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(0:12) Well y'all, I got good news and I got bad news. Let's start with the bad news.

(0:16) A new study from NASA and University of California Irvine has found that a large part of the west antarctic ice sheet is now melting irreversibly.

Hank: Some of you have written us to ask exactly what that means and what exactly is going on down there, so let's take a look.

Hank: Part of the continent we're talking about is the Amundsen Sea sector which contains enough frozen fresh water to raise the global sea level by 1.2 meters.

Hank: 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.

Hank: 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.

Hank: And according to glaciologists the Amundsen sector has passed what they called "the point of no return", which means that nothing can stop it from melting completely.

Hank: They know this because glacial melt is basically caught in a positive feedback loop , so 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. 

Hank: But those glaciers are always moving and they're moving down towards the ocean. The place where the 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.

Hank: The Amundsen sea sector typically rests on the bedrock of the ocean floor. In some areas, that's 2 and a half kilometers down, but the new study has found that 6 of the major glaciers in West Antarctica are now floating above where they used to be grounded on the sea floor, which means they've thinned and their grounding lines have moved inland.

Hank: And this just accelerates the melting, because nearly all glacial melt occurs on the underside of glaciers when they're floating, not on land.

Hank: And as the glacier gets lighter and thinner, it starts moving faster into the ocean and you can probably see now why the whole thing has become unstoppable.

Hank: Because the grounding lines beneath these 6 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.

Hank: 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.

Hank: Which brings us to the good news... NESTA, an innovation charity based in UK has launched the Longitude Prize to award 10 million pounds to whoever solves one of the biggest scientific problems of our time.

Hank: It takes its name from the reward offered by the British Government back in the 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.

Hank: 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.

Hank: And instead of a million dollars, it's a lot more than that. There are 6 candidates for this year's Longitude Prize's problem, only one of which will be chosen and if you live in UK you can vote on which problem you want science to solve.

Hank: One candidate , for example, is Green Air Travel, since this CO2 emitted by airplanes has twice the greenhouse effect as ground based sources, how can we fly without damaging the environment?

Hank: It'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.

Hank: 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.

Hank: 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. 

Hank: There's also a chance to have a run at the problem that has been bothering scientists for centuries : finding an inexpensive way to desalinate water so people could have fresh water without tapping into the limited amount circulating around the planet.

Hank: And finally ... 1 in 3 seniors will develop some form of dementia so the 6th challenge would reward treatment toward technology that could allow patients to live independently for longer.

Hank: 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 the UK , vote for the kind of suck that you want science to decrease.

Hank: Thanks for watching SciShow news. If you wanna keep learning more about the world and helping to make it more awesome, just go to Subbable.com and become a contributing member.

Hank: Don't forget to go to YouTube.com/SciShow and subscribe.

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