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Humans are causing massive changes in water all over Earth, NASA says

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A 14-year NASA mission has confirmed that a massive redistribution of freshwater is occurring across the Earth, with middle-latitude belts drying and the tropics and higher latitudes gaining water supplies.

The results, which are probably a combination of the effects of climate change, vast human withdrawals of groundwater and simple natural changes, could have profound consequences if they continue, pointing to a situation in which some highly populous regions could struggle to find enough water in the future.

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“To me, the fact that we can see this very strong fingerprint of human activities on the global water redistribution, should be a cause for alarm,” said Jay Famiglietti, a researcher at NASA’s Jet Propulsion Laboratory and one of the authors of a new study published in Nature on Wednesday.

The results emerge from the 2002-2016 GRACE mission, which is short for Gravity Recovery and Climate Experiment, supplemented with other additional data sources. The GRACE mission, which recently ended but will soon be replaced by a “Follow-On” endeavor, consisted of two twin satellites in orbit that detected the tug of the Earth’s gravity below them – and monitored mass changes based on slight differences in measurements by the two satellites.

Among all the very massive features on the Earth, water and ice are the ones that change most regularly. Thus, the GRACE data have been used to detect anything from the vast losses of ice in Greenland, Antarctica and Alaska, to changes in ocean currents, to the scale of the California drought.

The new research, led by NASA’s Matthew Rodell, pulls together these and other findings to identify 34 global regions that either gained or lost more than 32 billion tons of water between 2002 and 2016. As the study notes, 32 billion tons is about the amount of water contained in Lake Mead. So all 34 areas saw very large changes.

The resulting map of the findings shows an overall pattern, in which ice sheets and glaciers lose by far the most mass at the poles, but at the same time, middle latitudes show multiple areas of growing dryness even as higher latitudes and the tropical belt tend to see increases in water.

The study emphasizes that the 34 separate changes that it detects do not all have the same cause – not even close.

There’s very strong suspicion that the melting of glaciers and ice sheets is tied to climate change. On land, it’s possible that some droughts and rainfall increases may be also, though the study is cautious about that, noting that natural variability can also be a major factor here.

Still, the idea of mid-latitude drying and higher- and lower-latitude wetting is a common feature of climate change models. “We only have 15 years of data from GRACE, but it sure as heck matches that pattern, it matches it now,” said Famiglietti. “That’s cause for concern.”

Further data from a new launch of the GRACE “Follow-On” mission will contribute to a longer data record that may help better identify trends, Famiglietti said.

And then there are other human induced changes, relating not to climate change but rather to direct withdrawals of water from the landscape.

Thus, in northern India, the northern China plain, the Caspian and Aral Seas, among other regions, human withdrawals for agriculture have subtracted enormous amounts of water mass from the Earth. The changes in the Aral Sea region, previously documented by NASA, have been particularly intense.

There are also some major cases of humans increasing water storage in the landscape, particularly in China, where massive dam construction has created enormous reservoirs.

Mainly, though, what’s striking about the map is the way that a combination of human-driven water withdrawals and droughts seem to be punishing the central latitudes of the northern hemisphere in particular, but also the southern hemisphere to a significant extent.

“I think we have forgotten, society has forgotten, how much water it takes to produce food,” Famiglietti said. “We’ve taken its availability for granted. And you know, now we’re at a point in many of these aquifers where we can’t take it for granted any more. Population is too great, groundwater levels are too low . . . we’re at tipping points.”

Still, it’s important to bear in mind that, while the GRACE data have given a new panoptic view of the changing distribution of water around the globe, the data remain coarse and the causes behind the trends in many cases remain a matter of interpretation, cautioned Peter Gleick, an expert on climate change and water who is president emeritus the Pacific Institute.

“Without a doubt the GRACE system proved that we can see very significant changes in water storage around the planet,” said Gleick. “Figuring out what drives those changes, is a harder thing.”

The next GRACE satellite mission will provide still better data, he agreed.

“We’re in this transition between not really having a global overview, and someday having an incredibly high-resolution sophisticated remote sensing overview,” Gleick said. “That’s where we are.”

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This Brilliant Interactive From NASA Lets You Virtually Explore Planets Far, Far Away

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Ever dreamt of stepping onto a faraway planet? Well, NASA has you covered with this incredible virtual planet simulator.

The Exoplanet Travel Bureau drops you into vastly different star systems to explore distant worlds.

You can enjoy Trappist-1e’s blood red sky, a planet we now know has a large iron core.

(NASA/Exoplanet Travel Bureau)

The Trappist system has seven planets, and caused huge hype last year about possible water and Earth-like worlds only 40 light years away.

Or fly over onto planet Kepler-16b – part of a ‘Tatooine-like’ system 200 light years away, and the largest planet ever discovered orbiting two stars.

And it is huge – with a mass and radius nearly identical to Jupiter.

kepler 16b nasa toolKepler-16b (NASA/Exoplanet Travel Bureau)

You can even enjoy the brand new sights of Kepler-186f with NASA’s tagline “Where the grass is always redder”.

Kepler-186f is not in the same system as Kepler-16b, despite the similar names.

As NASA explains on its exoplanet website, it was “the first validated Earth-size planet to orbit a distant star in the habitable zone – a range of distance from a star where liquid water might pool on the planet’s surface.”

Keplar-186f is orbiting a star much cooler and redder than our Sun over 500 light years away, and despite the fancy explorer tool, we aren’t even sure if it has an atmosphere yet.

kepler 186f nasa toolKepler-186f (NASA/Exoplanet Travel Bureau)

And that’s really important to note, and NASA spells it out on every planet it drops you into.

We haven’t explored these systems, we have no images of any of these planets, and the amount of data we have on even our closest exoplanet friends are still extremely limited.  

As astrophysicist Jonti Horner and Brett Addison explained on The Conversation: “Most of the exoplanets found to date have been discovered by two key methods: either watching stars to see if they wobble, or to see if they wink.”

Not exactly the incredibly detailed information and pictures we’ve been receiving from Jupiter, Mars, or Pluto.

So, we’re still very far off seeing what they actually look like, let alone visiting them in person. But at least we can enjoy the virtual sights thanks to NASA – apparently these even work in one of those fancy virtual reality headsets.

You can explore the Exoplanet Travel Bureau here.

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Sunscreen ban seeks to protect coral reefs

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The Hawaii legislature has passed a ban on sunscreens containing chemicals believed to harm coral reefs.

Hawaii is the first state to prohibit the sale and distribution of sunscreen with oxybenzone and octinoxate, which scientists have discovered contributes to coral bleaching when washed off in the ocean.

The state legislature considered a similar bill in 2017 but it stalled out before passage. This year it made it through both houses, and now awaits the signature of Gov. David Ige. The new rules are not set to take effect until Jan. 1, 2021.

Reefs around the globe, from Australia’s Great Barrier Reef to Haunama Bay in Hawaii and off Florida’s southern coast, have suffered serious damage in the last few years after consecutive bleaching events. Bleaching occurs when corals are stressed by warmer-than-average water temperatures and other factors, and the colorful photosynthetic algae that live inside, zooxanthellae, are expelled. The coral cannot survive without the symbiotic relationship, and when ocean temperatures do not return to normal quickly enough, the reefs may die. Pollution, including sewage and agricultural runoff, are serious threats to reef heath, as well, but switching sunscreens is one way swimmers and those who enjoy the ocean can have an impact, proponents of the ban say.

A 2015 study from the Haereticus Environmental Laboratory, a nonprofit research group, indicated oxybenzone, a common UV-absorbing chemical found in sunscreens, can poison coral in multiple ways. It contributes to bleaching, hinders reproductive growth and causes coral deformities.

Researchers estimate 14,000 tons of sunscreen infiltrates the world’s oceans each year, with highest concentrations in popular, accessible reef areas in Hawaii and the Caribbean. A 2015 Haereticus survey of Trunk Bay beach on St. John found anywhere from 2,000 to 5,000 swimmers daily, and estimated over 6,000 pounds of sunscreen was deposited on the reef each year. At Hanauma Bay on Oahu, which attracts an average of 2,600 swimmers daily, an average of 412 pounds of sunscreen was deposited daily on the reef.

The Hawaii hospitality industry has jumped into the campaign to preserve the Aloha State’s reefs and spread the word about reef-safe sunscreens. Hawaiian Airlines has been distributing samples of reef-safe sunscreen on flights bound for the islands.

Aqua-Aston Hospitality launched the “For Our Reef” program in 2017. The company is installing reef-safe sunscreen dispensers on their properties, offering sunscreen trade-ins, and organizing beach cleanups and awareness campaigns.

“This is a huge win for Hawaii. We are proud of the role Aqua-Aston Hospitality played to raise the volume on this issue, by lending our voice and bringing a greater awareness that by choosing the right sunscreen it’s possible to protect your skin and help preserve the reef,” Theresa van Greunen of Aqua-Aston Hospitality said. “We have a responsibility to take positive steps  to create a culture of sustainability and protect the Hawaii we love.”

At the end of 2017, Napili Kai Beach Resort on one of Maui’s reef-protected bays on the north side of the island introduced an educational program to encourage visitors to use reef-safe sunscreens. The resort offers each guest a free sample of reef-safe sunscreen, made with minerals such as zinc oxide and titanium dioxide that are non-nano, particles larger than 100 nanometers, because anything smaller can be ingested by corals. They also offers coupons for the purchase of reef-safe sunscreen and educational materials.

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New space strategy to be unveiled 'in the coming months': Bains

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MONTREAL — A new Canadian space strategy that is already at least one year behind schedule is only months away, Science Minister Navdeep Bains said Friday.

“We haven’t determined the exact date, but it will be as soon as possible,” he said.

“In plain English — in the coming months.”

Bains made the comments after announcing an investment of more than $26.7 million in space technology that will benefit 33 Canadian companies.

The new money will create or secure 397 jobs and support 46 projects to develop what are described as game-changing technologies in medicine, artificial intelligence, autonomous navigation and virtual reality.

“Thanks to the new technologies, we will be able to improve wildfire monitoring, weather predictions and to better understand climate change,” Bains said.

Bains, who was joined by Canadian astronaut Jeremy Hansen, made the funding announcement at MDA’s Sainte-Anne-de-Bellevue facilities on the western tip of the island of Montreal.

MDA, which builds the Canadarm and satellites, will receive about $4 million to improve its technologies. That money is being awarded through a Canadian Space Agency program geared to small- and medium-sized firms.

Bains was also given a tour of three Radarsat satellites that are expected to be launched in November.

Another date that has yet to be determined is Hansen’s first space voyage.

Fellow astronaut David Saint-Jacques is due to blast off in December on a six-month mission to the International Space Station.

But exactly when Hansen will follow him is, in his own words, “the million-dollar question.”

It has already been announced he will fly by 2024.

Hansen strongly indicated his future flight will be on commercial space capsules currently being developed by two American companies — SpaceX’s “Dragon” capsule and Boeing’s “CST-100 Starliner.”

“We have to get those flying first and then I’ll have some resolution on when I’ll fly,” Hansen said.

“I haven’t been part of actually testing those systems yet. But I will in the future, so it’s pretty exciting stuff.”

The only way any astronaut can currently travel to and from the space station is on board a Russian Soyuz space capsule.

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