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Gökdeniz Karadağ
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An amazing solution to cooling system energy use.
Possibly the most exciting TED talk I've watched all year! It really seems to be a revolutionary technology. What a time to be alive :)
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Tuatara for today's #joinindaily with +Johnny Wills them of "Reptiles!"

This one was photographed at Nga Manu Nature Sanctuary in Waikanae. While it is a reptile, it's closest relatives are a bunch of dinosaurs that died out around 40 million years ago.
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Account of an amazing trip, full of firsts for civilian aviation.
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On December 1st, 1941, Pan Am flight 6039 set off from San Francisco, California, to Auckland, New Zealand. It followed a typical route for the day: SFO to LAX, LAX to Honolulu, Honolulu to Kiribati, Kiribati to Fiji, Fiji to New Caledonia, New Caledonia to Auckland, and prepared for its return journey.

Except that just as they departed New Caledonia for the way home, they received a radio message: PEARL HARBOUR ATTACKED. IMPLEMENT PLAN A.

"Plan A" would take them on an unprecedented route, returning home not via Honolulu, but via Australia, Indonesia (then the Dutch East Indies), Sri Lanka (then Ceylon), Pakistan (then British India), Bahrain, Sudan, the DRC (then simply the Congo), Brazil, Trinidad and Tobago, and finally, on January 6th, 1942, by radioing a very surprised tower operator at La Guardia airport, as the first passenger aircraft to ever circumnavigate the globe.

The story is simply amazing — and hair-raising, as it involved the seaplane doing a great many things that it was never, under any circumstances, intended to do.

(For those wondering: The precise outgoing route was SFO-LAX-HNL-CIS-SUV-NOU-AUK. On the way back, they flew from NOU to Gladstone, Queensland; Darwin, NT; a Dutch military base in Surabaya, Dutch East Indies (no IATA code that I can find); Trincomalee, Ceylon; Karachi, British India; Bahrain; Khartoum, Sudan; Leopoldville, Congo; Natal, Brazil; Port-of-Spain, Trinidad and Tobago; and finally New York. (NOU-GLT-DRW-Surabaya-TRR-KHI-BAH-KRT-FIH-NAT-POS-LGA-holy crap)
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How can we save ourselves?

Since we've waited so long to do anything, most scientists now think we need to suck carbon dioxide from the atmosphere to prevent dangerous amounts of global warming. But how? The picture shows 6 ways.

Julia Porter wrote an article in Science about one of these ways: bioenergy with carbon capture and storage, or BECCS. The idea is to grow plants for fuel — but when you burn them, bury the carbon dioxide underground.

Like all 6 ways, this has its problems. A recent study showed that BECCS could use a Lake Michigan of water each year — and eat up a quarter of the world's annual nitrogen fertilizer.

But politicians who care about global warming are starting to assume we'll do BECCSS in the second half of this century... because lots of studies assume that's what we'll do!

It may in fact be the best way out of a bad situation. But we should try to think clearly, not just blunder into things... as we've been doing so far.

Here's the basic idea of Porter's article:

In 2015, the Paris climate agreement established a goal of limiting global warming to "well below" 2°C. In the most recent report of the Intergovernmental Panel on Climate Change, researchers surveyed possible road maps for reaching that goal and found something unsettling: In most model scenarios, simply cutting emissions isn't enough. To limit warming, humanity also needs negative emissions technologies that, by the end of the century, would remove more carbon dioxide (CO2) from the atmosphere than humans emit. The technologies would buy time for society to rein in carbon emissions, but they also give policymakers an excuse to drag their feet on climate action in the hopes that future inventions will clean up the mess. One particular technology has quietly risen to prominence, thanks to global models. The idea is to cultivate fast-growing grasses and trees to suck CO2 out of the atmosphere and then burn them at power plants to generate energy. But instead of being released back into the atmosphere in the exhaust, the crops' carbon would be captured and pumped underground. The technique is known as bioenergy with carbon capture and storage, or — among climate wonks — simply as BECCS. Although BECCS is relatively cheap and theoretically feasible, the sheer scale at which it operates in the models alarms many researchers.

As her article points out, all approaches to actively removing CO2, or otherwise cooling the Earth, are a gamble. Politicians may be fooling themselves by hoping that scientists will save the day:

David Keith, who has since helped launch a direct air capture company, says the modelers seized on BECCS because it was one of the few ways to simulate negative emissions — and negative emissions were one of the few ways to try to keep warming below 2°C.

Modelers stress that scenarios are not projections of the future, and shouldn't be treated as such. “They're what-if pathways,” says Katherine Calvin of the Pacific Northwest National Laboratory in College Park, Maryland. But Keith says that hasn't stopped BECCS from attracting undue attention. The result, he says, is a perilous mismatch between models and reality that presents a “moral hazard” by committing future generations to technological solutions that may not work in the end.

It's an accusation that has often been lobbed at Keith's main area of study: geoengineering Earth's climate to counteract warming by, for instance, injecting particles into the sky to reflect sunlight. Keith is miffed that many policymakers see geoengineering as a “completely crazy, risky, way-out-there thing we shouldn't talk about” while remaining sanguine about massive reliance on negative emissions. “If moral hazard is sweeping the problem under the rug, and pushing more of it to future generations, and making it look like you are meeting the targets when you are not,” he says, “that is for sure what's happening with BECCS now.”

But people are researching it. Here's the idea:

As BECCS is usually conceived, bioenergy crops would be grown on unused agricultural land. In the Upper Missouri River Basin, that could mean conscripting fields set aside as part of the U.S. Department of Agriculture's Conservation Reserve Program (CRP), which pays farmers to leave fields fallow for environmental benefits. Given the right incentives, farmers could pull these lands back into production — something that has already happened in the region as demand for corn and soy have grown. “Farmers are no different than anyone else. We are profit-driven,” Flikkema says.

Here in Montana, farmers' bioenergy crop options are limited for now. Only a few adventurous growers like Flikkema are experimenting with canola and other oilseeds. As the climate warms, however, the entire region is projected to become more hospitable to plants such as switchgrass, a towering grass called Miscanthus, and vigorous poplar trees. These “second-generation” bioenergy crops are often seen as the future of bioenergy because, as perennials, they are far better at storing carbon in the soil and in their biomass than traditional fuel crops like corn and canola. They can also grow on marginal lands with less fertilizer and water, making it less likely they will compete with food production.

Once harvested, these crops would get ferried by truck or train to power plants and other industrial facilities where, along with waste from food crops and timber harvests, they would be burned for heat or electricity, or converted to ethanol and other liquid biofuels. The CO2 given off by either process would be siphoned off and compressed into a fluid. That concentrated CO2 would be piped away and pumped underground into porous rock formations, which abound in the Upper Missouri River Basin. Because of its long history of oil and gas production, the area is perforated with wells. Lee Spangler, an MSU chemist involved with the project, is studying whether any of the 11,000 wells near the Colstrip Power Plant in eastern Montana, for instance, would be good conduits for injecting carbon underground. The final result? Carbon is transferred from the atmosphere back to the geologic reservoirs from which it came.

BECCS isn't the only route to negative emissions. But alternative approaches, like capturing CO2 directly from the air using chemical reactions or absorbing it with ground-up minerals added to soils, are just beginning to see their first real-world tests. These techniques could one day surpass BECCS, but for now, they cost more, Vaughan says. “BECCS will pay for itself to some extent because it generates energy.”

BECCS isn't a total technological reach, either; its two components— bioenergy and carbon capture and storage, or CCS — are already happening to some degree today. Power plants around the world are burning biomass for energy, either alone or together with fossil fuels. CCS has been slow to take off, but dozens of projects are underway, including numerous pilots in the Great Plains, many of which pump CO2 from fossil fuel power plants into dwindling wells to drive out residual oil. One of the longest-running operations is in the North Sea, where the Norwegian oil company Statoil has been separating CO2 from natural gas and sequestering it underground for more than 2 decades.

To put the brakes on climate change, however, these tools would have to be deployed on an entirely unproven scale.

The whole article is good; it's not just about the problems of BECCS, but also about how it could work! The article is here:

• Julia Porter, The carbon harvest, Science, 16 February 2018, http://www.sciencemag.org/news/2018/02/vast-bioenergy-plantations-could-stave-climate-change-and-radically-reshape-planet

#savetheplanet
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"Set your phasers to thrill"
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