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Scientists Have Finally Figured Out Why The Amazon River Runs Backward

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The Amazon once flowed in the opposite direction, from east to west. Reversing the direction of the Earth's largest river is no trivial thing, and geologists have pondered the cause for some time. In Earth and Planetary Science Letters The University of Sao Paulo's Dr Victor Sacek has demonstrated that nothing more than erosion is needed to explain this enormous shift.

With the mighty Andes at the western end of the continent it seems logical that South America's rivers flow east. While the Amazon discharges five times as much water as any other river on the planet, The Orinoco and the Rio de la Plata run the same way, each dwarfing any river in North America or Europe in the process.

However, until 10 million years ago, most of what is now the Amazon basin was drained by a river that flowed west into a giant lake that lay at the feet of the northern Andes. From there the water flowed north to the Caribbean Sea. Since the Isthmus of Panama had yet to form, this water was then swept west into the Pacific.

To tilt an entire continent seems such a vast endeavor that geologists had speculated changes in convection within the Earth's mantle, perhaps resulting from the break-up of Africa and South America, must have driven this.

Sacek, on the other hand, shows that the rise of the Andes as the South American plate rode over the Nazca Plate can explain the process on the appropriate timescale. Sacek included in his model the fact that as the mountains rose they intercepted more rain-bearing clouds, which in turn triggered more erosion.

At first the Andes rise produced a trough to the east, which became the paleolake into which the westward-flowing Amazon emptied. With time, however, this sinking slowed and erosion accelerated, replacing the lake with a series of wetlands known as the Pebas. The vast Pebas marshlands would have been an ecosystem like nothing we see today, but eventually sediment accumulation raised the region to the point where the rainfall in the area was pushed back the other way.

The model successfully matches the observation that sediment deposited at the Amazon's mouth has increased over the period of its eastward flow. At first, when the Amazon's sources were relatively flat, much of the sediment was dumped part way to its mouth, only being remobilized eons later.

Sacek admits however, that his model "Fails to fully reproduce the spacial and temporal evolution of the Pebas system as observed in geological data" and says further work is needed.

H/T Science

SEE ALSO: Scientists Have Figured Out An Age-Old Mystery About Rivers

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This Photographer Captures The Incredible Human Side Of Animals

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Tim Flach

British photographer Tim Flach is known for taking human-like portraits of animals. "More Than Human," his latest award-winning body of work, captures the emotions of wild creatures through intensely close shots — like the stunning picture of a gorilla on the right.

The intimate animal portraits, which feature everything from a forlorn-looking lion to a chimpanzee cradling its child, are meant to illuminate the similarities between animal poses, gestures, and gazes, and our own.

He looks at the way we assign human emotions and thoughts to animals, even though we don't know what they think or feel.

"What underlines my work in this project are the questions about how we shape nature and how it shapes us," Flach writes on his website.

Photographing animals on a set, as opposed to in their natural habitat comes with a unique set of challenges.

"You can never predict an animal's mood," Flach says. "So you have to plan beforehand to get what you want." To make the animals feel as comfortable as possible, Flach may adjust the temperature of the studio or play music.

You can purchase a hardcover copy of Flach's animal portraits here or visit his website to see more of the award-winning photographer's work.

A featherless chicken "dances" in front of the camera.



An elephant sprays water from its trunk.



A tiger furiously shakes its head after being doused with water.



See the rest of the story at Business Insider

Here's What Would Happen To Earth After A Nuclear War

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Operation TeapotYou've seen what a nuclear winter looks like, as imagined by filmmakers and novelists. Now you can take a look at what scientists have to say.

In a
new study, a team of four U.S. atmospheric and environmental scientists modeled what would happen after a "limited, regional nuclear war."

To inexpert ears, the consequences sound pretty subtle—two or three degrees of global cooling, a nine percent reduction in yearly rainfall.

Still, such changes could be enough to trigger crop failures and famines. After all, these would be cooler temperatures than the Earth has seen in 1,000 years.

Let's take a detailed look at some of these super-fun conclusions, shall we?

First, what happened?

The team imagines 100 nuclear warheads, each about the size of the atomic bomb the U.S. dropped on Hiroshima, detonate over the Indian subcontinent. The team members are imagining an India-Pakistan nuclear war. It seems unfair to single out these nations, but I guess they're the poster children because they have relatively small nuclear stockpiles compared to countries such as the U.S., Russia and China. The idea is, If these lightweights can do this to Earth, imagine what the bigwigs can do.

After the Indian-Pakistani nuclear exchange…

  • Five megatons of black carbon enter the atmosphere immediately. Black carbon comes from burned stuff and it absorbs heat from the sun before it can reach the Earth. Some black carbon does eventually falls back to Earth in rain.

  • After one year, the average surface temperature of the Earth falls by 1.1 kelvin, or about two degrees Fahrenheit. After five years, the Earth is, on average, three degrees colder than it used to be. Twenty years on, our home planet warms again to about one degree cooler than the average before the nuclear war.

  • Earth's falling temperatures reduces the amount of rain the planet receives. Year five after the war, Earth will have 9 percent less rain than usual. Year 26 after the war, Earth gets 4.5 percent less rain than before the war.

  • In years 2-6 after the war, the frost-free growing season for crops is shortened by 10 to 40 days, depending on the region.

  • Chemical reactions in the atmosphere eat away Earth's ozone layer, which protects Earth's inhabitants from ultraviolet radiation. In the five years after the war, the ozone is 20 to 25 percent thinner, on average. Ten years on, the ozone layer has recovered so that it's now 8 percent thinner.

  • The decreased UV protection may lead to more sunburns and skin cancers in people, as well as reduced plant growth and destabilized DNA in crops such as corn.

  • In a separate study, published in 2013, International Physicians for the Prevention of Nuclear War estimated 2 billion people would starve in the wake of a 100-A-bomb war.

Okay, I know I've just made your day with this list. Still, there's a point to all this doom and gloom, the modelers write in their paper. The scientists want to motivate countries to destroy the estimated 17,000 nuclear weapons they still hold.

Will this work? Well, scientists and artists have been imagining the dire consequences of an atom-bomb war for decades. The very idea of a "nuclear winter" entered the popular imagination in 1983, when a study, authored by a team including Carl Sagan, first proposed that soot from fires after a nuclear war would block sunlight from reaching Earth.

Twenty-five years later, environmental scientists began using modern climate models to figure out what might happen after a nuclear war. Yep, these are the same models that scientists use to predict the effects of human-driven global warming. This new paper combined a number of those state-of-the-art models. If you check out the paper, published in the journal Earth's Future, you can see how these conclusions compare to previous climate-model-based calculations. Different modeling efforts have come up with slightly different years for when the Earth would be coldest after a nuclear war, for example, but they generally agree that the effects would be, well, severe and long-term.

This article originally appeared on Popular Science

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SEE ALSO: Five Ways Nuclear War Could Still Happen

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Scientists Finally Got A Close-Up View Of That Mysterious Siberian Crater — Here's What They Found

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Russia Siberia Crater Yamal

When a helicopter discovered a mysterious giant crater on the Yamal Peninsula of Siberia, a place referred to as "the end of the world," speculation was rampant. People suggested it could have been caused by a meteorite, an underground explosion related to nearby natural gas fields, or even something more ominous or extra-terrestrial.

The crater looks almost too incredible to be real, but researchers finally made their way there on July 16 and it most certainly is the real thing. But even though the expedition revealed more information, the exact cause of the crater is still being determined.

Here's what it looks like from a helicopter:

siber crater gif

Some think the crater might have been formed by a "pingo" a geological feature found in areas with permafrost like the Yamal Peninsula.

A pingo is a hill or dome that forms in the permafrost because of an underground ice formation, caused by groundwater forcing its way up towards the surface. There it encounters colder temperatures and freezes. If it melted, due to warming temperatures, it could have left a crater behind.

Another possibility is that as the ground warms, an underground ice formation may have released gas that had been trapped there for thousands of years, which could have forced its way through the surface, bursting out and leaving a giant hole.

Siberia Crater Yamal Russia"For now we can say for sure that under the influence of internal processes there was an ejection in the permafrost," Andrey Plekhanov, senior researcher at the State Scientific Centre of Arctic Research, told The Siberian Times. In other words, whatever happened caused pressure to build up underground, forcing the above layer of earth — permafrost — to break apart and fly outward from the center of the hole.

Anna Kurchatova from the Sub-Arctic Scientific Research Centre described the process to The Siberian Times as one where frozen gas, salt, and sand underground may have warmed enough to cause "an effect like the popping of a Champagne bottle cork."Russia Siberia CraterPlekhanov and other researchers have said that the crater was most likely caused by changing temperatures in the region — potentially related to global warming — though more research is needed to be certain. The Yamal Peninsula has experienced particularly warm summers recently, which could have caused the melting.

Russia Siberia CraterThe investigation revealed that the hole at the top of the crater has a diameter of approximately 100 feet, smaller than initial estimates of more than 600 feet., though it is tough to measure due to a somewhat oval shape. The crater is deep though — approximately 300 feet, and an icy lake sits at the bottom.

The research team said that ice in the sides of the crater is melting as it's exposed to the sun, causing water to flow down into the lake. This may eventually fill the crater.

Russia Siberia Crater From AboveAlthough researchers thought that at first they'd seen evidence of burning visible on the edges of the crater, the closer examination revealed no traces of a fiery explosion, which rules out a meteorite. Plekhanov also said that the crater isn't quite close enough to the gas fields, about 19 miles away, to have been caused by a gas pumping accident.

The Russian researchers are using satellite footage to see if they can determine when the crater appeared, though they imagine it happened in the past year or two.

Russia Siberia Crater

Plekhanov said that the phenomenon seems natural, though still incredibly strange. He told The Siberian Times, "I've never seen anything like this, even though I have been to Yamal many times."

Here's the original video footage that revealed the crater to the world.

SEE ALSO: Ancient Giant Viruses Revived After 30,000 Years In Siberian Permafrost

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Here's How Much Your Diet Of Choice Kills The Environment

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Greenhouse gas emissions from livestock production have increased by more than 50 percent over the past 50 years and are set to zoom higher as the developing world consumes more meat, finds a new study published in the journal Proceedings of the National Academy of Sciences (PNAS).

The research is based on analysis of the impacts of livestock production per calorie consumed, including water and fertilizer use, land area requirements, and other factors. It went beyond carbon dioxide, evaluating greenhouse gas emissions from methane and nitrous oxide.

Like other studies, the paper found that beef has overwhelmingly the biggest climate impact among dairy, poultry, pork, and eggs.

"Impacts of dairy, poultry, pork, and eggs were mutually comparable within a factor of two. Beef, however, required 28 times more land, 11 times more irrigation water, five times more greenhouse gas emissions, and six times more reactive nitrogen fertilizer than the respective average burdens of the other four livestock categories," stated a release from PNAS.

The study also noted a significant divergence in trends on livestock-related emissions between industrialized countries, where emissions peaked in the 1970s, and the developing world, where emissions could double by 2050.

"The developing world is getting better at reducing greenhouse emissions caused by each animal, but this improvement is not keeping up with the increasing demand for meat," said study co-author Dario Caro of the University of Siena in Italy. "As a result, greenhouse gas emissions from livestock keep going up and up in much of the developing world."

The study concludes that shifting protein consumption away from beef would help curb rising temperatures."Potato, wheat, and rice production, on average, required two to six times less resources per calorie consumed than non-beef livestock," said PNAS. "Understanding the impacts of different classes of livestock may empower consumers and policy-makers to mitigate environmental burdens through diet choice and agricultural policy."

"That tasty hamburger is the real culprit," added the Carnegie Institution's Ken Caldeira, who worked with Caro, but wasn't an author of the paper."It might be better for the environment if we all became vegetarians, but a lot of improvement could come from eating pork or chicken instead of beef."

CITATION: Gidon Eshel, Alon Shepon, Tamar Makov, and Ron Milo. Land, irrigation water, greenhouse gas, and reactive nitrogen burdens of meat, eggs, and dairy production in the United States. PNAS Online Early Edition the week of July 21-July 25, 2014

SEE ALSO: What Would Happen If Everyone In The World Gave Up Meat

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How Humans Have Changed In The Last 100 Years

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probiotic illustration twins fat skinny

Humans are getting taller; they're also fatter than ever and live longer than at any time in history. And all of these changes have occurred in the past 100 years, scientists say.

So is evolution via natural selection at play here? Not in the sense of actual genetic changes, as one century is not enough time for such changes to occur, according to researchers.

Most of the transformations that occur within such a short time period "are simply the developmental responses of organisms to changed conditions," such as differences in nutrition, food distribution, health care and hygiene practices, said Stephen Stearns, a professor of ecology and evolutionary biology at Yale University. [10 Things That Make Humans Special]

But the origin of these changes may be much deeper and more complex than that, said Stearns, pointing to a study finding that British soldiers have shot up in height in the past century.

"Evolution has shaped the developmental program that can respond flexibly to changes in the environment," Stearns said. "So when you look at that change the British army recruits went through over about a 100-year period, that was shaped by the evolutionary past."

And though it may seem that natural selection does not affect humans the way it did thousands of years ago, such evolutionary mechanisms still play a role in shaping humans as a species, Stearns said.

"A big take-home point of all current studies of human evolution is that culture, particularly in the form of medicine, but also in the form of urbanization and technological support, clean air and clean water, is changing selection pressures on humans," Stearns told Live Science.

"When you look at what happens when the Taliban denies the polio vaccination in Pakistan, that is actually exerting a selection pressure that is different in Pakistan than we have in New York City," he said.

Here's a look at some of the major changes to humans that have occurred in the past century or so.

(Some) people have grown taller

A recent British study, published by the Institute for the Study of Labor (IZA) in Bonn, Germany, showed that young men in the United Kingdom have grown by 4 inches (10 centimeters) since the turn of the 20th century.

In the study of British recruits, the average height of British men, who had an average age of 20, was about 5 feet 6 inches (168 centimeters) at the turn of the century, whereas now they stand on average at about 5 feet 10 inches (178 cm). The increase can be attributed, most likely, to improved nutrition, health services and hygiene, said the researchers from the University of Essex in Colchester.

In a number of other developed countries, people have been growing taller, too, reaching the world's current greatest average height of 6 foot 1 inch (1.85 meters) in the Netherlands. Interestingly, Americans were the tallest people in the world by World War II, measuring 5.8 feet (1.77 meters), but by the end of the 20th century, they fell behind, and the average U.S. height has stagnated, according to a study by John M. Komlos, currently a visiting professor of economics at Duke University. [Why Did Humans Grow 4 Inches in 100 Years?]

And even in some of those countries where the average height has been rising, the increase has not been uniform. For instance, people from former East Germany are still catching up height-wise with former West Germans after years of communist rule, said Barry Bogin, a professor of biological anthropology at Loughborough University in the United Kingdom. And in some non-Western countries that have been plagued by war, disease and other serious problems, average height has decreased at one point in time or another. For instance, there was a decline in the mean height among blacks in South Africa between the end of the 19th century and 1970, Bogin wrote in one of his studies, published in the Nestle Nutrition Institute workshop series in 2013. He explained that the decline was likely related to the worsening of socio-economic conditions before and during apartheid.

"It shows you the power and the generation-after-generation effects of something bad that happened to your mother gets carried on to you and your children, and it takes about five generations to overcome just one generation of starvation, or epidemic illness, or something like that," Bogin told Live Science.

Unfortunately for those individuals, height seems to improve humans' quality of life and chances of survival. For instance, in the United States, taller people make more money on average, as they are perceived as "more intelligent and powerful," according to one such study published in 2009 in the Economic Record.

Everyone is getting fat

Since the 1970s, Bogin has been studying growth patterns of Maya children and their families living in Guatemala, Mexico, and the United States. When Maya people move to the United States, their kids born here are 4.5 inches (11.4 centimeters) taller than siblings born in Mexico or Guatemala. This likely results from the accessibility of more-nutritious food in the United States, for instance, through lunch programs at schools, as well as better health care, Bogin noted. The Maya kids are also less exposed to infectious diseases, which are less common in the United States than in the countries of the parents' origin. [7 Devastating Infectious Diseases Explained]

But this increase in height comes with a high price tag.

"Not only do these Maya kids begin to look more like Americans in height, but they become even super-Americanized in their weight, by becoming overweight," Bogin told Live Science.

"People are getting fatter everywhere in the world," he said. (In 2013, 29 percent of the world's population was considered overweight or obese, according to a study published May 29 in the journal The Lancet.)

Exactly why humans are getting fatter is currently a question of heated scientific debate. Some researchers point to the traditional argument of eating too much and exercising too little as the culprit, whereas others offer alternative explanations, including the role of genetics and viruses that have been linked to obesity. The issue of excessive weight and obesity gets even more complicated, as many studies have linked being fat with poverty, which goes against a popular association of obesity and wealth.

Interestingly, the Maya kids in Indiantown, Florida, on whom Bogin focused his studies, had the highest rates of being overweight and obese of all ethnic and racial groups in the area, including Mexican-Americans, African-Americans, Haitians and European-Americans. This may have something to do with epigenetics, or heritable changes that turn genes on and off but that are not caused by changes in the DNA sequence. For instance, the environment may have caused epigenetic changes to some ethnic groups that affect how the body stores excessive energy from food, Bogin said.

"There may be an expectation that since your mother suffered and your grandmother suffered, somehow this suffering gets passed on to the current generation of children, and they kind of expect that there is going to be bad times and there is not going to be enough food," he said. "So when there are good times, eat as much as you can, and the body should preferentially store the extra energy as fat."

This mechanism of fat storage driven by a history of malnutrition or starvation may be occurring in other poor populations in the world who are becoming overweight and obese, he said.

Earlier puberty

In many countries, children mature earlier these days. The age of menarche in the United States fell about 0.3 years per decade from the mid-1800s (when girls had their first menstrual period, on average, at age 17) until the 1960s, according to a 2003 study in the journal Endocrine Reviews, which also suggested better nutrition, health and economic conditions often play roles in lowering the age of menarche. Today the average age of menarche in U.S. girls is about 12.8 to 12.9 years, according to Bogin. The onset of puberty, however, is defined as the time when a girl's breasts start to develop. In the United States, it is 9.7 years for white girls, 8.8 years for black girls, 9.3 years for Hispanic girls and 9.7 years for Asian girls.

Studies have also pointed to a link between obesity and early puberty, as girls with higher body mass indexes (BMIs) are generally more likely to reach puberty at younger ages.

"The influence of BMI on the age of puberty is now greater than the impact of race and ethnicity," Dr. Frank Biro, a professor of pediatrics at Cincinnati Children's Hospital in Ohio, told Live Science in a 2013 interview.

And earlier puberty may have long-term health consequences, Biro said. For instance, studies have suggested that girls who mature earlier are more likely than those who mature later to develop high blood pressure and type 2 diabetes later in life.

There are also social consequences of earlier puberty; in some cultures, when a girl is biologically mature, she is also considered mature enough for marriage, Bogin noted. This may mean that she will not be able to continue her education or have a career once she does get married.

Therefore, the later a girl gets her first period, the better for her overall educational and life prospects. In fact, a Harvard study published in 2008 in the Journal of Political Economy showed that, in rural Bangladesh, where 70 percent of marriages occur within two years of menarche, each year that marriage is delayed corresponds to 0.22 additional year in school and 5.6 percent higher literacy.

Longevity and its bittersweet consequences

Humans are now living longer than ever, with average life expectancy across the globe shooting up from about 30 years old or so during the 20th century to about 70 years in 2012, according to the World Health Organization. The WHO predicts global life expectancy for women born in 2030 in places like the United States to soar to 85 years. The boost in life expectancy could be linked to significant advances in medicine, better sanitation and access to clean water, according to Bogin.

Although all of these factors have also greatly reduced mortality rates from infectious diseases, the deaths from degenerative diseases such as Alzheimer's, heart disease and cancer have been on the rise, Stearns said. In other words, people are living longer and are dying from different diseases than they did in the past.

"An American baby born in the year 2000 can expect to live 77 years and will most likely die from cardiovascular disease or cancer," Bogin said. [The Top 10 Leading Causes of Death]

As is often the case with biological advantages that humans sometimes gain, old age also comes with trade-offs.

"As more of us live longer, then more and more of us are encountering a death which is protracted and undignified," Stearns said. "So there are costs to all of this wonderful advance."

Autoimmune diseases such as multiples sclerosis and type I diabetes have also become more common, according to Stearns. Some scientists think the surge in such diseases is related to improved hygiene— the same factor that has allowed people to get rid of many infectious diseases, said Joel Weinstock, chief of gastroenterology at Tufts University Medical Center in Massachusetts. When the body is not exposed to any, or very few, germs, the immune system can overreact to even benign bugs, the thinking goes.

"Our theory is that when we moved to this super-hygiene environment, which only occurred in the last 50 to 100 years, this led to immune disregulation," Weinstock told Live Science in a 2009 interview. "We're not saying that sanitation is not a good thing — we don't want people to jog up to riverbanks and get indiscriminately contaminated. But we might want to better understand what factors in hygiene are healthy and what are probably detrimental, to establish a new balance and hopefully have the best of both worlds."

What is next for the human species?

It is hard so say what is in store for humans, as technology is changing the world so quickly.

"There is some fear out there that an esoteric cabal of scientists in white coats is going to take over the future of evolution with genetic engineering," Stearns said. "Whether we want to or not, we have already changed our future course of evolution, and it is not being done by some small group of people who are thinking carefully and planning, it is being done as a byproduct of thousands of daily decisions that are implemented with technology and culture."

"And we don't really know where that is going," he said, adding that, "once you accept that culture [including medicine, technology, media and transportation] has become a really strong driving force in human evolution, that is — we don't know how to predict culture."

Copyright 2014 LiveScience, a TechMediaNetwork company. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.

SEE ALSO: Humans May One Day Have Pig Hearts

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Farmers Take Drastic Measures To Contain Explosion Of 'Superweeds'

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weeds farmer roundup superweed(Reuters) - Farmers in important crop-growing states should consider the environmentally unfriendly practice of deeply tilling fields to fight a growing problem with invasive "superweeds" that resist herbicides and choke crop yields, agricultural experts said this week.

Resistance to glyphosate, the main ingredient in widely used Roundup herbicide, has reached the point that row crop farmers in the Midwest are struggling to contain an array of weeds, agronomists say.

Extreme controls are needed to fight herbicide-resistant weeds in some areas, University of Missouri weed scientist Kevin Bradley said in a report to farmers. One particularly aggressive weed that can grow 1-2 inches a day is Palmer amaranth.

“Palmer amaranth is our No. 1 weed to watch in Missouri and the Midwest right now,” Bradley said.

He said farmers facing extreme out-of-control weeds should try deep tillage, a practice that removes weeds but can also lead to soil erosion and other environmental concerns.

Farmers moved away from heavy tillage of the land decades ago, and the more sustainable 'no-till' farming has become the norm. But it relies on heavy use of herbicides like glyphosate, and the U.S. Department of Agriculture says 70 million acres of U.S. farmland had glyphosate resistant weeds in 2013.

Palmer amaranth is also "exploding" across Kansas this year, according to Dallas Peterson, a weed specialist with Kansas State University. “We have had numerous calls about poor control of Palmer amaranth with glyphosate this year,” he said.

Weed resistance has grown as farmers have increased their use of glyphosate in conjunction with the Monsanto Co's introduction of an array of crops genetically altered to tolerate the herbicide.

 

 

(Reporting by Carey Gillam; Editing by Dan Grebler)

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Climate Change Deniers’ Argument That Ice Growth In The Antarctic Is Accelerating Came From A Data Error

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Antarctica Sea Ice Ross Sea

The amount of the earth's ocean surface covered by sea ice has been continually observed by satellites and its extent estimated since 1978. The trend has been for shrinking sea ice in the Arctic and, more recently, expanding sea ice in the Antarctic.

This somewhat counter-intuitive finding has been explained by reference to the ozone hole, currents, and winds. But it seems in part it has a more straightforward origin, stemming from an error in how the data is recorded and processed.

Several mathematical algorithms have been developed to convert raw satellite data into estimates of the area covered by at least some sea ice. While for the most part the results of different algorithms are in reasonable agreement, there are differences. A widely used method is the Bootstrap algorithm, developed at NASA Goddard, which performs particularly well at estimating Antarctic sea ice compared to others.

As satellite sensors have only a limited lifespan, to calculate trends over longer time periods requires stitching together the records from several sensors. However, each sensor is a little bit different, and these differences need to be corrected to create a consistent record over several decades. Slight adjustments in the algorithms are made to ensure the estimates from the new sensor match as closely as possible to the estimates from the old sensor during the period when their records overlap. This can never be done perfectly, but with care disagreements can be minimised. All algorithms, including Bootstrap, do some form of inter-calibration to try to ensure the data is consistent.

The difference is the data

Bootstrap was used to report sea ice extent for the last two IPCC reports, AR4 in 2007 and AR5 in 2013. Between AR4 and AR5, Bootstrap changed from Version 1 to the improved Version 2. The reprocessed data set, V2, shows a magnified sea ice increase over V1. This wasn't noticed at the time because Antarctic trends, being relatively small in magnitude and with large year-to-year variations, could change fairly substantially from year to year in any case.

However, Ian Eisenman who led our investigation, published in the Cryosphere journal, found that the growth of Antarctic sea ice between the last set compiled with V1 and the first compiled with V2 was greater than could be explained just from adding more data. I helped find and provide the earlier V1 data and he and fellow co-author Joel Norris compared the two versions. We found the discrepancy can be pinned to a sensor calibration change in 1991.

ice measurement chart

Our analysis doesn't discern in which version the inter-calibration error occurred — we simply compared the two versions and noticed the jump. The data set producer, Joey Comiso, has now looked at the issue and is confident that the error lies in V1, meaning the current version in use and used in AR5 is correct. Ian, Joel, and I are interested in looking further into this to confirm the V1 error.

But the end result is the same

It's important to emphasise that this sort of reprocessing of climate data — any scientific data, in fact — is not just common, but part of the scientific process; better data becomes available, methods are improved, errors are found and corrected. Data sets are never perfect, but as scientists we continually work to improve our data and understanding of it in order to get closer and closer to the truth. I think this paper and the reprocessing of Bootstrap are good examples of this process.

Fundamentally the paper doesn't change our understanding of Antarctic sea ice. Today, regardless of which version of the data or sensor you use, Antarctic sea ice extent is increasing at a statistically significant rate. The paper documents that the jump in trend numbers reported between V1 and V2 was due to processing and not due to variation in sea ice extent. Our results simply correct the published literature and show that, contrary to what was previously thought, the increase in Antarctic sea ice hasn't accelerated in the past 15 years, but has been remained consistently positive at moderate levels. Unlike Arctic sea ice, and the Antarctic continental ice sheets, which have been consistently, and substantially, falling.


Next, read this: The Arctic melts, but oceans and ozone hole may cool Antarctica

The Conversation

Walt Meier does not work for, consult to, own shares in or receive funding from any company or organisation that would benefit from this article, and has no relevant affiliations.

This article was originally published on The Conversation. Read the original article.

SEE ALSO: These Maps Will Show You When The Hottest Day Of The Year Hits Your Town

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Why Birds Fly In A V-Formation

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bird formationBI Answers: Why do birds fly in a V?

Scientists have long held that birds fly in a V-formation to save energy. But it was only recently revealed how and why birds benefit from this trick.

Migratory birds flying in a "V" shape flap their wings at precise times to take advantage of the lifting power generated by the bird in front, British researchers, led by Steven Portugal at the Royal Veterinary College in London, reported earlier this year in Nature.

The study took advantage of new sensors that tracked the movements of 14 northern bald ibises during a portion of their migratory flight from Austria to Italy. This was the first time that data had been recorded from birds flying in the wild.

When a bird flaps its wings, it creates lift by generating a looping motion of air around the wing.

The airflow blowing over the top of the wing is thrown downward, known as downwash (shown in red in the graphic below), while the air at the wing's tips is accelerated upwards, known as upwash (shown in blue).

Bird FlyingThe birds want to be in the region of upward-moving air to reduce the effort needed to fly.

Birds not only position themselves in the best possible spots to take advantage of the upward flow of air. They are also paying attention to the timing of the flap movements of the bird ahead, "which create tip vortices that undulate up and down," Florian Muijres and Michael Dickinson wrote in a News & Views commentary on the study, also published in Nature.

A bird will alter the timing of its wing beat to stay in the upwash created by the moving wingtips of the bird ahead of it.

"A bird that is following another bird must carefully adjust its own flapping motion, not in perfect temporal synchrony with the leader, but rather at a precise phase lag that tracks the tip as it oscillates," Muijres and Dickinson write.

To do all those things, the best way for the birds to fly is in a V- shape.

Check out the video below for more on why birds fly in a V-formation.

This post is part of a continuing series that answers all of your "why" questions related to science. Have your own question? Email science@businessinsider.com with the subject line "Q&A"; tweet your question to @BI_Science; or post to our Facebook page.

SEE ALSO: Why You Should Never Refrigerate Tomatoes

Don't Miss: More BI Answers

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The 10 Most Expensive Weather Disasters In The Americas

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Oklahoma TornadoA new report released by the World Meteorological Organization catalogs the economic damage from extreme weather conditions all over the world.

The WMO survey looked at climate events from 1970 to 2012. Here are a couple graphics that sum up the economic cost to North America, Central America, and the Caribbean.

weather expensive climate map

Storms are the most common environmental disaster in North America, Central America, and the Caribbean. Out of the 1,631 disasters identified in the region between 1970 and 2012, storms accounted for 55 percent of them, according to the WMO. While they may be just over half of the disasters cataloged, storms accounted for 79 percent of the economic losses from climate events between 1970 and 2012. That's a whopping $796.72 billion.

It is important to note that all of the economic losses listed above are identified by the WMO as occurring in the United States. Essentially, the United States loses the most money when extreme climate events occur (WMO says this is mainly because there's more expensive things to damage than other regions in the area).

It's also interesting to note that Canada, for which the same logic could be applied, doesn't make an appearance in the top 10. Canada, it seems, has substantially fewer extreme weather events than the United States. Since 1970, the United States has dealt with 691 disasters, Canada has only had 93. Our neighbors to the north did suffer from some of the same storms we did, being pummeled by a few Nor'easters in 2013

But economic losses aren't the only way to measure the cost of an extreme climate event. When you rank disasters by reported deaths (instead of reported economic losses), a very different picture emerges, the United States is no longer the nation that suffers the most.  

expensive climate change 

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A Chinese River Just Turned 'As Crimson As Blood'

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On Thursday morning, a river in eastern China suddenly turned a bloody shade of red, according to unverified reports by ABC News, China News, Shanghaist, and others.

"Local residents say the river was running normally at 4am, but it started to redden at around 6am, and in no time turned as crimson as blood,"China Radio International reported.

Here are some incredible pictures that appear to show the crimson river.

While nobody is quite sure what caused the alarming change, the ABC report said "a paper manufacturer, a food-coloring company and a clothing-maker" were located along the river. When China's Jian River turned red in 2011, it was traced to a company that was illegally dumping red dye into the waterway. The Yangtze River had a similar incident, back in 2012, which was thought to have been caused by silt in the river.

ABC News notes that the Wenzhou Environmental Protection Bureau is investigating.

SEE ALSO: If You Think China's Air Is Bad, You Should See The Water

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Free Exchange: Sun, Wind and Drain

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solar powerWind and solar power are even more expensive than is commonly thought.

SUBSIDIES for renewable energy are one of the most contested areas of public policy. Billions are spent nursing the infant solar- and wind-power industries in the hope that they will one day undercut fossil fuels and drastically reduce the amount of carbon dioxide being put into the atmosphere.

The idea seems to be working. Photovoltaic panels have halved in price since 2008 and the capital cost of a solar-power plant--of which panels account for slightly under half--fell by 22% in 2010-13. In a few sunny places, solar power is providing electricity to the grid as cheaply as conventional coal- or gas-fired power plants.

But whereas the cost of a solar panel is easy to calculate, the cost of electricity is harder to assess. It depends not only on the fuel used, but also on the cost of capital (power plants take years to build and last for decades), how much of the time a plant operates, and whether it generates power at times of peak demand. 

To take account of all this, economists use "levelised costs"--the net present value of all costs (capital and operating) of a generating unit over its life cycle, divided by the number of megawatt-hours of electricity it is expected to supply.

The trouble, as Paul Joskow of the Massachusetts Institute of Technology has pointed out, is that levelised costs do not take account of the costs of intermittency. Wind power is not generated on a calm day, nor solar power at night, so conventional power plants must be kept on standby--but are not included in the levelised cost of renewables.

Electricity demand also varies during the day in ways that the supply from wind and solar generation may not match, so even if renewable forms of energy have the same levelised cost as conventional ones, the value of the power they produce may be lower. In short, levelised costs are poor at comparing different forms of power generation.

To get around that problem Charles Frank of the Brookings Institution, a think-tank, uses a cost-benefit analysis to rank various forms of energy. The costs include those of building and running power plants, and those associated with particular technologies, such as balancing the electricity system when wind or solar plants go offline or disposing of spent nuclear-fuel rods.

The benefits of renewable energy include the value of the fuel that would have been used if coal- or gas-fired plants had produced the same amount of electricity and the amount of carbon-dioxide emissions that they avoid. 

Mr Frank took four sorts of zero-carbon energy (solar, wind, hydroelectric and nuclear), plus a low-carbon sort (an especially efficient type of gas-burning plant), and compared them with various sorts of conventional power. Obviously, low- and no-carbon power plants do not avoid emissions when they are not working, though they do incur some costs.

So nuclear-power plants, which run at about 90% of capacity, avoid almost four times as much CO{-2} per unit of capacity as do wind turbines, which run at about 25%; they avoid six times as much as solar arrays do. If you assume a carbon price of $50 a tonne--way over most actual prices--nuclear energy avoids over $400,000-worth of carbon emissions per megawatt (MW) of capacity, compared with only $69,500 for solar and $107,000 for wind.

Nuclear power plants, however, are vastly expensive. A new plant at Hinkley Point, in south-west England, for example, is likely to cost at least $27 billion. They are also uninsurable commercially. Yet the fact that they run around the clock makes them only 75% more expensive to build and run per MW of capacity than a solar-power plant, Mr Frank reckons.

To determine the overall cost or benefit, though, the cost of the fossil-fuel plants that have to be kept hanging around for the times when solar and wind plants stand idle must also be factored in. Mr Frank calls these "avoided capacity costs"--costs that would not have been incurred had the green-energy plants not been built.

Thus a 1MW wind farm running at about 25% of capacity can replace only about 0.23MW of a coal plant running at 90% of capacity. Solar farms run at only about 15% of capacity, so they can replace even less. Seven solar plants or four wind farms would thus be needed to produce the same amount of electricity over time as a similar-sized coal-fired plant. And all that extra solar and wind capacity is expensive.

A levelised playing field

If all the costs and benefits are totted up using Mr Frank's calculation, solar power is by far the most expensive way of reducing carbon emissions. It costs $189,000 to replace 1MW per year of power from coal. Wind is the next most expensive. Hydropower provides a modest net benefit.

But the most cost-effective zero-emission technology is nuclear power. The pattern is similar if 1MW of gas-fired capacity is displaced instead of coal. And all this assumes a carbon price of $50 a tonne. Using actual carbon prices (below $10 in Europe) makes solar and wind look even worse. The carbon price would have to rise to $185 a tonne before solar power shows a net benefit.

There are, of course, all sorts of reasons to choose one form of energy over another, including emissions of pollutants other than CO{-2} and fear of nuclear accidents. Mr Frank does not look at these. Still, his findings have profound policy implications. At the moment, most rich countries and China subsidise solar and wind power to help stem climate change.

Yet this is the most expensive way of reducing greenhouse-gas emissions. Meanwhile Germany and Japan, among others, are mothballing nuclear plants, which (in terms of carbon abatement) are cheaper. The implication of Mr Frank's research is clear: governments should target emissions reductions from any source rather than focus on boosting certain kinds of renewable energy.

Click here to subscribe to The Economist.

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Earth Is On The Cusp Of A Sixth Mass Extinction

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extinct extinction dead animals carcasses skulls voodoo creepy

Approximately 65 million years ago, when the dinosaurs went extinct, 75% of the planet's many species went with them. It was the world's fifth, and most recent, mass extinction event

Now, according to a July 25 review in the journal Science, the Earth seems to be at the cusp of a sixth mass extinction. Only this time, an asteroid is not to blame. We are.

"Human impacts on animal biodiversity are an under-recognized form of global environmental change," the team of ecologists and biologists warn in Science. "Among terrestrial vertebrates, 322 species have become extinct since 1500, and populations of the remaining species show 25% average decline in abundance." 

A third of all vertebrates, the scientists write, "are threatened or endangered."

There are several long-time drivers of what researchers call "defaunation"— the decline of various animal species. The study points to "overexploitation, habitat destruction, and impacts from invasive species" as continuing threats, but notes that soon, human-caused climate change will be the number one driver of defaunation. Diseases that come from pathogens introduced by humans are another growing threat.

The good news? We're not yet totally doomed. 

As David Biello writes in Scientific American:

To avoid the sixth mass extinction we will probably have to employ more aggressive conservation, such as moving species to help them cope with a changing climate. Think re-wilding: reintroducing species like wolves or beavers that were once present in a given ecosystem but have since disappeared. Aggressive conservation might also mean killing off newcomer species to preserve or make room for local flora and fauna.

As another study in Science notes, we've already made headway in saving some animals from what seemed like certain ruin.

But if humans as a species don't want to take our chances with a sixth mass extinction, we need to start taking drastic measures now. The momentum is already moving against us.

SEE ALSO: A Solar Storm Almost Ended Life As We Know It In 2012

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Intense Photos Show Aftermath Of Rare New England Tornado

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The National Weather Service confirmed that on the morning of July 28, a tornado hit Revere, Massachusetts, a city five miles from Boston. They are assessing the damage to try to figure out the details of the tornado, the second to hit New England in just two days.

Residents grew concerned after what seemed like an ordinary storm showed signs of "rotation," according to NBC Boston. A tornado warning was issued just 10 minutes before the tornado made landfall, Boston.com reports.

According to the Massachusetts State Police, there are no reported injuries, despite The Globe's reports of "collapsed roofs and gas leaks. People are being asked to avoid the area.

Here are some additional images from Twitter that appear to show storm damage around Revere. 

Here is the full statement from the National Weather Service:

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE TAUNTON MA
1148 AM EDT MON JUL 28 2014

...NWS METEOROLOGISTS ARE CURRENTLY SURVEYING STORM DAMAGE NEAR
REVERE IN SUFFOLK COUNTY...
...A TORNADO HAS BEEN CONFIRMED IN REVERE MASSACHUSETTS...

THE NATIONAL WEATHER SERVICE OFFICE IN TAUNTON MA IS CURRENTLY
CONDUCTING A STORM SURVEY FOR THE AREA NEAR REVERE IN SUFFOLK
COUNTY TAUNTON MA. THE SURVEY IS IN RELATION TO THE SEVERE
THUNDERSTORMS THAT MOVED THROUGH THE AREA ON JULY 28 2014.

A TORNADO HAS BEEN CONFIRMED TO HAVE OCCURRED IN REVERE
MASSACHUSETTS THIS MORNING. THE DAMAGE ASSESSMENT IS STILL ONGOING
TO DETERMINE ADDITIONAL DETAILS SUCH AS THE MAXIMUM TORNADO
INTENSITY...ALONG WITH THE LENGTH AND WIDTH OF THE DAMAGE PATH.

A FINAL ASSESSMENT INCLUDING RESULTS OF THE SURVEY ARE EXPECTED
TO BE COMPLETED AND TRANSMITTED VIA A PUBLIC INFORMATION
STATEMENT BY LATER THIS AFTERNOON.

IT WILL ALSO BE AVAILABLE ON OUR WEBSITE...WHICH CAN BE FOUND AT
WEATHER.GOV/BOX.

 

SEE ALSO: Boston Suffers Extensive Damage And Flooding After Violent Storm And Rare Tornado

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Scientists Discovered 360 New Bird Species This Year

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somali ostrich bird wildlife

Did you know there are two species of ostrich? Don't worry if this is news to you — scientists didn't know that for sure either until this year, when the Somali ostrich (Struthio molybdophanes) of Ethiopia, Somalia, Djibouti and Kenya was declared a separate species from the common ostrich (S. camelus).

Previously considered a subspecies, the Somali ostrich has now been added — along with 360 other newly discovered bird species— to the International Union for Conservation of Nature's Red List of Threatened Species.

The Red List update come from an assessment of the world's birds of prey, seabirds, water birds, owls and similar species (collectively known as nonpasserine birds, because all other birds come from the order Passeriformes) by the conservation organization BirdLife International.

The Somali ostrich and the other 360 new species were effectively hidden in plain sight for decades. Because they were not recognized as species until now, no one had ever assessed their conservation risks. And they are definitely at risk: According to BirdLife, 25% of these newly recognized species are considered threatened and have been added to the Red List under its vulnerable, endangered or critically endangered categories. That's compared with just 13% of all bird species that have been identified as being at similar risk.

The Somali ostrich and other birds were finally recognized as new species because BirdLife created a new system to categorize bird taxonomy in order to create a more consistent approach for determining species' conservation risks.

"The new species criteria are basically a scoring system of physical characteristics — plumage, song, etcetera — that are used to distinguish between closely related species," says Martin Fowlie from BirdLife's communications team.

The new criterial focus on mating signals, songs and plumage because "they play a role in setting real biological species limits, by determining whether interbreeding can or will occur," University of Oxford zoology lecturer Joseph Tobias explained in a recent issue of World BirdWatch magazine (pdf). It does not, however, use molecular data because "there is currently no agreement about a surefire threshold of genetic divergence indicative of species status," Tobias wrote.

The Somali ostrich faces numerous threats — egg collection, hunting and habitat loss among them — but at least it's still around. Other new (and previously hidden) species added to the Red List may not be so lucky. They include the Belém curassow (Crax pinima) of Brazil, which hasn't been seen since 1978. It lives (or lived) in what is now the most heavily deforested region of the Amazon rainforest.

The blue-bearded helmetcrest (Oxypogon cyanolaemus), meanwhile, hasn't been seen since 1946 and is only known from museum samples. The Colombian hummingbird lived in a forest that has since been burned down to make way for agriculture.

In addition to the new species the Red List update also provides new information on several previously known birds. The bearded vulture (Gypaetus barbatus), which faces threats from diclofenac poisoning and collisions with power lines is now listed as near threatened.

The Bugun liocichla (Liocichla bugunorum) of the Himalayas (shown to the right) has been reassessed as critically endangered following the construction of a road through its only habitats, which have also suffered fires.

The second half of BirdLife's comprehensive review of the world's feathered species is due in 2016 and will cover all 5,000 or so passerine birds — including, no doubt, a few more new species.

SEE ALSO: The Most Badass Birds On The Planet

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The Future Of Medicine Depends On The Most Fragile Places On Earth

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Palmyra Atoll Coral Reef

Venomous cone snails sting passing fish, paralyzing them so they can be digested alive. Fire coral causes painful scrapes and infections when touched, a means of self-defense. And certain reef-dwelling mollusks swallow microbes to build up a protective coat of toxins on their skin.

Coral reefs and other rare environments aren't just fascinating and beautiful. The potent and diverse chemicals created by nature might hold the key to better treatments for cancer, HIV, and many other diseases that stymie doctors — but only if we can reach them in time.

Harvesting and adapting these natural compounds is crucial to the advancement of modern medicine. There's just one problem: Many of the best potential sources for new drugs are at risk of extinction.Nudibranch

Finding Drugs In Nature

The first modern antibiotic, penicillin, comes from a fungus.

Ancient Greeks used molds to fight infections. Polynesian seafarers and 14th-century Chinese-derived painkillers from reef creatures. And in recent years we've learned much more about how to extract chemicals and medicines from natural sources.

"Mother Nature has been doing her chemistry over the last 3 billion years," says David Newman, chief of the Natural Products Branch of the National Cancer Institute. "She isn't making anti-tumor compounds," he explains, but the same chemical that a sea sponge uses to fight predators might also be able to kill cancer cells or viruses.

Cone snail venom is now being used as a painkiller — one that's 50 times more potent than morphine — that eliminates phantom limb pain in amputees. Tunicates, marine invertebrates frequently found around coral reefs, provide anticancer and antiviral chemicals. AZT, the first effective drug against AIDS, comes from a chemical produced in a lab, but the chemical was first found in, and modeled from, a Caribbean sea sponge.

Scientists from the National Oceanic and Atmospheric Administration say that more than half of modern pharmaceuticals derive from the natural world. In particular, they say that reefs and the creatures that live on and around them show special potential for medicine.

A 2012 review found that of the new drugs approved to fight cancer between 1981 and 2010, only 20.2% were purely synthetic — meaning purely made in a lab, not found in nature or made, derived, or copied from something natural. The same was true for new drugs used to fight infections. Just 22.6% of those were purely synthetic.

Tunicate Coral ReefKilling Off Potential Treatments

Nature has amazing medical potential because of its biodiversity, but finding new medicines is hard work.

For every medically useful molecule found, thousands have been tested unsuccessfully. Some of those useful molecules, and the species that produce them, can be found in only a few vulnerable places.

"When we lose a single reef or part of a forest due to changes in climate or other causes, we do not know what we have lost," says Newman.

Natural resources with great potential have been squandered before.

Newman tells the story of a researcher who in the late 1980s collected samples of biological material from a certain type of algae growing among mangroves on the coast of a Caribbean island. Tests later showed that the algae contained what seemed to be a promising new antitumor agent. But when the researcher returned, the mangroves had been uprooted, and the area filled in and turned into a golf course.

Why Coral Reefs Matter

The ocean in particular is considered both one of the least explored and potentially most useful sources of new medicines. Called the "medicine cabinets of the 21st century"by the National Oceanic and Atmospheric Administration, coral reefs are the most biodiverse sites in the sea.

But they're also the most vulnerable.

They cover less than 1% of the ocean's floor, and more than a quarter of marine life directly depends on them. But they are in dire shape because of the effects of rising temperatures, pollution, and ocean acidification. Many researchers think it might already be too late to save reefs.

According to the latest report from the Intergovernmental Panel on Climate Change, warming and acidification will cause high extinction rates throughout the tropics, where most reefs are located.

And they aren't the only sites at risk.

"We are effectively undoing the beauty and the variety and the richness of the world which has taken tens of millions of years to reach," Elizabeth Kolbert told NPR's Terry Gross while discussing her book "The Sixth Extinction."

There have been five mass extinctions in earth's history, when some tragic event caused the number of species on the planet to plummet. Manypeoplethinkthatclimate change, ocean acidification, and habitat destruction have put us on the cusp of a sixth extinction event, causing the "extinction of one-third of all reef-building corals, a third of all freshwater mollusks, a third of sharks and rays, a quarter of all mammals, a fifth of all reptiles, and sixth of all birds," according to Kolbert.

Red Sea Coral ReefIf These Sites Are Lost

The loss of much of the world's biodiversity is only one of the expected effects of climate change. But that one effect could have an even greater impact on humanity than we know.

It can't be said with certainty that climate change will destroy the molecule that would provide the perfect cure for leukemia or breast cancer or the chemical that could universally eliminate HIV.

New compounds with medical potential could theoretically be found anywhere. A molecule that could treat anthrax was recently found in underwater sediment off the coast of California. The source of an amazing new drug for fighting cancer might exist in some rare, never-analyzed species of fungus growing in New York's Central Park.

But so far, many of the most promising sources of new medicine in the world are in the biodiverse hotspots most at risk of being lost. Sites like reefs are beautiful, interesting places. But even if they weren't, they'd be worth preserving for their medical potential alone.

Unfortunately for much of the world, it could already be too late.

SEE ALSO: Hiking Through Peru Showed One Journalist The True Dangers Of Climate Change

Don't miss: Earth Is On The Cusp Of A Sixth Mass Extinction

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Airbnb Says It’s Better For The Environment Than Hotels

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Airbnb treehouse

Airbnb today announced a self-commissioned study with an interesting claim: that Airbnb guests “use 63 percent less energy than hotel guests.”

The study rests on a survey by the Cleantech Group consultancy, researched between February and April of this year. The consultants say they surveyed “over 8,000 … hosts and guests,” and then compared the responses with “research on residential and hotel sustainability levels and practices.”

According to the study, North American Airbnb guests are more likely to use public transportation and to recycle than hotel guests are. Airbnb says this saves “the equivalent of 270 Olympic-sized pools of water,” and avoids “the greenhouse gas emissions equivalent to 33,000 cars on North American roads.”

Airbnb also says that 95 percent of its North American hosts recycle — far higher than claimed U.S. averages, which vary loosely between 58 percent and 75 percent, depending on where you look.

The study should certainly be taken with a grain of salt. In addition to the fact that Airbnb commissioned the study, many of the factors considered appear to rest on anecdotal evidence, and it’s comparing results from the survey with separate research results — not exactly a recipe for generating scientific results.

That said, Airbnb’s arguments are technically plausible and may aid in its quest to win over skeptical lawmakers.

Reached by VentureBeat, Airbnb refused to allow its full study to be published online. The company has yet to explain why it does not want the entire study published. You can view more highlights below.

SEE ALSO: Airbnb has banned the condo squatters for life

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Giant 6-Foot-8 Penguins Roamed Antarctica 40 Million Years Ago

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emperor penguins antarcticaNewly unearthed fossils from Antarctica have revealed that the continent was once home to the biggest species of penguins ever discovered.

The huge flightless bird would have stood two metres tall – from beak tip to toes - and weighed around 115 kgs.

“This is definitely a big penguin," said Dan Ksepka, curator of science at the Bruce Museum in Greenwich, Connecticut, in an interview with New Scientist.

Palaeeudyptes klekowskii has been dubbed the “colossus penguin”, and is the most complete fossil ever uncovered from the Antarctic.

In comparison Emperor penguins weigh 46 kilograms and reach heights of 1.36 metres, 0.2 metres above their standing height. Another extinct penguin used to hold the height record, at around 1.5 metres tall.

Carolina Acosta Hospitaleche, of the La Plata Museum in Argentina has been excavating fossil deposits on Seymour Island, off the Antarctic peninsula.

Large penguin

This was a warmer region 40 million years ago, with a climate like that of present-day Tierra del Fuego, the islands at the southern tip of South America.

The site has yielded thousands of penguin bones. Earlier this year, Acosta Hospitaleche reported the most complete P. klekowskii skeleton yet, although it contained only about a dozen bones, mostly from the wings and feet

Now she has uncovered two bigger bones. One is part of a wing, and the other is a tarsometatarsus, formed by the fusion of ankle and foot bones.

The tarsometatarsus measures a record 9.1 centimetres.

Based on the relative sizes of bones in penguin skeletons, Acosta Hospitaleche estimates P. klekowskii was 2.01 meters long from beak tip to toes.

Its height will have been somewhat less than its length owing to the way penguins stand. But it was nevertheless larger than any known penguin.

Larger penguins can dive deeper and stay underwater longer than smaller ones. A giant like P. klekowski could have stayed down for 40 minutes, giving it more time to hunt fish, says Acosta Hospitaleche.

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Buying A New Car Is Better For The Environment Than Driving An Old One

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driving car

You've probably heard it at some point: A friend claims his older vehicle is far greener than the new car with much higher fuel economy you just bought.

That's because, he says, the old car didn't require all the energy and natural resources your car consumed as it was built.

But is that older car really greener?

The short answer: No.

The longer answer is also 'no', but it may help educate your friend on why that beloved 20-year-old rattletrap isn't as green as he likes to think.

The environmental cost of manufacturing

It's easy to see why many people think that running an old car would be greener than regularly buying new ones.

Building a new car is an energy- and resource-intensive process. You need to mine ore out of the ground and oil from the earth or sea, turn them into the raw materials for vehicle parts, turn those supplies into actual components, and then assemble the resulting parts into a car.

At the end of it all, you've got a rolling ton or more of metal, plastic, glass, and rubber that didn't exist before. That carries an environmental cost long before the car turns a wheel.

But it's here that we return to a 2000 study by M.A. Weiss et al., entitled On The Road In 2020: A life-cycle analysis of new automobile technologies.

The study reveals that fully 75 percent of a car's lifetime carbon emissions stem from the fuel it burns, not its production. A further 19 percent of that is production and transportation of the fuel, leaving just six percent for the car's manufacture.

These figures vary--a more recent Volkswagen study suggests that with vehicle efficiency rising steadily, 68 percent of the car's lifetime emissions came from driving it, while the manufacturing process accounts for a higher 22 percent.

Some of this discrepancy is down to the VW in question, an ultra high-efficiency model available in Europe. The less energy a car consumes through its lifetime, though, the less that fuel use contributes to its lifetime emissions.

The numbers

We can actually work out the relative merits of running an old car and a newer, more efficient one. The numbers show why it becomes better to buy a new car rather than keep an older one running.

Let's say you drive an older car that does 30 mpg, and you drive 15,000 miles per year. The newer car does 40 mpg--as many modern compacts can, or will shortly.

During those 15,000 miles, your old car will use 500 gallons of gas. The newer car: 375 gallons.

That 30 mpg is also about 290 grams per mile of CO2; 40 mpg works out as 217 g/mi. Over the course of the year, the old car will emit 4.35 tons of CO2, the newer car 3.25 tons.

But if you've been running the older car for 10 years, it has emitted over 43 tons of CO2 before the new car has even been built. That number will keep on going up, so bear that in mind if you drive something made in the 1990s or earlier.

MORE: Five Big Myths About Green Cars And Gas Mileage, Debunked

According to The Guardian, citing How Bad Are Bananas? The Carbon Footprint of Everything by Mike Berners-Lee, a minicar has a production footprint of around 6 tons of CO2 equivalent. A larger car--a Ford Fusion--is about 17 tons before it hits the road.

If we assume our 30- and 40-mpg compacts both account for about 12 tons of CO2 during production, it's easy to work out just how long it would take for a new car to offset its production.

In its first year, the new car is responsible for 15.25 tons of CO2 (12 for production, 3.25 during use). That's about 3.5 years of using the old car at 30 mpg, in terms of carbon emissions.

Of course, the older car's production also adds to its tally--and it's less likely that older vehicle included as many recycled materials, or were built as efficiently as the newer car.

Ultimately, by the time the 30-mpg car is 10 years old, it's been responsible for 55.5 tons of CO2, and that amount continues to accrue at a faster rate than those of the new car.

You could run it for 3.5 years before the production and first year's use of a new car matched it--but ultimately, its 10-year lifetime produces far greater emissions than those of a new vehicle.

Caveats

There are huge variables in such calculations, of course.

If your old car already does 40 mpg, for example--maybe you have a flyweight Honda from the early 1990s--then it will have produced much lower lifetime carbon emissions and the new car will take longer to catch up.

But it's worth pointing out that in terms of emissions other than carbon dioxide (CO2), that old car is far more polluting than a modern vehicle.

Less stringent emissions standards from the 1990s and before permit far more unburned hydrocarbons, oxides of nitrogen, and carbon monoxide per mile to be emitted than in today's cars.

If for some reason you trade from that old 40-mpg Honda to a modern car that does only 35 mpg, then while the older car's lifetime tally will start higher, the newer car will eventually reach a point where the older car's emissions are lower.

Again, that is, if you ignore the cleanliness of those lower tailpipe emissions.

Then there's maintenance--a newer car will typically use less oil, require fewer new parts and require less intensive maintenance than an older one. That older one will be consuming other resources, not just fuel, throughout its life.

Finally, it can't be overstated that production of a vehicle is inherently an energy-intensive process. Once iron ore is extracted from the ground, it cannot be put back--the new car is ultimately another vehicle on the road that wasn't there before.

In developed countries--the U.S., most of Europe, and Japan--vehicle population is now close to static. For several years during the recent recession, the U.S. actually scrapped more cars than were sold new, meaning vehicle population actually declined.

But with 1.2 billion vehicles on the planet today, and the total rising to perhaps as much as 2 billion by 2035, the overall emissions burden is clearly rising. Nonetheless, that doesn't affect your friend's old car's emissions--which remain higher over its lifetime than your new car's.

New still beats old

All the data show that a car's lifetime energy use for propulsion, meaning the fuel or energy that it consumes to move itself about, accounts for a far greater proportion of its lifetime environmental impact than its production.

It's great that your friend likes her old car. Kudos to her for keeping it running, rather than letting it rot into the earth.

There are many reasons to run an old car--character, driving sensations, looks, and the memories of the journeys you've accomplished.

And, to be fair, the car you own is usually going to be cheaper than buying a whole new vehicle--financial reasons count for a lot.

But unfortunately, running an old car because it's greener isn't one of those reasons.

New cars, in that respect, will always be better than old ones.

This article originally appeared at Green Car Reports. Copyright 2014. Follow Green Car Reports on Twitter.

SEE ALSO: The Music Industry Is Suing Ford And GM Over The Audio Systems In Their Cars

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Before And After GIF Shows Terrible Impact Of California's Drought

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cali drought comparison big

In its weekly report issued on July 31, the U.S. Drought Monitor reported that 82 percent of the state of California was in an extreme drought and 58 percent was in exceptional drought—up from 79 and 36 percent just two weeks ago. The drying of farmlands and suburbs is mirrored by the shrinking of the state’s reservoirs.

The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) instrument on NASA’s Terra spacecraft captured these false-color views of central California on April 5, 2011, and May 15, 2014. ASTER collects data in infrared, red, and green wavelengths of light, which are then combined to make false-color images where vegetation appears red; buildings and roads are white and gray; water is dark blue; and dry, barren land is tan.

The images show an area north of Fresno, California, between the San Joaquin Valley and Yosemite National Park. The scene includes two reservoirs—H.V. Eastman Lake and Hensley Lake—that were built for flood control, irrigation, and recreation in the 1970s by the U.S. Army Corps of Engineers.

Check out the difference. Here's the 2011 image:

Screen Shot 2014 08 05 at 9.51.37 AM

And the one from 2014:

Screen Shot 2014 08 05 at 9.53.22 AM

Eastman was formed behind a dam across the Chowchilla River, and Hensley grew behind an earthen dam on the Fresno River.

At the time of the 2011 image, the landscape was comparatively lush with vegetation (which appears red) and the lakes were robust. After three years of drought, the 2014 scene shows a browned landscape and lakes that have shrunken considerably. In the lower left corner, farmland does not appear to have changed much. In fact, some areas look like they have more vegetation in 2014, though that could be because the 2011 image was taken earlier in the spring. Turn on the image-comparison tool to see the differences.

As of July 31, 2014, H.V. Eastman Lake stood at 8 percent of water capacity and Hensley stood at 6 percent, according to the California Department of Water Resources.

For more images from the California drought, please visit our event gallery.

SEE ALSO: 22 Devastating Effects Of Climate Change

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