May,
2017
Another
month has passed and so here is the updated Arctic sea ice volume
graph as calculated by the Pan-Arctic Ice Ocean Modeling and
Assimilation System (PIOMAS) at the Polar
Science Center:
It's
no surprise 2017 is still lowest on record, according to the PIOMAS
model. If during the last week of April the Arctic wouldn't have
cooled down (somewhat) like it did, the gap with previous years
would've grown even bigger. But as it is, things haven't changed all
that much since the end
of March.
The lead over number 2, 2011, has decreased from 1731 to 1642 km3.
The difference with record low year 2012 (at the minimum) is
practically unchanged.
The
annual maximum was also reached in April and I will discuss it below,
but first want to go through the usual graphs shown in this update.
Starting with Wipneus' version of the PIOMAS sea ice volume graph
showing more details:
The
trend line on the PIOMAS sea ice volume anomaly graph has barely left
two standard deviation territory, but as I wrote last
month,
it is exceptional that it's so close to it at this time of the year:
As
for average sea ice thickness (a crude calculation of PIOMAS volume
numbers divided by total JAXA sea ice extent, hence the name
PIJAMAS), 2017 continues to be extremely low:
And
now for that maximum.
Based
on the average of the last 10 years I calculated that this year would
probably end up somewhere around 20795 km3, and it turned out to be a
tad lower: 20756 km3. That means that this past winter saw the lowest
amount of sea ice volume growth after the minimum since 2006 and
2007:
This
makes sense if we look at the sea ice age distribution map that was
posted in yesterday's monthly update on the NSIDC
website,
as sea ice age is an indicator of volume/thickness:
There
is no barrier of multi-year sea ice in the Beaufort Sea whatsoever,
and a lot of three-year ice is poised to be pushed out of Fram
Strait, while the thickest ice could be squeezed through the garlic
press of the Canadian Archipelago again, as well as Nares Strait
(where no arches have formed this winter). Not looking good. Not
looking good at all.
So,
with a maximum that was almost 2000 km3 lower than the previous
record reached in 2011, it's obvious that anything is possible this
coming melting season. Last
month,
I put up some calculations to show where this could go, but the graph
below - created by Jim
Pettit -
is an excellent visual representation:
There
are clearly myriad of ways by which the 2017 melting season could
break 2012's record low minimum.
If
this year's melt is equal to the average of the last 10 years, there
will be around 2500 km3 left in September (mind you, the 2012 record
low minimum is 3673 km3). If there's as much melt as in 2010 or 2012,
this year's minimum will barely go above 1000 km3. I don't want to
know what the Arctic looks like if that should happen.
There's
nothing else to do but hope that PIOMAS has it completely wrong, or
else pray for lots of cold and cloudy weather in the Arctic this
summer.
No comments:
Post a Comment
Note: only a member of this blog may post a comment.