TIME Environment

Climate Change Could Happen Slower for the Next Decade, Study Says

California's Drought Becomes Critical
One of two major water storage lakes on the Russian River is lake Mendocino, which is nearly empty on January 24, 2014, near Ukiah, California. George Rose—Getty Images

Atmospheric temperatures are expected to rise slowly in the next decade

Temperatures have risen more slowly in the past decade than in the previous 50 years and will continue to rise at a somewhat slower rate in the next decade, according to a new study, even as climate change continues to raise temperatures to unprecedented levels worldwide.

The study, published in the journal Science, explained the temporary slowdown in rising temperatures as a potential consequence of the end of a 30-year current cycle in the Atlantic Ocean that pushes heat into the ocean.

“In the 21st century, surface warming slowed as more heat moved into deeper oceans,” the study says.

Despite this brief respite, the study says temperatures will begin to rise more quickly after the cycle is complete.

“Each of the last three decades has been successively warmer at the Earth’s surface than any preceding decade since 1850,” according to a different study published by the Intergovernmental Panel on Climate Change.

“Trends based on short records are very sensitive to the beginning and end dates and do not in general reflect long-term climate trends,” the IPCC study said, cautioning that the slowdown in global warming does not mean the atmosphere will not continue to heat at a faster rate.

TIME space

Evidence of Absolutely Enormous Dead Stars Discovered

Astronomers have a pretty good idea about what the first stars in the universe must have looked like. Theorists say they should have been gigantic, weighing in at anywhere from 20 times the mass of the Sun all the way up to 100 Suns’ worth of material or more. These giants would have burned far hotter than our own star, and far faster as well. The Sun, for example will live for about 10 billion years (it’s about half that old now), but the first stars should have torn through their fuel supply in just a few million years before blowing themselves apart in gigantic explosions.

Unfortunately, it all happened more than 13 billion years ago, and while powerful new instruments like NASA’s partially built James Webb Space Telescope might one day be able to to pick out the light of these mammoth stars, still streaming faintly across the universe after all that time, there’s no way at present to image them directly.

But a team of observers is now reporting in Science that they’ve picked up the telltale signature of the most massive of those first stars. “They’ve been predicted for years, but never seen before,” says Timothy Beers, of Notre Dame, one of the report’s co-authors. To be precise, they still haven’t seen the stars themselves; instead, the astronomers detected their chemical signatures, imprinted on a second generation of stars born just a bit later. Because they’re trying to understand a long-lost era of cosmic history indirectly, Beers and his colleagues call their field “stellar archaeology,”

Those second-generation stars were for more modest in terms of size and temperature and much slower-burning, which has allowed some of them to survive right up to the present. That includes SDSS J0018-0939, the star described in the new Science paper. It’s somewhat less massive than the Sun, and it’s relatively deficient in elements heavier than hydrogen and helium.

That’s a clue that it was formed early in the life of the universe.

Right after the Big Bang, those heavier elements, including everything from oxygen to carbon to silicon to iron, didn’t even exist; they were created in the nuclear furnaces at the cores of stars (which means that the calcium in your bones and the carbohydrates in your breakfast cereal were manufactured inside a star, long ago). For historical reasons, astronomers call any elements heavier than helium “metals” (carbon and nitrogen count as metals in astronomical jargon.)

Those “metals” were spread far and wide when the original stars exploded and incorporated into new stars, and since stars have been forming and exploding for billions of years now, those that formed relatively recently, such as the Sun, are relatively metal-rich. “Our Sun,” says Beers, “is a is a bucket into which the entire history of chemical evolution was poured.”

Stars that formed early on, by contrast, when there was still mostly just hydrogen and helium to be had, are metal-poor. SDSS J0018-0939 is one of them—but given its metal-poor status, it has a surprisingly large amount of iron. And given what theorists know about star formation and evolution, the only place it could have come from so early in the lifetime of the universe was the core of a gigantic star.

The evidence that such stars really did exist is still circumstantial, but that’s a lot better than being purely theoretical. It also adds to a growing understanding of what the universe must have looked like when the stars first turned on. Earlier efforts at stellar archaeology had yielded circumstantial evidence of much smaller (but still huge) first-generation stars, which were unusually rich in carbon rather than iron.

But to understand how the modern universe began to take shape, and how the galaxies came form out of the diffuse gases that dominated the earliest years of the cosmos, astronomers need to know the range of sizes those first stars came in—because how they lived and how they died set the stage for what would come afterward.

“It’s a complicated story,” says Beers, “but it’s incredibly interesting. You’re talking objects that exploded 13 billion years ago. I find it remarkable,” he admits, “that the question can be addressed at all.”

 

 

TIME Environment

Juvenile Coral and Fish Know When a Reef Has Gone Bad

World Without Corals
In this June 5, 2008 photo, fish gather on a coral reef in the Dry Tortugas National Park in Dry Tortugas, Fla. Numerous studies predict corals are headed toward extinction worldwide, some 50 percent of the Caribbean's corals are already dead, largely because of climate change, overfishing and pollution. Wilfredo Lee—ASSOCIATED PRESS

Too much seaweed and they're out of there

Baby coral and fish in the Pacific are able to detect both good and bad reefs, according to a Fiji-based study reported by the BBC. The study found that sea animals avoid reefs that do not give off the right chemical signals, because the failure to do so indicates that a reef is degraded.

According to the research, published in Science, when young coral and fish are presented with water samples taken from healthy reefs, and from reefs in overfished areas that are choked with seaweed, the sea creatures overwhelmingly choose the former.

Scientists say this could be a sign that simply designating a marine area as a protected zone may not be enough to help damaged reefs recover. The seaweed that has sprung up there may have to be removed as well.

“If you’re setting up a marine protected area to seed recruitment into a degraded habitat, that recruitment may not happen if young fish and coral are not recognizing the degraded area as habitat,” said Danielle Dixson of the Georgia Institute of Technology, the study’s prime author.

Once seaweed is removed, then damaged areas may start to see improvements, the BBC reports.

[BBC]

TIME Environment

Check Out the Freezing Cold Place Where Scientists Found Life

There are close to 4,000 organisms living in the lake, which hasn’t seen sunlight for millions of years

+ READ ARTICLE

A subglacial lake 800 meters beneath the West Antarctic ice sheet has been discovered to contain “viable microbial ecosystems,” according to the National Science Foundation, which funded the project. The findings are the result of a 2013 drilling expedition in which researchers used a sterile, hot water drill to reach and collect samples from Lake Whillans, in the west part of the continent.

Researchers for project Whillans Ice Stream Subglacial Access Research Drilling (WISSARD) found organisms that feed off of rocks for energy and use Carbon Dioxide as a carbon source in water and sediment samples from the lake.

TIME psychology

Quiz: Are You A Narcissist?

Take the Narcissistic Personality Inventory, developed by Robert Raskin and Howard Terry.

Check the answer in each pair that comes closest to describing you. Don’t leave any pairs blank; try to complete the survey in just a few minutes. The highest possible score is 40, the lowest is 0.

Penguin Group

Excerpted from The Narcissist Next Door: Understanding the Monster in Your Family, in Your Office, in Your Bed—in Your World

Read More: The Evolution of a Narcissist

TIME Environment

Scientists Discover Microbes in a Subglacial Antarctic Lake

Ice floes floating on water
Ice floating in Ross Sea, Antarctica on June 15, 2014. De Agostini—Getty Images

It could help point to the possibilities of life on other planets

The frozen desert of Antarctica is challenging enough for life — never mind conditions beneath that ice-bound mass. But NBC News reports that a recent discovery by scientists reveals the water beneath the West Antarctic Ice Sheet to be swarming with microbes.

The findings, published in Nature, reveal that a diverse microbe ecosystem of 4,000 distinct species exists in subglacial Lake Whillans, which lies beneath 800 m of ice. The chemoautotrophs — organisms that gain sustenance from minerals found in the water instead of from sunlight — could also hint to the possibility of life on other planets, National Geographic reports. Scientists say that the conditions that the microbes live in could be similar to those in frozen lakes found on Europa or Enceladus, Jupiter’s and Saturn’s moons respectively.

“The report is a landmark for the polar sciences,” Martyn Tranter, a professor at the University of Bristol (who was not involved in the study), wrote in a commentary in Nature.

Tranter added that the discovery also raised “the question of whether microbes could eat rock beneath ice sheets on extraterrestrial bodies such as Mars.”

The researchers will continue to survey Lake Whillan next winter in search of other organisms that could further point to the varying possibilities of life.

TIME Research

Humans and Neanderthals Were Actually Neighbors

Paleontologists know plenty about our nearest human cousins, the Neanderthals. They know that this highly successful species walked the Earth for some 300,000 years (we’ve been around for less than 200,000). They know the Neanderthals kept their caves surprisingly tidy; that they ate things other than raw meat; that they practiced recycling, wore jewelry and were generally much more sophisticated than their popular reputation would suggest.

Yet it didn’t take long after our own species invaded their last known outpost in Europe that the Neanderthals went utterly extinct. Now a new paper in Nature suggests it happened over a period of between 2,600 and 5,400 years or so—which is twice as fast as anyone had thought. The two groups did, evidently, coexist: “They lived in Europe at the same time,” says lead author Tom Higham, of Oxford, “although they were spatially separated. It was like a mosaic.” Agrees William Davies, of the University of Southampton, who wrote a commentary on the new research, also in Nature, “It’s not a neat story. It’s quite complex.”

The key to the new analysis was an unusually large sample of human and Neanderthal remains from 40 different sites across Europe, along with improved methods for filtering out contaminants from the samples before attempting to date them. In many cases, the remains weren’t bones but rather stone tools thought to characteristic of one species or the other—so-called Mousterian and Châtelperronian tools for the Neanderthals and Uluzzian tools for our own ancestors.

That raises, if not a red flag, then at least a sort of pinkish one, according to Davies. “In the old days, we had very few assemblages of tools, so it was quite easy to say that Mousterian tools represented Neanderthals, while tools with longer blades reflect anatomically modern humans.” But with more and more tools in their collections, paleontologists have become less sure. “The whole thing has become more blurred and less certain.”

The new analysis doesn’t depend entirely on who made what tools, however, and, says Davies, “the areas they’ve chosen to analyze are places where we can be more confident than most.” What makes the work so potentially important, he says, is that it gives a much finer-grained picture than ever before of where Neanderthals and modern humans lived and when, and how those patterns changed as Neanderthal numbers dwindled, then vanished.

That in turn will help anthropologists figure out how the Neanderthals vanished—what force or forces drove them extinct by about 40,000 years ago. “We think the Neanderthals had very low population numbers when modern humans arrived,” says Higham, perhaps in part because Europe was in the throes of an Ice Age at the time, so they were struggling against harsh conditions that couldn’t support large numbers of individuals. Modern humans, Higham observes, had been living in Africa, which was much more benign. “Modern humans also seemed to have more modern technology,” he says, “which wouldn’t have been a huge advantage, but over the long duration might have given them an edge.”

Scientists also know that Neanderthals and modern humans interbred at some level, which is why about 2% of our genes, on average, are Neanderthal in origin. The details of those interactions are still completely unknown—for now, anyway. “For me,” says Davies, “the big achievement here is that we now have a way of getting much more information out of both skeletal and archaeological remains. We can look at the molecular level on genetic inheritance, movement patterns, even what they were eating.”

The mystery of when and where the Neanderthals made their last stand may be just about wrapped up. And the answer to why they disappeared might not be a mystery for much longer.

 

TIME weather

Flash Floods and Stranded Drivers in Arizona After Heavy Rain

Fast and furious rainfall in the Phoenix area damaged houses, stranded drivers and forced at least one airborne rescue, which was broadcast live on television Tuesday. The Associated Press reported nearly 3,000 homes were left without power by the storm, which dumped up to two inches of rain in the span of an hour, in a state unused to so much precipitation

TIME Chemistry

Octopus Skin Has Inspired a New Type of Camouflage Sheet

It can only switch from black to transparent and back again, but that's a start

Scientists have developed a color-changing device inspired by octopuses and their natural camouflaging techniques.

The research, carried out at the University of Houston and University of Illinois at Urbana–Champaign, looked at how the skins of octopuses, squid and cuttlefish can change color so rapidly. From there, researchers were able to design a heat-sensitive sheet that quickly changes color when detecting light.

At room temperature the flexible sheet is black. Once the device’s top layer, which contains a heat-sensitive dye, detects light it becomes transparent. True, this is hardly a rainbow of hues, but scientists believe it is the first step to developing a camouflage material for human use.

“[The device] is by no means a deployable camouflage system but it’s a pretty good starting point,” said a lead researcher, John Rogers of the University of Illinois at Urbana–Champaign, to National Geographic.

Popular Mechanics broke down the layers of the new device as follows:

The top layer of the new device is loaded with a temperature-sensitive dye that appears black at low temperatures and clear at temps above 116 degrees F. This dye-filled layer sits on top of a layer of white reflective silver tiles, an ultra-thin layer of silicon circuits that control the dye’s temperature, and a transparent silicone rubber foundation. All together, this stack measures less than 200 microns thick. (The average human hair is 100 microns wide.)

Underneath this flexible sandwich is a base layer containing an array of light-sensing photodetectors. The corners of each dye-filled pixel and silver tile above this photoreceptor layer are notched, creating gaps that are like holes in a mask, allowing light to get through to the photoreceptors so they know how and when to change color. This adaptive camouflage system can respond to changing patterns of illumination within just one to two seconds.

[National Geographic]

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