live my carma...
So the volcanos on the Lomonosov and Gakkel ridges shut down. Less steam heating of the bottom of the Arctic Ocean, less ice melts at the top of the ocean.
And this boggles peoples minds because....?
Michel Jarraud, who is a big fan of global warming, of the World Meteorological Organization reluctantly admitted that global temperatures have not risen since 1998, according to a BBC article.
That's a pretty misleading representation of what he said.
Global snowfall is at record levels
I haven't looked at snowfall records, but global precipitation is expected to increase in a warming world.
and there are fewer, not more, hurricanes.
AFAIK, there are more hurricanes. Some research suggests that there will be yet more in the future, some research suggests there will be fewer; some suggests they will get stronger even if fewer. Hurricanes are a legitimate area of deep uncertainty in climate science; it's not clear how their behavior should change.
"But what your so sure of you shouldn't be."
Good advise, but your own risk assesment that you are 'so sure about' doesn't have any probability caveates at all?
The GP did have one such caveate (ie: 'likely'), the best science available says 'very likely'. But maybe I have misunderstood, maybe you are talking about the GP's implicit assumption that humans are causing the climate to change, if that's the case then the science says 'certain'.
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
You're driving in complete darkness and someone tells you there might be a cliff nearby. You're told to err on the side of caution. What do you do?
Turn on the headlights. For fuck's sake do you WANT to get eaten by a grue?!
that while we thought we had nature on the ropes, nature rebounds and shows us that nature really is a mother.
"Suppose you were an idiot...and suppose you were a member of Congress...but I repeat myself." Mark Twain
Correct, but bear in mind that this isn't a measure of sea ice coverage either; it's a doubly aggregated value that must be taken with a dram of salt water. While it is true that the percentage of sea surface covered with ice is strongly correlated with local albedo, the percentage of sea surface parcels which are covered with more than a certain threshold percentage of ice is much less strongly correlated, especially when that percentage is far from the median. IIRC correctly, using the median value as the threshold and weighing it as the mode gives the best fit.
To but this more concretely, a set of parcels with ice coverage of (0.16,0.16,0.16,0.16,0.16) would have an albedo of 0.84*sea + 0.16*ice, but show up in this survey as 100% ice. A set with (0.14,0.14,0.99,0.14,0.14) would have an actual albedo almost twice as high (0.69*sea + 0.31*ice) but show up in this survey as only 20% ice.
--MarkusQ
It's not misleading; summer minimum ice extent and annual ice extent are two different quantities, both of which are interesting and climatically relevant.
The polar bear is often regarded as a marine mammal because it spends many months of the year at sea.[24] Its preferred habitat is the annual sea ice covering the waters over the continental shelf and the Arctic inter-island archipelagos. These areas, known as the "Arctic ring of life", have relatively high biological productivity in comparison to the deep waters of the high Arctic.[20][25] The polar bear tends to frequent areas where sea ice meets water, such as polynyas and leads (temporary stretches of open water in Arctic ice), to hunt the seals that make up most of its diet.[26] Polar bears are therefore found primarily along the perimeter of the polar ice pack, rather than in the Polar Basin close to the North Pole where the density of seals is low.
...
Annual ice contains areas of water that appear and disappear throughout the year as the weather changes. Seals migrate in response to these changes, and polar bears must follow their prey.
The 'original' poster is right. Polar bears do Not go that far north.
No, it was a heuristic I picked up from a statistician I worked with years ago, and I'm not even certain I've stated it correctly.
The basic idea is a generalization of the rounding rule. If you have a bunch of values evenly distributed between 0.0 and 1.0 you can approximate their sum by counting how many are >= 5.0 and multiplying by 10. So I see already that I got it wrong. The real rule would be count everything over the median as twice the mean, and the mode doesn't figure into it. Unless I'm still remembering incorrectly.
That should teach me to post late at night. My advice would be, if you need to know the actual rule, consult a statistician or a good statistics book, not random programmers on slashdot.
--MarkusQ
P.S. My failure to remember the best of many bad ways to doubly aggregate data actually underscores my main point, which is that its a very tricky thing to get right, and even in the best of circumstances you have to be careful drawing conclusions from the results. * And if
Ambitwistor has posted over 30 replies in this thread, all of which were well written and well thought out.
Since the majority were done during working hours, and since most anyone would be fired for screwing around on the internet during working hours, it is clear that Ambitwistor is a paid hack working for the Global Warming Industry.
As such, his posts are nothing more than propaganda, his science is crap, and he should be prosecuted for crimes against humanity.
When Fascism comes to America, it will call itself Anti-Fascism, and tell you to give up your guns.
I mistyped the closing tag. That wasn't intentional.
If I ever become wealthy and mad, I'll leave Companion Cubes on desert islands for shipwreck survivors.