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Wednesday, October 28, 2015

Geophysical Research Letters Shock Finding: In 2014 More Multiyear Ice Than Previous Nine Years… Arctic Winter 0.5 – 1.5°C Colder!

Geophysical Research Letters Shock Finding: In 2014 More Multiyear Ice Than Previous Nine Years… Arctic Winter 0.5 – 1.5°C Colder!

By P Gosselin | NoTricksZone | October 27, 2015
Has anyone been wondering why we’ve been hearing so little about the Arctic lately?

New study says Arctic to remain frozen for many more years. MODIS image of the Arctic, Jeff SchmaltzNASA Earth Observatory
Reader Dennis A. sent me the following abstract of a new paper by Haas et al: Ice thickness in the Northwest Passage – Haas – 2015 – Geophysical Research Letters – Wiley Online Library. It turns out that the Arctic is far less ice free than many thought or expected just some years ago. So wrong can the models be!
More Arctic ice and up to 1.5°C colder!
Navigable NWP postponed 40 years!
The study finds that in 2014 “more ice survived the summer as MYI than in the nine most recent years” and it was only “slightly less than during 1968–2015 on average (Figure S5).”
Also “between November 2014 and April 2015, winter air temperatures were between −0.5°C and −1.5°C colder than during 1980–2010.”
Moreover the study also has climate experts profoundly postponing yet another prediction: The Northwest passage will not be navigable for another 40 years… let alone the Arctic becoming ice free!
The entire GRL abstract (emphasis added):
We present results of the first ever airborne electromagnetic ice thickness surveys over the NWP carried out in April and May 2011 and 2015 over first-year and multiyear ice. These show modal thicknesses between 1.8 and 2.0 m in all regions. Mean thicknesses over 3 m and thick, deformed ice were observed over some multiyear ice regimes shown to originate from the Arctic Ocean. Thick ice features more than 100 m wide and thicker than 4 m occurred frequently.
Results indicate that even in today’s climate, ice conditions must still be considered severe. These results have important implications for the prediction of ice breakup and summer ice conditions, and the assessment of sea ice hazards during the summer shipping season.
For further evaluation, it is also important to consider that in Parry Channel, including VMS, i.e., in the waters of the northern NWP, in 2014 more ice survived the summer as MYI than in the nine most recent years but slightly less than during 1968–2015 on average (Figure S5).
Between November 2014 and April 2015, winter air temperatures were between −0.5°C and −1.5°C colder than during 1980–2010 which could have led to slightly thicker level ice than average, notwithstanding snow effects
However, by all means the observed thicknesses and amount of deformed ice still indicate serious ice conditions which can persist throughout the summers and provide ample potential for encounters with hazardous ice. Even in recent years, the CAA remains a source for locally grown MYI and a sink for Arctic Ocean MYI [Howell et al., 2015]; and therefore, shipping through the NWP should not be taken lightly.
These conclusions also support results of Smith and Stephenson [2013] who suggested that the NWP will not become easily navigable for another 40years or so.
In addition, we have observed two ice islands in and south of Byam-Martin Channel in 2011 which were not included in the present analysis. These ice islands originated from the ice shelves along the Arctic Ocean coast of Ellesmere Island, and were between 30 and 40m thick, adding to the variability of hazardous ice features in the NWP.”

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