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Post by graywolf on Apr 6, 2015 9:25:17 GMT
Just so I'm clear here, after the 07' record crash we saw two years of 'rebound' and then what came next? So we have had two years of rebound post the 2012 crash so what comes next?
EDIT: Took a look at Nevens and saw this;
This short note is about Arctic volume where I was so irritated at a claim on some "geek" blog that it has "stabilized and even recovered slightly" since 2006 that I sat down and typed in the Hamilton numbers.
I do hope this admittedly very small contribution (such as it is) from me is useful (a) so people can copy and paste into Comments on websites that do not allow images and (b)I did compute and include decadal averages.
Caution: it is NOT true that the Arctic has "stabilized" (let alone improved) since 2006. It's important to remember that volume of ice depends on both its area and its thickness, and thickness has a long term decreasing trend.
Here are the hard numbers for Volume, showing more than HALF of ice volume has been lost (Sept. minimum annual ice volume for each year) since the "stabilization" of 2006:
Minimum Arctic sea ice volume, in thousands of km^3 (cubic kilometers) From Larry Hamilton with PIOMAS data:
1979: 16.9
1980: 16.1 1981: 12.6 1982: 13.4 1983: 15.1 1984: 14.5 1985: 14.5 1986: 15.9 1987: 15.2 1988: 14.9 1989: 14.6
1990: 13.7 1991: 13.5 1992: 14.9 1993: 12.2 1994: 13.6 1995: 11.2 1996: 13.7 1997: 13.2 1998: 11.5 1999: 10.9
2000: 11.0 2001: 12.2 2002: 10.8 2003: 10.2 2004: 9.9 2005: 9.2 2006: 9.0 2007: 6.5 2008: 7.1 2009: 6.8 2010: 4.6 2011: 4.3 2012: 3.7 2013: 5.4
1980s average: 14.68 1990s average: 12.84 2000s average: 9.27 2006 level: 9.0
2010-2014 average: is (4.6+4.3+3.7+5.4+6.8)/5 = 4.96
This 4.96 (2010-2014 5-YEAR AVG.) average is:
*** A 66% decrease from the 1980s average
*** A 61% decrease from the 1990s average
*** A 47% decrease from the 2000s average
** And compared to 2006 when things supposedly "stabilized"?
A 45% loss comparing the last five years' volume with that of 2006.
For more background, see Neven Acropolis' blog on Typepad, and also the excellent skepticalscience website for more science, and science rebuttals of common myths.
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Post by douglavers on Apr 6, 2015 10:31:03 GMT
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Post by acidohm on Apr 6, 2015 11:18:40 GMT
Was the ice stable at 16.9 before 1979?
There's been a spider in my conservatory since December, now the sun is out and he's noticed a steady increase in temperature and is worried about the future.....
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Post by sigurdur on Apr 6, 2015 11:53:43 GMT
Just so I'm clear here, after the 07' record crash we saw two years of 'rebound' and then what came next? So we have had two years of rebound post the 2012 crash so what comes next? EDIT: Took a look at Nevens and saw this; This short note is about Arctic volume where I was so irritated at a claim on some "geek" blog that it has "stabilized and even recovered slightly" since 2006 that I sat down and typed in the Hamilton numbers. I do hope this admittedly very small contribution (such as it is) from me is useful (a) so people can copy and paste into Comments on websites that do not allow images and (b)I did compute and include decadal averages. Caution: it is NOT true that the Arctic has "stabilized" (let alone improved) since 2006. It's important to remember that volume of ice depends on both its area and its thickness, and thickness has a long term decreasing trend. Here are the hard numbers for Volume, showing more than HALF of ice volume has been lost (Sept. minimum annual ice volume for each year) since the "stabilization" of 2006: Minimum Arctic sea ice volume, in thousands of km^3 (cubic kilometers) From Larry Hamilton with PIOMAS data: 1979: 16.9 1980: 16.1 1981: 12.6 1982: 13.4 1983: 15.1 1984: 14.5 1985: 14.5 1986: 15.9 1987: 15.2 1988: 14.9 1989: 14.6 1990: 13.7 1991: 13.5 1992: 14.9 1993: 12.2 1994: 13.6 1995: 11.2 1996: 13.7 1997: 13.2 1998: 11.5 1999: 10.9 2000: 11.0 2001: 12.2 2002: 10.8 2003: 10.2 2004: 9.9 2005: 9.2 2006: 9.0 2007: 6.5 2008: 7.1 2009: 6.8 2010: 4.6 2011: 4.3 2012: 3.7 2013: 5.4 1980s average: 14.68 1990s average: 12.84 2000s average: 9.27 2006 level: 9.0 2010-2014 average: is (4.6+4.3+3.7+5.4+6.8)/5 = 4.96 This 4.96 (2010-2014 5-YEAR AVG.) average is: *** A 66% decrease from the 1980s average *** A 61% decrease from the 1990s average *** A 47% decrease from the 2000s average ** And compared to 2006 when things supposedly "stabilized"? A 45% loss comparing the last five years' volume with that of 2006. For more background, see Neven Acropolis' blog on Typepad, and also the excellent skepticalscience website for more science, and science rebuttals of common myths. Graywolf: Can you imagine the hysteria that would have developed during the Holocene Climate Optimum if they had today's tech?
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Post by flearider on Apr 6, 2015 15:05:17 GMT
only 26 more yrs till it's back at 16 then .... (sarc)
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Post by graywolf on Apr 6, 2015 18:20:27 GMT
Just so I'm clear here, after the 07' record crash we saw two years of 'rebound' and then what came next? So we have had two years of rebound post the 2012 crash so what comes next? EDIT: Took a look at Nevens and saw this; This short note is about Arctic volume where I was so irritated at a claim on some "geek" blog that it has "stabilized and even recovered slightly" since 2006 that I sat down and typed in the Hamilton numbers. I do hope this admittedly very small contribution (such as it is) from me is useful (a) so people can copy and paste into Comments on websites that do not allow images and (b)I did compute and include decadal averages. Caution: it is NOT true that the Arctic has "stabilized" (let alone improved) since 2006. It's important to remember that volume of ice depends on both its area and its thickness, and thickness has a long term decreasing trend. Here are the hard numbers for Volume, showing more than HALF of ice volume has been lost (Sept. minimum annual ice volume for each year) since the "stabilization" of 2006: Minimum Arctic sea ice volume, in thousands of km^3 (cubic kilometers) From Larry Hamilton with PIOMAS data: 1979: 16.9 1980: 16.1 1981: 12.6 1982: 13.4 1983: 15.1 1984: 14.5 1985: 14.5 1986: 15.9 1987: 15.2 1988: 14.9 1989: 14.6 1990: 13.7 1991: 13.5 1992: 14.9 1993: 12.2 1994: 13.6 1995: 11.2 1996: 13.7 1997: 13.2 1998: 11.5 1999: 10.9 2000: 11.0 2001: 12.2 2002: 10.8 2003: 10.2 2004: 9.9 2005: 9.2 2006: 9.0 2007: 6.5 2008: 7.1 2009: 6.8 2010: 4.6 2011: 4.3 2012: 3.7 2013: 5.4 1980s average: 14.68 1990s average: 12.84 2000s average: 9.27 2006 level: 9.0 2010-2014 average: is (4.6+4.3+3.7+5.4+6.8)/5 = 4.96 This 4.96 (2010-2014 5-YEAR AVG.) average is: *** A 66% decrease from the 1980s average *** A 61% decrease from the 1990s average *** A 47% decrease from the 2000s average ** And compared to 2006 when things supposedly "stabilized"? A 45% loss comparing the last five years' volume with that of 2006. For more background, see Neven Acropolis' blog on Typepad, and also the excellent skepticalscience website for more science, and science rebuttals of common myths. Graywolf: Can you imagine the hysteria that would have developed during the Holocene Climate Optimum if they had today's tech? But Siggy how many thousand years ago was the current 'optimum'? When I look at the plots it appears we are well past the Orbital forcings that brought us the Bronze age max?
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Post by sigurdur on Apr 6, 2015 19:15:11 GMT
Graywolf: Not really, in regards to orbital forcings. This is the part that gets interesting.
The Eemian, last interglacial, had a really fast warm up, had temps 5.0C higher than present, yet was shorter in duration that the Holocene.
MIS-11, which I personally find fascinating, had a temperature pattern very similar to the present temperature pattern. The long slow melt, verses the Eemian fast and furious melt. You do realize that the Western Peninsula of Antarctica melted during the Eemian, was well as over 95% of the Greenland Ice mass?
Because of the Eemian, we lost valuable ice proxy data to indicate whether Greenland melt is the "norm" during an interglacial of this duration. Same applies to the WP of Antarctica.
We DO know that there were abrupt shifts in climate DURING the Eemian from Antarctic Ice Cores. But the actual extent is also hard to figure out because of WHERE Antarctica IS. Hints... but no cigars lit.
There is now a more concerted effort to explore, via shell proxy data what has actually happened further back. While orbital forcings have to play a part, the part does not seem to be nearly as important as some would like to believe. The Milankovitch theory has many holes in it, which I hope you know.
What I find interesting is ole Joe Bastardi looks at the meteorlogical past to form opinions on the future weather. Real climate scientists are looking at the actual Climalogical past to look at hints of future potential climate. The idea that we know for certain what the level of CO2 was with a resolution of a decade or two in the past is a new found item, which is not provable with current knowledge. We can detect CO2 on a 1,000 year level, give or take several 1,000 years. But we sure as heck do not know what the level of CO2 or a lot of other gases was with a resolution of a few years.
We know from the Eemian that there were bursts of sea level rise. Harder to tell with interglaicals that are older.
As I have stated, I in no way find it surprising that sea levels are rising, that the ice is melting presently. IF that wasn't happening....I would be really worried for my childrens and grandkids future, in regards to climate. At present I am not worried at all about their climate future. I AM worried about their economic future.
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Post by sigurdur on Apr 17, 2015 2:14:05 GMT
www.washingtonpost.com/news/energy-environment/wp/2015/04/16/the-arctic-is-unraveling-due-to-global-warming-and-the-consequences-will-be-global/We often hear that climate change is radically reshaping the Arctic, a place many of us have never visited. As a result, it can be pretty hard to feel directly affected by what’s happening up in a distant land of polar bears, ice floes and something odd called permafrost. A new booklet from the National Academy of Sciences’ National Research Council wants to change that. Synthesizing much past academy work on the Arctic region, the booklet– being released just before the United States assumes the chairmanship of the eight-nation Arctic Council later this month — blazons this message: “What Happens in the Arctic Doesn’t Stay in the Arctic.”
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Post by nautonnier on Apr 17, 2015 13:17:41 GMT
Was the ice stable at 16.9 before 1979? There's been a spider in my conservatory since December, now the sun is out and he's noticed a steady increase in temperature and is worried about the future..... Well the answer to your question is no, the date 1979 was cherry picked as the highest measure there are satellite metrics back further and of course observations back over a century that show that the amount of Arctic ice follows a cyclical pattern. But this would not suit the meme of we are all going to die if the ice reduces. The world managed extremely well without any arctic ice in the past, we are in the ice-age earth at the moment in an interglacial. In the last 6 hours here the tide has risen about a meter, does that mean that in a day's time it will have risen 4 meters and that after a week it will have risen 28 meters? This is the straight line projections and level of stupidity we are being shown repeatedly. Linear projections are foolish on chaotic or cyclical data and that is what we see all the time from the gullibles.
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Post by acidohm on Apr 17, 2015 13:42:43 GMT
Yeah....I kinda knew that....was raising a point by asking a question
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Post by sigurdur on Apr 17, 2015 14:55:11 GMT
www.bbc.com/news/science-environment-32348291Although Arctic sea ice set a record this year for its lowest ever winter extent - that was not the case for its volume, new data reveals. Europe's Cryosat spacecraft routinely monitors the thickness of floes in the far north. The thinnest winter ice it has ever seen was in 2013. This February, in contrast, the Arctic floes were about 25cm (17%) thicker on average. The long-term trend is, however, still downwards, the Cryosat team cautions. "Year to year, the numbers will jump about, and it just so happens that we've seen relatively high levels of Arctic sea ice thickness and volume in recent years," said Rachel Tilling from the UK's Nerc Centre for Polar Observation and Modelling (CPOM). Cryosat is a satellite altimetry mission managed by the European Space Agency "But sea ice volume is definitely the number people should watch, because it is the most reliable measure of how much ice is left. It's also what we need to understand the processes that have caused the Arctic climate to change which, in turn, will help us to build more accurate models of what may happen to sea ice in the future," the University College London researcher told BBC News
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Post by acidohm on Apr 17, 2015 20:22:34 GMT
www.bbc.com/news/science-environment-32348291Although Arctic sea ice set a record this year for its lowest ever winter extent - that was not the case for its volume, new data reveals. Europe's Cryosat spacecraft routinely monitors the thickness of floes in the far north. The thinnest winter ice it has ever seen was in 2013. This February, in contrast, the Arctic floes were about 25cm (17%) thicker on average. The long-term trend is, however, still downwards, the Cryosat team cautions. "Year to year, the numbers will jump about, and it just so happens that we've seen relatively high levels of Arctic sea ice thickness and volume in recent years," said Rachel Tilling from the UK's Nerc Centre for Polar Observation and Modelling (CPOM). Cryosat is a satellite altimetry mission managed by the European Space Agency "But sea ice volume is definitely the number people should watch, because it is the most reliable measure of how much ice is left. It's also what we need to understand the processes that have caused the Arctic climate to change which, in turn, will help us to build more accurate models of what may happen to sea ice in the future," the University College London researcher told BBC News It's interesting they intend to make public their results routinely through the winter....more information to pour over!
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Post by missouriboy on Apr 19, 2015 0:41:51 GMT
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Post by graywolf on Apr 19, 2015 9:55:01 GMT
Expect heavy losses over the coming week as the Pacific side finally loses the recent cold and allows the 'warm plume' to begin work in earnest.
Again I appear to need warn folk about the 'quality' of the ice as well as the amounts. As it is prof Barbers attempts to have the sats spot his 'rotten ice' we still rely solely upon eye balling the ice. I still wonder how much of the 2nd/3rd/4th and 5th year ice is 'rotten ice' as we see each Aug/Sept as the research craft work through the high Arctic. The bow cams show us deeply contoured ice full of 'potholes' and larger cavities which, over winter, refreeze with FY ice to produce the kind of ice that has vessels plough through unhindered even though the sat charts show thick multiyear ice.
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Post by Ratty on Apr 19, 2015 10:45:04 GMT
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