Big Melt This Week In Greenland Is Bad, But Not (Yet) The End Of The World

Orange areas are spots in Greenland that
experienced melting on Thursday. That's
a very unsually large area for this
early in the season.

This sounds dire: Just on Wednesday, two billion tons of ice melted off of Greenland.

To put it in perspective, though, the two billion tons of ice that melted off of Greenland in one day is certainly very bad news, but it doesn't mean the whole ice sheet will go away in a flash. The vast, vast majority of the ice is still obviously very much there in Greenland.

But still. Forty-five percent of the Greenland ice sheet surface was melting Wednesday, which is pretty much the most anybody has seen this early in the season.  Temperatures were as much as 40 degrees above normal in Greenland, notes the Washington Post.

A very high elevation weather station in Greenland, aptly named Summit, briefly went above freezing this week. Thaws are rare at Summit. The last time it happened was in July, 2012, the Washington Post notes.

Much of the thawed ice that didn't manage to flow into the oceans will refreeze in cooler days ahead, but the initial thawing has weakened some of the ice, making it more prone to melting if it gets warm again later this summer.

Climatologists always worry about Greenland's ice sheet. As it melts off, it flows into the ocean and raises global sea levels. This year, the melt season in Greenland is definitely off to a bad start. It could rival the big melt of 2012, which is the benchmark for Greenland thawing.

Then again, the weather patterns might change and the melting could slow.  The fact that melting started in some corners of Greenland in late April amid record warmth, and the thaw continued off and on through May and the first part of June is ominous.

Arctic sea ice extent is so far at record low levels for this time
of year. This trend might or might not continue, depending upon
weather conditions in July and August. 

The bulk of the summer season thaw in Greenland is in July. Now that there has already been some thawing, much of the freshest, whitest snow atop the ice has gone away.

That leaves relatively dirty ice exposed, which attracts more of the sun's heat than pure white stuff. Which in turns means the risk of faster melting.

This latest melting episode in Greenland seems to be a case of climate change teaming up with a natural weather pattern.

The dreaded negative phase of what is known as the North Atlantic Oscillation is going on at the moment.

That pattern creates warm, sunny high pressure systems to sit over Greenland (and at the same time pushing chilly air southward into the mid-latitudes. This can help make it cool and cloudy here in Vermont. I bet you noticed that during this spring.)

Climate change is probably making what would already have been an odd warm spell in Greenland a little bit warmer.

It's not just Greenland that's been a toasty Arctic spot lately. Arctic sea ice is at its lowest level for mid-June since satellites started monitoring it in 1979, the Washington Post tells us.

Ice loss in the Chukchi and Beaufort seas along Alaska's northern coast is "unprecedented, said Rick Thoman, a Fairbanks-based climatologist.  Since so much water is already exposed, the sun will have a chance to warm the water, which could encourage further record-level ice melting  near the North Pole.

If a lot of ice melts in the Arctic Ocean, that won't raise sea levels like Greenland's melt would.  The melting Arctic Ocean ice is like ice cubes melting in your glass of gin and tonic. The water level won't change. Greenland's melt is like a colander filled with ice held over the glass. The thawing ice would drip into the glass, eventually causing it to overflow.

With or without climate change, Arctic weather is highly variable. There's always a chance the weather in the far north could turn cloudier and cooler for the rest of the summer. That would prevent this year from being another record melt, like 2012 was. We'll just have to wait and see on that one.