Barrow Sea Ice Break-up: Dark Open Water In Late April
The
warming trend that we provided predictive analysis for yesterday has
barely even begun and
we already have visible dark, open water off Point Barrow, Alaska as
of late Tuesday evening on April 29. A large polynya that had
opened up off the northern Alaskan coast has now extended well past
Barrow and landward toward the near-shore waters. By late evening,
the open water had invaded to within about 200 yards of shore along
and past the Point Barrow coastline.
In
broader summary, the open water polynya stretches from Cape Lisburne
to past Point Barrow and measures between 20 and 50 miles in width.
General trends show this large polynya continuing to expand northward
into the Chukchi Sea, a motion that is likely to continue for at
least the next few days.
Some
cooling will likely return after the currently building Arctic
heatwave, but it is questionable if it will be enough to result in a
refreeze given the prevailing and much warmer than usual conditions.
Sea
ice break-up at Point Barrow typically begins in mid-to-late June. It
often involves both the formation of open water offshore as well as
sea ice motion near-shore. Though the polynya removed ice from the
off-shore waters of Point Barrow today, the near-shore ice still
remains grounded, so this admittedly impressive event cannot
technically be considered a break-up. That said, it appears that we
are seeing a very early initiation of melt conditions for the Barrow
region.
With
warmer weather settling in, heat stresses to the local and regional
sea ice will likely continue to ramp up. So, in other words, this
early season melt event has only just begun.
(Large
polynya extending from Cape Lisburne to about 80 miles past Point
Barrow on April 28. The polynya continued to enlarge even as it
invaded the near-shore regions of Point Barrow on April 29th. Image
source: LANCE-MODIS.)
Links:
No comments:
Post a Comment
Note: only a member of this blog may post a comment.