Antarctic Krill Under Ice Copyright © Marlo Garnsworthy 2017
Earlier this week, I thought this might be a quieter week in ice news. In fact, it has been anything but. Some of this news is very cool, and some may make you uncomfortable. Hopefully, it will inspire you to fight for our planet’s vital ice, for our oceans, and for our global climate.
Sea ice in the Arctic may be declining faster than previously thought. This GIF posted by Zack Labe will shock you:
The National Snow and Ice Data Center is reporting lower than average ice extent for this time of year.
The Norway Ice Service, too, is consistently reporting lower than average ice extent.
Scientists who drilled through sea ice were surprised to find an adult jellyfish (Chrysaora melanaster) drifting by. Scientists had previously assumed that only polyps (which release tiny baby jellyfish in the spring) survived the winter. Check it out! Amazing!
The sea ice at McMurdo Station has broken out earlier than usual.
Mark Brandon notes that a new polynya (an area of open water within the sea ice) has formed by the Rydberg Peninsula. Check out his cool GIF demonstrating this. He says this is fairly normal for this time of year and that it is a latent-heat polynya. A latent heat polynya is a coastal polynya, and it’s formed as winds push sea ice away from land. He tells me a much larger polynya has formed by the Dotson Ice Shelf, just as it did last year.
Brandon also suggests that the massive Weddell polynya, which has made the news the world over, will only be visible for about two more weeks, after which the sea ice will have retreated. This is a sensible-heat (or open-ocean) polynya, formed by the upwelling of warm water toward the surface, and after the ice has retreated, the processes that formed it will still be operating. (The Weddell polynya is the yellow patch within the dark red ice cover in the image above.)
Simon Gascoin produced this great GIF that shows the drifing of the Weddell polynya and surrounding sea ice.
The Weddell polynya could help us understand changing circulation currents in the Southern Ocean caused by Climate Change.
Land ice is formed by layers upon layers of snow, which become compacted over time. A new study discussed in this Scientific American article suggests that a combination of greater katabatic winds (downward and often very strong winds) and warmer air over Antarctica could reduce the amount of snow falling.
Like giant rivers of ice, glaciers flow toward the sea. The Thwaites and Pine Island glaciers are accelerating rapidly. The speed of the Pine Island ice shelf (the floating ice where the glacier meets the sea) increased by 75% (between 1973 and 2010) due to warmer waters in front of it and increased calving of icebergs. (More on those in a moment.)
See GIFs of these glaciers by Simon Gascoin (which I’ve been unable to embed here, alas).
And then there was this, which had the ice scientists on Twitter abuzz this week.
Earlier in the week, we got this great image of huge iceberg B-44, which calved from the Pine Island Glacier back in September.
Just when I thought there’d be no other significant news about icebergs this week, the US National Ice Center NOAA reported that this same iceberg has broken up into pieces too small to be tracked.
WOW! This blows my mind. When B-44 calved a few short weeks ago, it was three times the size of Manhattan. Is it normal for such a massive iceberg to beak up so quickly? I asked Stef Lhermitte.
Note: PIG = Pine Island glacier
A-86A on the other hand is still largely intact.
And I was excited to come across this list of tabular icebergs. Icebergs are either tabular or non-tabular. Tabular icebergs have steep sides and a flat top and can be very large—or downright enormous. They’re formed by ice breaking off an ice shelf. The largest tabular iceberg on record is B-15 (which calved in 2000). It was a whopping 11,000 sq. kilometers (4,200 sq. miles) or almost as big as Connecticut.
What happens to a huge iceberg like B-15 over time? NASA’s Earth Observatory shared that with us this week, plus this fab image of four huge icebergs near the Weddell Sea.
Effects on Marine Life
Warmer and more acidic waters are evicting their inhabitants.
More acidic oceans will affect all marine life.
As sea ice melts, walruses are forced to spend more time on land. This effect of Climate Change has had terrible consequences in Siberia with the death of hundreds of walruses, which were driven off a cliff by polar bears.
And in a devastating blow, there will be no new marine sanctuary in the Antarctic. Tragic.
An Australian research team has determined that coal use will have to be “pretty much” eliminated by 2050 to have any chance of stopping sea level rise.
New York could see bad flooding more often.
And while this is not ice news, I felt it important to bring attention to a local story with far-reaching implications. This week in Rhode Island, three EPA scientists, who were slated to speak at a conference about (among other things) the effects of Climate Change on Narragansett Bay and its watershed and this report, were prohibited from speaking by the EPA. This news made The New York Times and The Washington Post among others. The Executive Director of Save the Bay made this statement. Happily, this story even caught Stephen Colbert’s attention, bringing this travesty to a much wider audience:
As always, I am not a scientist, just a writer/illustrator and science communicator passionately in love with sea ice. I welcome input and corrections by polar scientists as I learn more about this remarkable and vital part of our planet and bring this knowledge to a wider audience.