Unprecedented recent summer warmth in Arctic Canada

[numerouno]

Unprecedented recent summer warmth in Arctic Canada


Abstract

[1] Arctic air temperatures have increased in recent decades, along with documented reductions in sea ice, glacier size, and snowcover. However, the extent to which recent Arctic warming has been anomalous with respect to long-term natural climate variability remains uncertain. Here we use 145 radiocarbon dates on rooted tundra plants revealed by receding cold-based ice caps in the Eastern Canadian Arctic to show that 5000?years of regional summertime cooling has been reversed, with average summer temperatures of the last ~100?years now higher than during any century in more than 44,000?years, including peak warmth of the early Holocene when high latitude summer insolation was 9% greater than present. Reconstructed changes in snow line elevation suggest that summers cooled ~2.7?°C over the past 5000?years, approximately twice the response predicted by CMIP5 climate models. Our results indicate that anthropogenic increases in greenhouse gases have led to unprecedented regional warmth.


onlinelibrary.wiley.com/doi/10.1002/2013GL057188/abstract

[sigurdur]

Thanks numerouno. Will be good to read the paper.

[karlox]

A critical view on the paper:

Unprecedent summer warmth in Canada. Other view

[nautonnier]

Nov 3, 2013 4:52:32 GMT numerouno said:

Unprecedented recent summer warmth in Arctic Canada


Abstract

[1] Arctic air temperatures have increased in recent decades, along with documented reductions in sea ice, glacier size, and snowcover. However, the extent to which recent Arctic warming has been anomalous with respect to long-term natural climate variability remains uncertain. Here we use 145 radiocarbon dates on rooted tundra plants revealed by receding cold-based ice caps in the Eastern Canadian Arctic to show that 5000?years of regional summertime cooling has been reversed, with average summer temperatures of the last ~100?years now higher than during any century in more than 44,000?years, including peak warmth of the early Holocene when high latitude summer insolation was 9% greater than present. Reconstructed changes in snow line elevation suggest that summers cooled ~2.7?°C over the past 5000?years, approximately twice the response predicted by CMIP5 climate models. Our results indicate that anthropogenic increases in greenhouse gases have led to unprecedented regional warmth.


onlinelibrary.wiley.com/doi/10.1002/2013GL057188/abstract

You should also read this:

Miller et al.’s “Unprecedented Recent Summer Warmth in Arctic Canada”: Bad assumptions, poor logic, and contrary to other evidence of Arctic temperatures.

"Conclusions

From the foregoing data and analyses, what is abundantly clear is that the Miller et al. paper is so badly flawed with unwarranted assumptions, poorly thought out assertions, and astonishingly bad logic that their conclusion “temperatures of the past century must have exceeded those of any century in more than 44 ka” cannot be considered valid. How could reputable scientists come to such incorrect conclusions? Perhaps the last sentence in their conclusions section gives us a clue: “anthropogenic emissions of greenhouse gases have now resulted in unprecedented recent summer warmth that is well outside the range of that attributable to natural climate variability.” Even if the conclusions in the paper were correct, they wouldn’t prove anything about CO2 as the cause of climatic warming, so this statement suggests that the real purpose of the paper was to push CO2 at the expense of objective science."

[sigurdur]

May also want to ask why only 4 moss proxy samples were used out of over 130.

[sigurdur]

May also want to ask when Baffin Island became the arctic.

[sigurdur]

Read the paper and never could figure out how this got past peer review.

[Andrew]

Nov 3, 2013 14:02:09 GMT sigurdur said:

May also want to ask when Baffin Island became the arctic.

"Here we use 145 radiocarbon dates on rooted tundra plants revealed by receding cold-based ice caps in the Eastern Canadian Arctic"

80% of Baffin Island is in the Eastern Canadian Arctic.

[numerouno]

Code, thank you vey much, but I'm afraid I will be a rare visitor.

[phydeaux2363]

There's a criticism of the Miller paper on WUWT this morning. I haven't finished reading it, but as you would expect given the forum, it rejects Miller's findings.

[sigurdur]

This link was brought to my attention by a friend at the NWS:

ds.data.jma.go.jp/tcc/tcc/products/clisys/STRAT/

[nonentropic]

The word unprecedented indicates unconstrained BS simply because it is also unconstrained.

So we have had 5000years of falling temps in the arctic 2.7C, it gives you real concerns we are entering an ice age now that they have started to rise.

Did they get paid for this work!!!

[sigurdur]

www.climatechangedispatch.com/greenland-ice-melt-is-geothermal-not-manmade.html

[scpg02]

Jan 4, 2015 15:50:10 GMT sigurdur said:

www.climatechangedispatch.com/greenland-ice-melt-is-geothermal-not-manmade.html

Climate science doesn't look for the truth. Ice melting? Look we are right about manmade global warming. Couldn't possibly be geothermal. That doesn't support the policy changes desired.