Okay, we were talking about the sea and what climate change is doing to
it. My examples last time were in Europe and the US, in the northern temperate
zones. Now I want to consider all that ice and water in the extreme north and
south, around the poles.
If you’ve been paying attention, you might remember news of huge chunks
of Antarctic ice breaking away. I’m talking chunks bigger than some states.
Antarctica is receiving warmer weather than it’s seen in millennia, or maybe
even millions of years. Some coasts that certain types of penguin have called
‘home’ for countless generations are becoming inhospitable for them. They
already live at the bottom of the world, where are they supposed to go from
there?
The Arctic Ocean is not doing any better. There is no land under all
that ice at the north pole, just water. You might think, ‘That’s okay, because
it takes a lot of energy to warm water up.’ Yes, it does. And yet, that water
under that thick sheet of ice has
warmed up.*
If you look at a map or globe, you’ll see a bunch of islands above
Canada. During Europe’s Age of Exploration, several well-provisioned ships made
attempts to find a ‘Northwest Passage’ during the summers, trying to find a way
to get around the Americas to do trade with the Orient. I don’t remember
hearing of any of those excursions ever making it through, nor of any making it
home again. At that time, I understand, whatever open channels of water that
could be found among all those islands were unreliable and tended to close up
and freeze a ship in place, even in summer. The last few years, so much of that
ice has melted during the summer, that some cruise lines have offered cruises
from one coast to the other, via the Canadian passage.
Something has happened to the Beaufort Gyre. That is a 60-mile-diameter
pool of cold freshwater and sea ice located north of Alaska. It used to spin
clockwise for 5-7 years, then slow down and start spinning in the opposite
direction. This change in direction was caused by periodic cyclones that moved
from the Northern Atlantic Ocean into the Arctic Ocean. But the North Atlantic
has been warming up even faster than other parts of the world, and has failed
to get the Beaufort Gyre to change direction in a dozen years or more.
So it’s just been sitting there, spinning and getting larger. And
although it contains ‘cold’ water, that’s a matter of relativity. This spinning
water contains twice as much heat now as it did 30 years ago. But it’s not
sitting on top, like you’d think it would. It extends so deep, it is creeping
under the Arctic ice sheet, which I understand can be a mile or more thick.
Once it starts melting that ice sheet from below, well, how long before that
ice sheet starts to break apart into gigantic icebergs, like the Antarctic ice
has already started doing?
And what happens when all that ice breaks up and melts? Right, it
raises sea level, which we discussed last time.
I had never heard of the Beaufort Gyre until a couple days ago, but I’m
not done with it. From what I’ve been reading, whether it continues its current
spin or starts going the other way, somebody’s in for a nasty time. Maybe it
will come up next time.
* https://www.dailykos.com/stories/2018/9/5/1792312/-Warm-ocean-water-has-penetrated-deep-into-the-Arctic-interior-portending-year-round-loss-of-sea-ice
