I'm interested in the facts and always have been. So no I have not changed my position. I find exaggeration and dramatics deplorable when used by either side of the argument. Also I find mindless insults a waste of keyboard time.

A task I frequently perform at work is to look at data that is 2 standard deviations from the mean. This is usually where I find invalid data. When I look at a chart of ice extent and see recently entire years are outside of this range, I know something really strange is happening. I know that data is correct because it comes from images that are publicly available. What we have is a statistically significant result that has been repeated again in 2009. It is hard to be overly dramatic when the possibility exists for this to cause a mass extinction event.

I sometimes don't care to mitigate such consequences. I think the competition for resources will lead to evolutionary progress for the species if extinction does not occur.


http://nsidc.org/images/arcticseaicenews/20091103_Figure2.png

It wasn't intended to be an insult.

Sorry that shot wasn't directed at you.

What happened to 2006?
While statistical analysis is a great way to measure the quality of a production process I for one am not sure it can be applied to a complex process like the weather. Two standard deviations define good? Says Who ? Perhaps mother Nature thinks four standard deviations are just fine. And in any process you have to decide what defines good. Perhaps we are measuring the wrong thing or in the wrong way. Like our three intrepid researchers that set out for the pole last spring to measure the ice thickness. Their results were skewed from the start by their choice of start off point and the limits of human ability to walk in -40C weather. There sample size is too small and wasn't worth the frost bite.

Thanks for the informative article you presented above, vt. That this info does not seem to trouble you leaves me wondering what kind of data exactly you would find to be worrisome? Could you imagine any such? Your argumentation so far would seem to imply that any data, no matter how dire or outside the norm, may just be normal if we just redefine normal. This seems a pretty convenient position if you are determined no to see a crisis no matter what.

Who said I wasn't troubled? Just because I don't expect the ice cap to become detached from Greenland and float down the Fram straight next summer doesn't mean that I don't take the climate seriously. But a crisis? no if you want to talk about crisis start with the human population problem and the fish stocks in the ocean, then move on to peak oil which is made worse by the population problem and much of the worlds oil supply in the hands of religious fanatics. Compared to that watching the ice at the pole wax and wane is relaxing and watching people hyperventilate about it quite amusing.

I tend to agree that Peak Oil and other environmental problems trump climate change in terms of immediacy, and may even mitigate in some ways. The potential impact of climate change on the earth's ecosystem is however IMO greater.

Population is the biggest cause and PO could address it in some ways.

I believe we need to concentrate on PO because the action needed to address Climate Change is beyond our powers.

My thoughts are that over population is the core problem, every thing else is at least one tier down.

Off the top of my head the second tier contains: Peak Oil, water shortages, disease/infection, food supply destruction, global warming, +???

Then in the third tier would be: financial distress, civil discord, political/religious radicalization, etc.

I believe that the scenarios are too complex to model and predict. Almost anything can happen.

What I don't know how to classify is the complexity of our social/financial/distribution structures. It strikes me, right or wrong, that the whole mess has gotten just too damn complex and must ultimately fall . Fast or slow? Don't know. At least slow, maybe fast.

If GW kicks in fast enough, not due to rising water level but desertification and changing water patterns, it could cause a relatively short term crisis/war.

Just some thoughts.

2006 was left off the graph but it fell outside of the 95% confidence interval for most of the year. So we have 2005-2009 all outside of 2 SD. So a quick check on the statistical probability, 0.05^5 (probability that five years fall outside of interval) = less than 0.00004% chance of that being random.

We can also look at the images and see greater melt over the past few years than the previous 21 years.

My mission isn't to convince anyone, just want to read observations and share observations on one of the more noticeable effects that our species is having on the planet.

Interesting you quote the image here;

http://www.arctic.noaa.gov/reportcard/f ... 09fig3.jpg

from the page

but not the graphs below that image;

http://www.arctic.noaa.gov/reportcard/f ... 09fig4.jpg

which both show the multi year ice in 2008 is thinner then the multi year ice in 2004, 2005, 2006, 2007, which means it is thinner, and less total ice must be present.

From around 3.35 meters average thickness to 2.8 meters average thickness (based on the graph)

and of course this quote about sums it up;



a decrease of 1.7 m in thickness.

In other words almost half as much ice in thickness then as recent as 1980.

PS, if you compare the 2007 multi-year ice area to the 2009 multi-year ice total area it is obviously much less.

and since all the multi year ice directly east (in the Mar 2009) of the Greenland land mass disappeared this year during the melting season,

that is gone also, add that loss and the remaining is much less this year around.

arctic sea ice below 2007

antarctica sea ice at the long term average

[quote="kiwichick"]arctic sea ice below 2007

The IJIS graph shows it about even or within the margin of error. I wonder if it tracks 2006 if that will be an indication of another 2007?
http://www.ijis.iarc.uaf.edu/en/home/seaice_extent.htm

Antarctica has been following below the 2007 line. 2006 was the lowest extent in Antarctica, but 2009 was second lowest with 2007 a close third.

http://iup.physik.uni-bremen.de:8084/amsr/ice_ext_s.png

How do you make the charts smaller so you can post them?

2009 punches through 2007 track.

chart