Strange,
super-hot temperatures at the Arctic mean that sea ice is melting
The
ice should start coming back over the last few weeks, but it hasn’t
Andrew Griffin
@_andrew_griffin
Strange events in
the Arctic appear to suggest that something very troubling is
happening with the sea ice there, scientists have said.
The North Pole is
experiencing hugely unexpected hot sea temperatures, which are
stopping the usual ice from forming and could be a mark that
something global warming is having even more worrying effects than
previously thought.
In most years, the
sun goes down in mid-October and that serves as a signal that the sea
ice will start coming back as the water freezes. But this year that
ice is actually melting, because intense heat is stopping the usual
processes from happening.
Scientists say that
heat has never been seen in previous years and is “off the charts”
when compared with what has happened before. Temperatures have been
as much as 20C hotter than where they usually should be.
Part of that is the
result of cold weather over northern Russia that’s on its way to
the Arctic. When it arrives there, the freezing should begin and much
of the ice that should already be there will appear.
But because of that
effect, there’s likely to be problems over the next year because
the ice will be thinner. And the hot air itself is likely to cause
strange weather, with the cold air being pushed further south.
The unusual melting
and lack of freezing doesn’t necessarily mean that scientists have
underestimated the extent of climate change so much as the effect
that climate change will have on sea ice.
The concern about
the planet’s poles is actually worry about two effects. In the
Arctic, the sea ice recovery usually happens around this time, and
isn’t; but in the Antarctic, sea ice levels are also falling far
more quickly than would usually be expected.
Antarctica would
usually lose sea ice during this period, but it is melting far
quicker than expected. That’s thought partly to be the result of
climate change, but also is happening because of the effects of the
El Nino that wreaked havoc on the world’s weather last year.
Climate scientists
have traditionally resisted using the amount of sea ice as a measure
of the climate, in part because it underestimates the effects.
“Lumping the two
together has been a climate denier tactic in the past to mask out the
sharp drop in Arctic sea ice in recent years,” wrote meteorologist
Eric Holthaus.
Mr Holthaus also
wrote that climate change might actually lead to more sea ice in the
coming years.
“On the one hand,
increased ice mass loss and freshwater output from Antarctica may
actually lead to increased sea ice in the next few decades because
freshwater freezes more quickly than saltwater. On the other hand,
temperatures are going up—not good news if you're an ice cube.”
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