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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."
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?
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.
Lets ask this question:
Do you want to walk on ice that froze an hour ago? or ice that's been solidly frozen for decades?
The ice 'recovery' is a misnomer, even if it covers the entire arctic at peak winter, it won't be very thick compared with persistent perennial ice cover that has existed and built up thickness for hundreds/thousands of years.
Replacing 'steel' with 'balsa wood' doesn't mean the structure can hold up the same weight. i.e. polar bears.
People in cars cause accidents....accidents in cars cause people
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.
Solar output and atmospheric heat retention are two completely independent variables.
The fact that one is rising, while the other is falling is merely a fortunately coincidence.
My own personal view is that there's a heck of a lot that we don't know about the mechanics of the atmosphere. Until we figure everything else out, though, it's probably a good idea to err on the side of caution.
-- If you try to fail and succeed, which have you done? - Uli's moose
I think it's cute how people like you think that the IPCC is either unaware of or deliberately ignoring papers like this ;)
Seriously -- read the report some time. It'll be educational for you. There's something like 50 papers referenced for just sunspots alone. If it A) has to do with global warming, even tangentially, and B) was published in a peer-reviewed journal in the past 10-20 years, odds are it's in there.
Science does not work in a manner of "this one paper says one thing about one aspect, so it must be God's honest truth!". The amount of research out there is pretty staggering. It is... let's just say "unfortunate" that the popular press has a habit of picking up one work or another and sensationalizing them.
If I ever become wealthy and mad, I'll leave Companion Cubes on desert islands for shipwreck survivors.
Once again, this is why people who don't know anything about a topic shouldn't comment on it.
Earth's oceans, especially the Pacific, are truly massive heat reservoirs, and changing how they interact with the atmosphere can strongly affect the atmosphere's temperature in the *short term*. In the long term, the planet is still dominated by its radiation balance, of course.
The linked article was describing, quite accurately, how the early part of this year was in La Nina conditions. El Nino is caused by the weakening or reversal of the Walker circulation (an atmospheric flow around the Equator). The Walker circulation helps encourage the upwelling of cold waters in the eastern Pacific, so El Nino conditions prevent more of this cool water from reaching the surface. As a net change, the equatorial Pacific ends up much warmer on the surface, raising atmospheric temperatures. In La Nina conditions, the situation is reversed; a stronger Walker circulation encourages more upwelling, and thus colder surface (and hence atmospheric) temperatures.
This has *absolutely nothing* to do with the planet's long-term temperature, which even a six year old looking at a graph could recognize through the year-to-year noise.
Now, if you *really* want a breakdown of how it ranked (records since 1880), here you go (remember that the first half of this year was in strong La Nina conditions!):
January: 31st warmest
February: 15th warmest
March: Warmest for land on record, 13th warmest for ocean
April: 13th warmest
May: 8th warmest
June: 8th warmest
July: Tied for 5th warmest
August: 10th warmest
September: Tied for 9th warmest
Spring: 7th warmest
Summer: 9th warmest
January to July: 9th warmest
If I ever become wealthy and mad, I'll leave Companion Cubes on desert islands for shipwreck survivors.
Ironic isn't it that some people who so easily dismiss decades of research by thousands of scientists will so willingly glom onto one report that might ever so slightly support their lifestyle choice?
Notmysig
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
Seriously, I wish people would stop getting so shocked about this.
Climatologists are not unaware that the climate has changed in the past. The issue is that climate is currently changing faster than it would have without human input, and that larger and faster changes are likely if we continue to increase our input to the climate system.
If I'm told to err on the side of caution, do you know what I would do? Nothing!
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? Speed up? I think not. You stop, or at least slow down.
Right now CO2 levels are already higher than they've been in at least a million years, and we're increasing them at an accelerating pace. Basic physics as well as our observations of present and past climate suggest that this will lead to warming, possibly by a dangerous amount.
Continuing to add CO2 at an accelerating pace may be "doing nothing different", but it is not "doing nothing". It is doing a very significant Something.
We don't know everything about the climate, but we know that reducing CO2 back to pre-industrial levels is unlikely to do anything worse than keep us at the present climate (and even then we are likely to still warm a little due to heat already stored in the ocean). By contrast, there are a lot of climate risks associated with staying on our current emissions trajectory.
My own personal view is that there's a heck of a lot that we don't know about the mechanics of the atmosphere. Until we figure everything else out, though, it's probably a good idea to err on the side of caution.
And which side is caution on, exactly? Spending money (that could be used for other things) to reduce CO2 emissions "just in case", or not spending money tinkering with CO2 because if global warming turns out not to be anthropogenic, we could bring on the next (little?) ice age?
(I happen to think the effects of a minor global temperature increase are a lot less serious than the effects of another ice age, but that my just be my Canadian upbringing talking.)
-- Alastair
You are conceding, then, that the reflectivity of the cloud cover can vary from year to year. That puts you ahead of many global warming advocates.
No, it's a well known fact.
Isn't it also possible that warmer surface temperatures (which you must admit would be expected with global warming) would lead to increased evaporation, increased atmospheric moisture, and increased cloud cover, thereby increasing reflectivity and providing a global temperature feedback control mechanism?
Yes. There are two major cloud feedbacks, one for cloud albedo cooling as you describe, and one for cloud greenhouse warming.
Yet, current models either don't account for that or simply assume that reflectivity is constant.
That's wrong; dynamic cloud feedbacks are in all modern GCMs.
Nevertheless, the CO2 theory of global warming must result in more heat present in the oceans every year.
No, it doesn't, for reasons I just stated.
Of course, that's not what is observed, which completely undermines the entire simplistic theory of co2-based global warming,
As I just said, (1) cloud modulation alters your claim of "monotonic heat increase", and (2) ocean heat observations are not very accurate.
but its adherents wave that away as a minor point,
That's because there isn't anything yet statistically inconsistent with model predictions.
just as they ignore variations in heat originating in the planetary core
They're ignored because they've been measured and are utterly negligible, on the order of a hundredth of a degree.
and variations in solar output.
Those aren't ignored either; there is a large literature of it, and is in fact one of the pieces of evidence supporting CO2-induced warming. Solar output trends are inconsistent with the warming which has been observed.