Well, y'all... I got good news, and I got bad news.
I'll start with the bad news.
A new study from NASA and the University of California-Irvine, has found that a large
part of the West Antarctic Ice Sheet is now melting irreversibly.
Some of you have written us asking what that means, and what exactly is going on down there,
so let's take a look.
The part of the continent they're talking about is called the Amundsen Sea sector, which
contains enough frozen fresh water to raise the global sea level by 1.2 meters.
This water is locked up in glaciers, or huge moving masses of ice, and the glaciers in
this sector are melting faster than scientists expected. Satellite data show that Antarctica
is now losing 159 metric gigatons of ice every year -- the vast majority of it, about 134
gigatons, in West Antarctica.
And according to glaciologists, the Amundsen sector has passed what they call "the point
of no return" which means that nothing can stop it from melting completely.
They know this because glacial melt is basically caught in a positive feedback loop.
See, the Antarctic Ice Sheet doesn't float -- it sits on land. This is good if you're
one of the billion or so people living in low-lying coastal areas somewhere on Earth,
because, in Antarctica, the land is colder than the water.
But those glaciers are always moving, and they're moving down toward the ocean.
The place where a glacier loses contact with solid land and starts floating on the water
is called its grounding line.
And the grounding line isn't always above sea level. The Amundsen Sea sector typically
rests on the bedrock of the ocean floor. In some areas, that's two and a half kilometers
down!
But the new study has found that six of the major glaciers in West Antarctica are now
floating above where they used to be grounded on the seafloor, which means they've thinned,
and their grounding lines have moved inland.
And this just accelerates the melting, because nearly all glacial melt occurs on the underside
of glaciers when they're floating, not on land.
And as the glacier gets lighter and thinner, it starts moving even faster into ocean ... and
you can probably see now why the whole thing has become unstoppable.
Because the grounding lines beneath these six glaciers are under hundreds of meters
of ice, it's hard to tell exactly how fast this is happening. But it is, definitely,
happening. And in the Amundsen Sea sector, it's not going to stop happening until there
is no more Amundsen Sea sector.
Which glaciologists say could happen in the next 200 to 900 years.
We're problem solvers, right? Humans are almost as good at solving problems as we are at creating
them.
Which brings us to the good news: Nesta, an innovation charity based in the UK, has launched
the Longitude Prize, to award 10 million pounds to whoever solves one of the biggest scientific
problems of our time.
It takes its name from the reward offered by the British Government back in 1714 to
any scientist who could solve one of the most vexing puzzles of their day: how a ship at
sea could determine its exact location by measuring its longitude.
The modern Longitude Prize is similar, only instead of figuring out how to orient ships,
it's getting people to make other people's lives better. And instead of a million dollars,
it's a lot more than that.
There are six candidates for this year's Longitude Prize problems, only one of which will be
chosen, and if you live in the United Kingdom, you can vote on which problem you want science
to solve!
One candidate, for example, is green air travel: Since the CO2 emitted by airplanes has twice
the greenhouse effect as ground-based sources, how can we fly without damaging the environment?
There's also a challenge to revolutionize food, and develop an agricultural innovation
that would make nutritious food more accessible while keeping it cheap and sustainable.
Then there are Antibiotics, which we here at SciShow have talked about recently. With
antibiotic resistance on the rise, this prize would go toward a quick, accurate test for
infections that doctors could use to make sure they're giving the right antibiotic at
the right time.
Nearly 1 in 50 people live with some form of paralysis, meanwhile, mostly because of
spinal injury, multiple sclerosis, or stroke. If this category wins, the money would reward
new technology that could restore as much freedom of movement as possible in people
with paralysis.
There's also a chance to have a run at a problem that has stymied scientists for centuries:
finding an inexpensive way to desalinate water, so people can have fresh water without tapping
into the limited amount circulating around the planet.
And finally: One in three seniors will develop some form of dementia, so the sixth challenge
would reward treatments or technology that could allow patients to live independently
for longer.
These are all, of course, worthy questions, and you get to help find an answer. Voting
will remain open until June 25th, when the winner will be announced, so if you live in
UK, vote for the kind of suck that you want science to decrease.
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