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Scientists predict that the Artic will be completely devoid of ice by 2040

NASA and the National Snow and Ice Data Center (NSIDC) have been closely monitoring the amount of ice found in the northernmost part of the world for almost 40 years. On March 17, the Artic Ocean reached its peak level of ice coverage for the rest of the year, and it was surprisingly low, writes Danny Paez for Inverse Science.  The sea ice floating over the North Pole covered only 5.59 million square miles, which is the second lowest maximum measured since 1981, writes Paez.

In a statement released Monday, Claire Parkinson, senior climate scientist at NASA’s Goddard Space Flight warned of this dangerous trend. “The Artic sea ice cover continues to be in a decreasing trend and this is connected to the ongoing warming of the Arctic.”  Consistent rates of ice disappearance support scientists’ prediction that the Arctic will be completely devoid of ice by 2040.  The sea ice blanketing the North Pole used to go through a predictable cycle of expansion and shrinkage, reaching its maximum yearly extent between February and early April, and melting to its lowest point in September.  This is no longer the case, observations show the Artic sea ice declining during both the melting and growing seasons, prompting a host of negative side effects to plants and animals that rely on the frost.

“It’s a two-way street,” says Parkinson. “The warming means less ice is going to form and more ice is going to melt, but also, because there’s less ice, less of the sun’s incident solar radiation is reflected off, and this contributes to the warming.”  NASA plans to launch the Ice, Cloud and Land Elevation Satellite -2 (ICESat -2) this fall, which will continuously monitor the Arctic Ocean.

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Scientists drill in Antarctica to discover what happened the last time it melted

An international team of geologists and climate scientists are drilling off the coast of West Antarctica to find out why glaciers there melted millions of years ago, and how it could relate to what is happening today. The project began in early January and extends through March, reports Eric Betz for Discover Magazine. The International Ocean Discovery Program’s JOIDES Resolution, led by Amelia Shevenell of the University of South Florida, will drill five core samples reaching thousands of feet below the Ross Sea. These cores will allow scientists to read layers in the rock record, providing information on climate and ice conditions that stretch back tens of millions of years.

“We can combine all that data and try to understand times where ocean temperatures were   warm, and we can look at times where oceans weren’t as warm,” says Shevenell.

Scientists are confident that conditions today result from warm ocean water hailing from northern climes washing up toward the coast of Antarctica and finding its way beneath ice sheets, melting them from below. The IODP drilling expedition aims to better understand what made these ice sheets melt in the past, particularly whether warming ocean waters back then were the cause. Scientists hope to explore the time period called the Miocene (between 7 and 14 million years ago) when Earth’s temperature and atmospheric CO2 levels were similar to what we’re experiencing today. Shevenell says that during that time in Antarctica the ices retreated significantly and caused sea level rise.

“We’re going to begin to understand a lot more about Antarctic ice sheets and how they respond to atmospheric and oceanic changes,” she says.

Once drilling efforts are complete, the IODP team will bring the cores back for more intensive study.

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New aquatic robot looks and moves like a real fish

Scientists have created a realistic robotic fish that mimics the shape and movement of real aquatic life. In a study published Wednesday in Science Robotics, the authors describe the latest version of aquatic biomimetics—a robot design that mimics the shape and movements of real animals. SoFi, (short for soft robotic fish), is described by its creators as a robot fish that blends in, unnoticed, among the underwater crowds.

“We were excited to see that our fish could swim side by side with real fish, and they didn’t swim away,” shares Daniela Rus, lead researcher at the Computer Science and Artificial Intelligence Laboratory at MIT.

According to reports, it is the first robotic fish to contend with currents and pressures of an ocean setting for an extended period of time. In the study, the authors describe how SoFi can nimbly navigate a coral reef in three dimensions, swimming up, down, left, right and forward. A diver using an acoustic communication modem controls SoFi remotely, and, reports Rus, could be an extraordinary tool for studying marine biology.

According to the study, building a robot that can function underwater comes with unique challenges. Besides issues of communications (radio frequencies used to communicate with robots on land don’t work in the water), Rus said buoyancy was among the biggest challenges for her team.

“If you’re a diver then you know you let the air out of your dive vest when you go down and put it in when you go up. But sometimes as you go up the air you have expands so you need to let more out. It’s really quite tricky,” she says.

Rus and her team resolved this issue by creating a buoyancy control unit, with urethane foam chambers that can change their density by compressing or decompressing air. Ken Smith, a marine ecologist at the Monterey Bay institute who didn’t work on the study, believes that this new robotic fish has a lot of potential. He predicts that future improved versions will be very valuable to marine scientists studying shallow-water ecosystems.