What Could We Do If There Was An Asteroid On A Collision Course With Earth?

We recently posted about an asteroid that flewdangerously closeto our planet, and many followers have been wondering what one can do in case a space rock does come plummeting towards our heads.

While our natural inclinations will push us to scream in fear and/or appeal to our favorite deity, theres a lot that can be done to prepare, react, and maybe even stop threatening objects on acollision course withour planet.

Step One, Dont Panic

Asteroids and comets are a threat. They are a real and present danger to our planet. That said, we have not been sitting idling. NASAs Spaceguard survey has mapped the position and trajectories of 90 percent of the largest near-Earth objects (NEOs), thoselarger than 1 kilometer (0.62 miles). The impact from any of these objects would cause worldwide devastation, global cooling, and mass extinctions.

The good news is that none of these appear to be a threat, so at least on that front we can rest easy. We know of about 15,000 NEOs out of a likely 1,000,000, and both NASA and the European Space Agencyhave programs dedicated to discovering as many of them as possible.

NASA is now aiming to discover 90 percent of the NEOs larger than 140 meters (460 feet). These NEOs are a little bit more worrying, as we have so far discovered only about 8,000 objects between 100 and 1,000 meters (0.06 and 0.62 miles), withmany still missing from the roll-call. If one of these bad boys were to hit land, they could create a crater as large as a small city. If they hit an ocean, they would generate a tsunami.

Smaller objects wouldnt be too dangerous on water, but they could be problematic on land. Theyd most likely burn up in the atmosphere, but the shockwave could be still very dangerous. The Chelyabinsk meteorthat fell in Russia in 2013 caused damage to over 7,200 buildings and injured 1,491 people. And it was only 20 meters (65 feet) in diameter.

Initiatives like Asteroid Daywere created with the precise intention to raise awareness of such adanger.

content-1484239864-shutterstock-55135175Meteor Crater panoramic view in Winslow, Arizona, USA. Shutterstock/Nikolas_jkd

Getting Ready For The Worst

While the threat is there, the odds appear to be in our favor. The largest object that will have a close shave with our planet is Apophis in 2029 and then again in 2036. Theres only a 1-in-250,000 chance that it would hit Earth, but the first close encounter might alter its orbit a bit, making it more dangerous.

So, if we were to discover NEOs heading to Earth, would we have the capabilities to defend ourselves? A panel of experts discussed this very topic last December, and they concluded that humanity is currently not ready to destroy or deflect a threat of this kind.

Our main enemy is time. While wemight have the technology ready to deploy, we might not have enough time to launch it. Currently, scientists are studying the best strategies to deal with asteroids in order to have thebest plan ready to defend ourselves.

Of the various possibilities so far, theres the nuclear option, theres the optionof using lasers, hooking the NEO and dragging it away, or having a fast rocket simply slam into it. But we cant just get up and do it. We need to take into account many variables (size, density, distance from us, etc.) before contingency plans can be drafted.

We are very carefully doing our homework before finals week,” Dr Catherine Plesko stated during aconference. “We dont want to be doing our calculations before something is coming. We need to have this work done.”

Lacking defenses doesnt leave us helpless, though. NASA and the Federal Emergency Management Agency (FEMA) have already run three simulated scenarioson how to intervene if we were put in such peril. The two agencies are building a portfolio of scenarios for potential future use, in order toensure they have information that would be critical in such an emergency.

Some may find these plans futile, but remember real life is not going to be like Deep Impact or Armageddon. We wont be able to fly a spaceship to the NEO and land on it to plant the bomb so it can be detonated at the last second. If we can land a crew there, its already too late. It would be too close.

Also, landing a crew would be incredibly difficult. Asteroids and comets are tiny. Rosettas comet 67P has a gravitational acceleration almost a million times smaller than Earth. The landing of the probe Philae was a phenomenal feat of engineering and even that one didnt go exactly according to plan. Philae bounced three times before settling down.

So dont land on an NEOand please dont send a group of untrained civilians to blow it apart. They might destroy your space station, and by blowing it apart, you might end up with hundreds more large fragments heading for Earth on unpredictable orbits.

content-1484240123-comet-on-17-august-20Comet 67P/Churyumov-Gerasimenko as seen by Rosetta. ESA

What To Do In The Mean Time

Theres no reason to lose sleep on the possibility of apotential asteroid impact, but at the same time, we cant bury our heads in the sand. So what can all of us do to prepare? Worry less about stocking up on tin goods and do more toraise awareness of the problem.

Join an activity for Asteroid Day, write to your political representative about it, and make sure that the threat is discussed with level-headedness.

Ideally, we want a dedicated space observatory to monitor these objects and a rocket (or several) ready to go if necessary. Both are expensive, but if theres enough political will, we can be ready.

Disaster movies always show humanity coming together and working hard even in the face of impossible odds. Perhapsthats the most realistic parts of them.

Read more: http://www.iflscience.com/space/what-could-we-do-if-there-was-an-asteroid-on-a-collision-course-with-earth/

The Huge “Asteroid” Set To Fly Past Earth Today Is Actually A Dead Comet – And It Looks Just Like A Skull!

The Universe has a very special treat for us this Halloween: a skull-shaped dead comet posing as an asteroid. The massive space rock will whizz past the Earth today, providing the best chance for radar astronomers to observe such an object for many years to come.

The asteroid, officially named 2015 TB145, will safely pass by the Earth on Halloween around 1pm EDT (1700 UTC) at a distance of 486,000 kilometers (302,000 miles) thats 1.3 times the distance from the Earth to the Moon. Using a combination of optical and radar observatories, including NASAs Infrared Telescope Facility (IRTF) on the slopes of Mauna Kea, Hawaii, scientists observed the large space rock and made some surprising discoveries.

First discovered on Oct. 10, scientists thought they were seeing a massive asteroid with a very elongated orbit. However, new observations made on Oct. 30 with the National Science Foundations 305-meter (1,000 foot) Arecibo Observatory in Puerto Rico reveal that 2015 TB145 may actually be a dead comet, having shed all its volatiles after many orbits around the Sun. This would also help to explain its funky orbit, which resembles the typical orbit of a short-period comet rather than an asteroid.

“We found that the object reflects about six percent of the light it receives from the sun,” said Vishnu Reddy, a research scientist at the Planetary Science Institute, Tucson, Arizona. “That is similar to fresh asphalt, and while here on Earth we think that is pretty dark, it is brighter than a typical comet which reflects only 3 to 5 percent of the light. That suggests it could be cometary in origin — but as there is no coma evident, the conclusion is it is a dead comet.”

The new measurements also tell us that the celestial body is much darker than previously thought, reflecting only about six percent of the light that hits it. This also tells scientists that we are dealing with a cometary body as comets are typically darker than asteroids. Its dark color helped to conceal its true size, and scientists were surprised to find that it is spherical in shape and measures approximately 600 meters (2,000 feet) wide roughly the size of 5 football fields. The zombie comet is speeding through space at 126,000 kilometers per hour (78,293 mph) and rotates once every five hours.

Arecibo also provided us with the first radar images of the dead comets surface and we see an eerie view perfectly suited for Halloween. Darker eye socket-like features on the surface mostly likely craters formed over time by melting ices or impacts give the comet a skull-like appearance. But thats really an optical illusion explained by a phenomenon known as pareidolia, which tricks our brain into seeing patterns that arent really there.

“The IRTF data may indicate that the object might be a dead comet, but in the Arecibo images it appears to have donned a skull costume for its Halloween flyby,” said Kelly Fast, IRTF program scientist at NASA Headquarters and acting program manager for NASA’s NEO Observations Program.

Despite being discovered earlier this month, scientists have a great understanding of the comets orbit. Even at its closest approach today, it is still further away than the Moon and is no threat to the Earth. However, its close flyby presents an excellent research opportunity. By studying objects like 2015 TB145 up close, we can determine its composition and plan for future encounters with asteroids that may pose a real threat.

Read more: http://www.iflscience.com/physics/huge-asteroid-set-fly-past-earth-today-actually-dead-comet-and-it-looks-just-skull

Our Most Distant Space Exploration Mission Depends Upon These Next Few Weeks

In two weeks, scientists will get an unprecedented look at a distant Solar System object one that will be visited by a spacecraft in the not too distant future. And these observations will be vital in keeping that spacecraft safe from harm.

The object is called MU69, thought to be a remnant of the early Solar System. Its the target of the New Horizons spacecraft, which is haring towards it at 56,000 kilometers (35,000 miles) per hour after flying past Pluto in 2015. New Horizons will fly past MU69 on January 1, 2019, the most distant object weve ever explored.

Things are a bit complicated though, as very little is known about MU69. We think its about 40 kilometers (25 miles)across, and we have a rough estimate of its orbit. But to make the flyby a success, we need to learn more.

In particular, we need to know if there are any hazards near MU69, such as rings, dust, or even small moons. Any of these could affect planning for the flyby, which is less than two years away. Scientists had seven years to prepare for the Pluto flyby, but this one will be a lot more last minute.

“We need to find out if there are rings or other dust that would be hazardous,” Alan Stern, New Horizons Principal Investigator, told IFLScience. “[If not] it would mean we’re flying in blind.”

So thats what makes this upcoming event so important. On June 3, and then July 10 and 17, MU69 will block the light from three different stars. Known as an occultation, these events will allow scientists on Earth to study its shape and brightness.

Each occultation will be incredibly brief, lasting just a couple of seconds. So to maximize the amount of data they will get, the New Horizons team are deploying small telescopes across the globe.

More than 50 telescopes will be positioned through Argentina and South Africa, the regions where the shadow of MU69 will pass, to maximize the data return. In addition, NASAs SOFIA telescope which flies in a converted Boeing 747SP will also have its eye trained on the event.

NASA’s SOFIA telescope will be used to peer at MU69. NASA

If there is a lot of debris there, the trajectory of the flyby will need to be altered to keep New Horizons at a space distance, and prevent it being damaged or destroyed.

We also dont know how reflective MU69 is. New Horizons will be snapping images, so mission scientists need to know what exposure times the cameras and instruments need. Get it wrong, and we could miss out on a ton of science.

Spacecraft flybys are unforgiving, Stern said in a statement. There are no second chances.

Read more: http://www.iflscience.com/space/our-most-distant-space-exploration-mission-depends-upon-these-next-few-weeks/

This Awkward Feathered Dinosaur Was Almost Blown Up By Dynamite

Please, if youre blowing up the side of a mountain or part of a quarry, double check you havent got any dinosaurs laying around. Fossils are rather wonderful, fragile things, and they wont stand up too well against the awesome power of dynamite.

Such an unfortunate fate almost took hold of a newly discovered dinosaur found buried beneath a Chinese construction site. Although parts of the 72-million-year-old fossil were in fact blasted to kingdom come, the workers decided that it probably wasnt a good idea to continue without contacting some paleontologists.

That they did. As a rather splendid study in the journal Scientific Reports describes, the new creature represents one of the last flurries of evolution for the dinosaurs before almost all of them were wiped out by an asteroid, a lot of fiery volcanism, and the rise of mammals.

Its been named Tongtianlong limosus, which means muddy dragon on the road to heaven. It was found preserved in ancient mud, with its limbs splayed and its winged forearms spread out across the ground. It would have had a snubbed, toothless, beak-like mouth, a small head crest, and a parrot-like skull. It was roughly the size of a sheep, and likely had an omnivorous diet.

It’s part of a group of very advanced bird-like, feathered dinosaurs called oviraptorosaurs, Dr Stephen Brusatte, a paleontologist at the University of Edinburgh, told BBC News.

The fossil in all its wonky glory. Lu et al./Scientific Reports

The oviraptorosaurs first emerged during the Cretaceous Period, the twilight chapter in the age of the dinosaurs. They ranged greatly in habitat, diet and size, with some being roughly proportional to a turkey, and others like the appropriately-named Gigantoraptor, which was 8 meters (26 feet) long and weighed around 1.3 tonnes (1.4 tons).

They belonged to the overarching group Maniraptora, which gave rise to both flying dinosaurs and their contemporary descendants, birds.

Modern birds came from dinosaurs, Brusatte said, and its dinosaurs likeTongtianlongthat give us a glimpse of what the ancestors of modern birds would have looked like.

Living alongside some increasingly diverse pterosaurs and primitive mammal-like critters, these bird-like beasts with their colorful plumage and varying ability to glide were a preview of the dinosaurs that would survive the incoming global catastrophe one that would kill off up to 75 percent of life on Earth.

A recent study documented that dinosaurs were in decline for about 50 million years before the asteroid hit. The number of new species appearing on the world stage was being gradually eclipsed by the number that were becoming extinct, and some have argued that they were destined to die even before the giant space rock finished them off.

However, the complex mixture of physical characteristics displayed by T. limosus reveals that, at least in some pockets of the world, dinosaurian lineages were continuing to flourish and diversify at breakneck speed. This so-called Muddy Dragon, then, represented one of the very last examples of dinosaur evolution before they were wiped off the face of the Earth.

Its lucky that dinosaurs appeared to be fairly clumsy. This one probably died by tripping over and falling into some mud, which preserved it rather spectacularly.

Another dinosaur an Iguanodon fell into an acidic swamp millions of years earlier, which resulted in its brain being pickled and conserved long enough for researchers to stumble across it. Thanks to this series of unfortunate events back in the Cretaceous, the world now has its first fossilized dinosaur brain.

The location of the fossil site. Lu et al./Scientific Reports

Read more: http://www.iflscience.com/plants-and-animals/awkward-feathered-dinosaur-almost-blown-up-dynamite/

Kepler Space Telescope Discovers More Potentially Habitable Planets

Yesterday researchers from the NASA’s Kepler Space Telescope announced the discovery of 833 more candidate planets, 104 of which have the potential to harbor life. Included in that 104 in their respective Goldilocks Zones are 10 that are roughly the same size as Earth. As of this announcement, the total number of exoplanets discovered by Kepler since its launch in 2009 is now at 3,538. Its mission is to explore exoplanets and discover which ones are similar in size to Earth and are capable of supporting life. The announcement is coming from Kepler Science Conference, which is hosting over 400 scientists representing 30 countries.


According to William Borucki, the principal investigator for Kepler’s science mission, these discoveries “[open] a new era of exploration of our galaxy.” The first potentially habitable planet was announced two years ago, and since astronomers now believe there that most stars in the galaxy have at least one planet there is the possibility of many more potentially life-harboring discoveries to come.


This spring, Kepler’s mission was changed when two out of the four wheels used to point the telescope toward its targets broke, and NASA scientists were unable to repair them. Kepler completed its initial mission in 2012, and is currently completing an extended mission. Despite this, there is still a full year’s worth of data that has not been processed yet as Kepler monitored 150,000 stars and recorded data once every half hour for those four operational years. 


One analysis of Kepler’s data suggests that around 20% of sun-like stars have an Earth-like planet. So far, there have not been any reports of any such planet that completely mirrors Earth in terms of habitability and revolution length around a star like ours, but astronomers will continue to search. 

Read more: http://www.iflscience.com/space/kepler-space-telescope-discovers-more-potentially-habitable-planets

Observations Of The Cosmic Snake Lead To Better Understanding Of Star Formation In The Early Universe

Stars form in dense clumps of gas and dust that we call stellar nurseries. Hubble has seen many stunning examples of these objects in our own and other galaxies. Yet a surprising and unexpected series of observations suggest that stellar nurseries in the early universe packed a lot more material in the same space. But this might not actually be the case.

Thanks to new observations of the “Cosmic Snake”, a French-Swiss collaboration produced a detailed study of stellar nurseries in these distant galaxies. The snake is actually a very distant galaxy, which is serendipitously located behind the core of galaxy cluster MACS J1206.2-084747. The cluster is so massive it distorts and bends light like a lens so that distant galaxy light is amplified and ends up looking like a snake.

“The amplified image is more precise, luminous, and allows us to observe details up to 100 times smaller,” lead author Dr Antonio Cava, from the University of Geneva in Switzerland, said in a statement.

The team studied gas clumps which are about 3,200 light-years across to a detail of roughly 100 light-years. In previous observations, these regions were estimated to contain enough gas to make over 3 billion stars like our Sun but the new study, published in Nature Astronomy, shows that most of them are smaller than that, with the average clump weighing around 100 million times the mass of the Sun. This is broadly consistent with the simulations.

The team highlighted how the apparently giant clumps are either smaller than previously thought or appear as one despite being made by smaller (unresolved) components. These observations wouldn’t have been possible without gravitational lensing.

The cosmic snake. NASA, ESA, Cava et al.

“We have reduced the differences between what we observe in the nearby universe and in distant galaxies from a factor 1,000 to a factor 10,” explained Professor Daniel Schaerer from the Geneva Observatory.

The research is a serious advancement in understanding star formation in the early universe. We have estimated that star formation in galaxies peaked around 3.5 billion years after the Big Bang. The Cosmic Snake is producing 30 times more stars than the Milky Way and there are galaxies making 100 if not 1,000 times more stars than our own.

Read more: http://www.iflscience.com/space/observations-of-the-cosmic-snake-lead-to-better-understanding-of-star-formation-in-the-early-universe/

Ancient Rock Offers New Clues About Past Habitability of Mars

New analysis of a martian meteorite that fell to Earth 13,000 years ago has revealed clues about prior habitability on the red planet. The rock, which was recovered from Antarctica 30 years ago, originated on Mars 4 billion years ago, when water is believed to have covered the planet’s surface. Understanding the chemical composition of the rock will help scientists determine if Mars could possibly have sustained life. Robina Shaheen of the University of California, San Diego is lead author of the paper, which was published in the Proceedings of the National Academy of Sciences.

“Minerals within the meteorite hold a snapshot of the planet’s ancient chemistry, of interactions between water and atmosphere,” Shaheen said in a press release.

The potato-shaped meteorite is officially known as ALH84001, and is the oldest-known rock from Mars that we have found on Earth. It was formed from the cooled magma of a volcano, and trapped samples of minerals and carbonates, providing a snapshot of ancient martian conditions.

The relative abundances of isotopes of carbon and oxygen from the martian atmosphere allow the researchers to pinpoint the specific composition signature that existed on Mars at the time. While carbon dioxide dominates the Martian atmosphere, ozone is also present. However, the ozone is fairly odd due to the heavy isotopes of oxygen within it. These bizarre isotopes undergo a rare chemical reaction that imprints its chemical signature onto carbon dioxide.

“When ozone reacts with carbon dioxide in the atmosphere, it transfers its isotopic weirdness to the new molecule,” Shaheen explained.

This “weirdness” is also transferred when carbon dioxide and water create carbonates, leaving a very specific signature that can be detected. These levels of weird isotopes can be used to determine how much water may once have existed on the planet, which could give clues about potential habitability. Small quantities of water would lead to larger amounts of the odd isotope signature, while large oceans would have a smaller signature. Ultimately, the chemicals found within the meteorite do not suggest that Mars held the vast oceans that many believe once covered the red planet. Smaller bodies of water are much more likely.

“What’s also new is our simultaneous measurements of carbon isotopes on the same samples. The mix of carbon isotopes suggest that the different minerals within the meteorite had separate origins,” Shaheen continued. “They tell us the story of the chemical and isotopic compositions of the atmospheric carbon dioxide.”

The results suggest that Mars’ atmosphere now has higher levels of carbon-13 than it did then. At the time, Mars had low levels of carbon-13 and larger levels of oxygen-18. The changes in composition are likely due to the bombardment experienced on the planet billions of years ago in addition to the loss of atmosphere.

Unfortunately, the carbonate discovered by the team does not appear to have biological origins, and these data did not yield any evidence of ancient Martian microbial life. While NASA’s Curiosity rover did find traces of methane earlier this month, but this study was unable to corroborate those findings.

“We now have a much deeper and specific insight into the earliest oxygen-water system in the solar system,” concluded co-author Mark Thiemens, also of UCSD. “The question that remains is when did planets, Earth and Mars, get water, and in the case of Mars, where did it go? We’ve made great progress, but still deep mysteries remain.”

Read more: http://www.iflscience.com/space/ancient-rock-offers-new-clues-about-past-habitability-mars

A 30-Tonne Meteorite Has Been Discovered In Argentina

A meteorite weighing over 30 tonnes (33 US tons) was discovered in Argentina last weekend by a team of scientists from the Chaco Association of Astronomy, Argentinian news site La Nacion reports.

“It was a big surprise, Mario Vesconi, president of the Astronomy Association of Chaco, told the Argentine newspaper Clarin, translated via Google.

The meteorite was buried about 5 meters [16.4 feet] deep and has a width of almost 2 meters [6.6 feet], Vesconi told En Compactonea. He added that the meteorite, now called “Gancedo meteorite”, weighed 30,800 kilograms (67,900 pounds). However, the team said the meteorite willbe remeasured to officially confirm this.

The discovery was made in an area called Campo del Cielo which loosely translates to Sky Field or Field of Heaven found near the border between the provinces of Chaco and Santiago del Estero, northwest of the capital Buenos Aires. This site is covered in craters from an iron meteor shower around 4,000 years ago. The largest of these craters is 115 by 91 meters (377 by 298 feet).

Much of the local media described the find as the second largest meteorite ever discovered, although there were also unconfirmed reports of a 37-tonne (40 US tons) meteorite found at Campo del Cielo years ago. The largest known meteorite can be found in Namibia. Known as Hoba, this 60-tonne (66 US tons) meteorite is thought to have hit Earth around 80,000 years ago.

The potential value of the meteorite has not yet been discussed. However, local politician Livio Gutierrez welcomed Campo del Cielo’s new resident, saying it is a “milestone” in science andcould potentially boost the area’s tourism

Read more: http://www.iflscience.com/space/a-30tonne-meteorite-has-been-discovered-in-argentina/

A Sneak Peek at This Year’s Exciting Media Summit


Mashable Media Summit Speakers 2012

With less than one week until the Mashable Media Summit, tickets are selling out fast. Now’s your chance to purchase your ticket to learn about the hottest trends from the biggest leaders in media.

The Mashable Media Summit is a one-day conference that explores how new forms of technology are redefining media. The brightest minds in the industry will come together in a few days on Nov. 2 at The TimesCenter in New York City to explore the latest innovations in the space and the future of journalism. Get your tickets now.

Eventbrite - Mashable Media Summit 2012

We’ll be hitting on the biggest trends in media and what to watch for in 2013. Here is some of what you can expect to hear about at the Mashable Media Summit:

  • Digital media trends to watch in 2013

  • How to monetize without hurting community

  • Demystifying data-driven journalism

  • Why social media sites are becoming publishers

  • The future of journalism could be drones

  • How mobile is changing media for the better

  • What you should be measuring with social analytics

  • How brands are outpacing publishers

  • The digital transformation of politics

  • How Facebook has reinvented the entertainment industry

Other influential speakers joining the summit include Alexis Ohanian, co-founder of Reddit, Kay M. Matadi, head of entertainment at Facebook, Bonita Stewart, vice president of Americas Partner Business Solutions at Google, David Carey, president at Hearst Magazines, Joan Walsh, editor-at-large at Salon, and Tom Bedecarre, CEO of AKQA.

You can view the agenda online, and check out the highlights below of last year’s sold out Mashable Media Summit. Get your tickets now before it’s too late!

West Antarctic Glaciers Speeding Toward the Sea, Study Finds


This aerial photo of Wednesday, Oct. 31, 2012, shows the New York skyline and harbor after Superstorm Sandy struck the city.
Image: Mark Lennihan/Associated Press

Bad news from the Southern Hemisphere: the West Antarctic ice sheet is shedding ice at an accelerating rate, with six large glaciers in this region discharging nearly the same amount of ice as the entire Greenland ice sheet, according to a new study.

The study is the first to combine observations from satellites, radar data, and other remote sensing methods to construct a long-term record of ice movement trends for six of the fastest-flowing glaciers in Antarctica.

Published this week in the journal Geophysical Research Letters, the study examines glaciers in the Amundsen Sea Embayment of West Antarctica. The glaciers in this region include the Pine Island Glacier, which made headlines in recent years by discharging massive icebergs into the ocean.

This region also encompasses the Thwaites, Haynes, Smith, Pope and Kohler glaciers, each of which are behemoths in their own right.

A research team from the University of California at Irvine and NASA found that the total amount of ice coming off these glaciers has increased by 77 percent since 1973, with much of that increase coming since 2000. Together, these glaciers drain one-third of the West Antarctic Ice Sheet, or about 158 million square miles of ice, the study said.

We need to know how quickly and extensively parts of Antarctica as well as the Greenland ice sheet are melting in order to accurately project how high global sea levels are likely to rise during the next several decades. It’s melting land-based ice, not the melting North Pole sea ice, that contributes to rising seas.

Pine Island Glacier

A massive crack running about 18 miles Pine Island Glacier’s floating tongue in 2011.

Image: NASA

According to a 2013 report from the U.N. Intergovernmental Panel on Climate Change (IPCC), average global sea level rise will likely be in the range of 10.2 to 32 inches by the end of the century, depending on the amounts of greenhouse gas emissions between now and then.

If emissions continue on a business as usual path, which has been the trend in recent years, the IPCC said global average sea level rise could be closer to 40 inches — which would doom some low-lying coastal cities and nations, from Bangkok to Miami and Bangladesh.

Illustrating the high stakes involved in the fate of West Antarctica, the study found that these six glaciers contributed about 10% of all the global average sea level rise that occurred between 2005 and 2010. If all six glaciers were to melt completely (which is not expected to happen during this century), global average sea level would rise by a catastrophic 3.9 feet, the study said.

The new study also found, for the first time, that West Antarctic glaciers are not only flowing faster at the point where their base meets the ocean, which is known as the grounding line. Instead, areas as far inland as nearly 160 miles are also speeding up their march to the sea.

Until this study, it was not known that sections of glaciers deep into the interior are also speeding up their movement. This is a troubling sign because of what it implies for sea level rise in the future, according to the study’s lead author, Jeremie Mouginot of the University of California at Irvine.

“Increased ice discharge will have an impact on how [much] the sea level is going to rise,” Mouginot told Mashable.

Mouginot says most of the action is taking place at the grounding line, then having ripple effects inland.

In the same way that plaque slowly rots a tooth until it falls out, mild ocean temperatures are thought to be causing ice to thin and retreat where these glaciers meet the sea. This is likely setting in motion a chain of events that results in a far more unstable glacier.

Sea level rise

Projections of global mean sea level rise over the 21st century, depending on greenhouse gas emissions.

Image: U.N. Intergovernmental Panel on Climate Change

The grounding line positions of these glaciers have been retreating at a rate of 0.6 miles per year, the study found, which is among the fastest rates of glacier retreat in the world.

According to Mouginot, all six of the glaciers in this study come into contact with the same body of water, which indicates that higher sea surface temperatures are likely playing a role in speeding up melting. Other studies have found evidence for this in other parts of the globe, including Greenland, and in other parts of Antarctica.

“I think there is more warm ocean going beneath the ice shelf,” Mouginot says.

It’s not absolutely clear exactly what is causing ocean temperatures to increase in that area — but global warming from the increased amount of greenhouse gases in the atmosphere, is almost certainly playing a role.

“What I can say is, if you look at Greenland, it is changing, and West Antarctica is changing a lot,” Mouginot says. “And they are really far apart from each other. I don’t think it’s a regional change occurring. I think it’s more global.”

The IPCC is scheduled to release another major climate report on Sunday evening eastern time, which is expected to detail some of the likely impacts of global sea level rise during the next several decades, among other findings.

Read more: http://mashable.com/2014/03/28/west-antarctic-ice-melting-sea-level/