Unpacking Antarctica

[KU Choral Chant] EDITH TAYLOR: My research specialty is Paleobotany, which is the study of fossil plants. And what we can tell about the fossil climates from the plants. This particular grant was to collect Jurassic fossils from Antarctica. This is really the only site where there are very many of them. So it's 6,000 pounds worth of fossils that were collected in November/December by our team working in Antarctica. CARLA HARPER: Everybody says it's like Christmas in April, and it certainly is. EDITH: Carla Harper, our graduate student, collected a lot of fossil wood, which we use to learn about the ancient climates in Antarctica, because it wasn't always as cold as it is now. CARLA: So in addition to the Jurassic localities that we collected fossils, we also looked a time periods called the Permian and Triassic. So you have the Permian which was pretty cool, in temperature.

You have the Triassic which was much warmer. And then you have the Jurassic, which was even hotter. And so looking at that, you have intense climate change and what's amazing is that all the plants are changing, but the fungi and the microbes are pretty much doing the same thing back then as they are today. And so, if we can understand why do they have that sort of resilience, whereas the plants are changing, maybe we can see what they're going to be doing today in this ever-changing climate world. [music builds] CARLA: I've been working on Antarctic material for the past five years. But then to actually go there and then put it all into context, it's like, oh this is where everything comes from, this is why we do it. It reignited my passion, it's something I know I certainly want to continue with for a very long time.

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Can We Save Our Cities From Drowning?

The antarctic ice sheet is DEFINITELY MELTING! Here's a crazy idea: let's NOT wait until millions of people are homeless before we do something about it. Eh? Eh? Hello folks, Laci Green here for DNews. When it comes to the rising sea level, one of the key players is our Southern buddy Antarctica. Antarctica is a something of a neglected continent because basically nobody lives there– but it is about twice the size of Australia and contains 90% of the earth's ice. The entire continent is basically a 1 mile thick slab of ice. If the whole thing were to melt, the sea level across the planet would rise 200 feet. And humanity would be TOTALLY screwed. Fortunately, we're only SLIGHTLY screwed. Multiple studies published in the journal Science predict that we're looking at closer to a TEN foot increase in sea level across the planet by the year 2200. So hey! It's not 200 hundred feet…but 10 is still a lot, even across the projected 200 year period.

By the time your great-great-grandbabies are walking the earth, around 29,000 square miles of US land will be under water — land that is currently inhabited by over 12 million people. Researchers at Climate Central say that New York City, New Orleans, Miami and DC will be the areas that are most heavily flooded. Various coastal cities in Texas, New Jersey, New England, Virginia, California will also be severely affected. In Florida, the highest risk area, ⅓ of all its housing will go under, and because of what are essentially holes in Florida's bedrock, levees and seawalls will be useless. On a global scale, thirteen of the world's largest cities and about 25% of humanity rests in coastal areas that will be affected. Some inhabited islands, like the Maldives, are projected to go underwater completely. Of course, this kind of rise also poses a great threat for severe flooding during storms like Hurricane Katrina and Hurricane Sandy.

Plus tsunami zones from earthquakes will extend much further back into the land. BUT! Before you freak, keep in mind that this is something that will happen SLOWLY, over time. It's not an overnight thing. The melt predicted is also not reversible, it's gonna happen, so cities will need to figure out how they will handle the physical and economic impacts — a process that begins by scientists and policymakers working together and asking the right questions to get started. The American Geophysical Union is already asking: alright guys, what's our approach here? Should we build up our seawalls? Should we start to zone future buildings and real estate further up on the land? How will this affect our economy? To prevent even more sea level rising, we should also be seriously thinking about what role humans play in preventing more ice melting. The common response to this kind of news is usually fear (OH MY GOD!) followed by apathy (I DON'T CARE!).

I'd argue that the proper response isn't fear or apathy at all — it's action. Action in the form of prevention and adaptation. Time to roll up those sleeves and get to work. What do you think? Tell me about it down below and I'll see you next time with more science updates..

RESEARCHERS REVEAL A HIDDEN WORLD UNDER ANTARCTICA

RESEARCHERS REVEAL A HIDDEN WORLD UNDER ANTARCTICA There is a hidden mysterious world hidden away under Antarctica and researchers have revealed the giant wetlands that are 800 meters beneath the ice. The Whillans Ice Stream Subglacial Access Research Drilling, or WISSARD for short, a project that was financed by National Science Foundation, has taken researchers that step nearer to discovering just what lies underneath the ice that covers the majority of Antarctica. LAKE WHILLANS IS UNDER 800 METERS OF ICE IN WESTERN ANTARCTICA Reports have indicated that Lake Whillans, which was first located in 2007 and which covers more than 20 square miles, is under the 800 meters of ice that is found in Western Antarctica and researchers have said that this is very similar to the wetland. The researchers are hoping that more studies will mean they can understand better how the level of the sea rises and how the ice is behaving in response to the global warming. RESEARCHERS ARE EXCITED ABOUT RICH DATASET OF LAKES RELATED ARTICLES Researchers Reveal: The Egyptian Civilization Is Thousands Of Years Older Than ThoughtRussian Researchers Reveal A Mummified Alien Helen Amanda Fricker from Scripps Institute said that it was amazing to think that people did not know that the lake was in existence until just a decade ago.

It was Fricker that had first found sub-glacial Lake Whillans from satellite data back in 2007. She went on to say that it was exciting to be able to see the lakes rich dataset and that the new data is helping them to understand the function of the lakes as a part of the ice-sheet system. The sub-glacial Lake is fed by ice which has a small amount of seawater in it from the ancient marine sediments that are on the lakes seabed. The lake's water drains periodically into the ocean through channels that are connected to the lake, but they do not have energy enough to carry much of the sediment. NEW DATA WILL LEAD TO BETTER UNDERSTANDING OF MECHANICS OF LAKE WHILLANS Researchers have said that the new data should give them a much better understanding of the mechanics and biogeochemistry of Lake Whillans. It was also said that the data is going to help them to improve the current models and tell them more about how the sub-glacial lake systems in Antarctica interact with any ice that is underneath the surface along with the sediments that are found under it. In January 2013 three different papers analyzed the studies following the WISSARD project having managed to drill successfully down into the sheet of ice to reach subglacial Lake Whillans, to get some samples of sediment along with water samples that had been isolated from any direct contact with the atmosphere of the Earth for many thousands of years.

The Geology and Earth and Planetary Science Letters journal published two of the more interesting of the papers. Alexander Michaud from the Montana State University and the lead author said that data had come from the 15-inch long core lake sediment so that the water chemistry along with the sediment could be characterized. LAKE WATER MOSTLY COMES FROM MELTING ICE AT BASE COVERING LAKE Researchers found that the water in the lake originates mostly from the melting ice at the base of the sheet that covers the sub-glacial lake and that there had been very little contribution from any seawater, trapped under the ice in the sediment during the last inter-glacial period. A second paper had been published by lead author Timothy Hodson from the Northern Illinois University in which he along with colleagues took a look at the core sediment that had been retrieved from the lake with the hope of trying to find out more about the ice sheet and the relationship with the sediments under it and the subglacial hydrology.

Their discovery found that many floods had passed through the lake but that the floods flow was lacking in energy when it came to eroding the extensive drainage channels. The researchers came to the conclusion that the environment underneath Antarctica is similar to that of wetlands in the coastal plain that is found in other parts on the planet. Antarctica of course, broke away from Gondwana around 25 million years ago; around 170 million years ago it had been part of the Gondwana supercontinent before breaking away. Research shows that Antarctica has not always been the very dry and cold region that we know to be covered in sheets of ice. Throughout its long history, it was further to the north and this meant that it experienced a climate that was either tropical or temperate, which would have meant that it had been covered in forest, along with being home to many ancient life forms.

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Earth in 1000 Years

Ice in its varied forms covers as much as 16% of Earth’s surface, including 33% of land areas at the height of the northern winter. Glaciers, sea ice, permafrost, ice sheets and snow play an important role in Earth’s climate. They reflect energy back to space, shape ocean currents, and spawn weather patterns. But there are signs that Earth’s great stores of ice are beginning to melt. To find out where Earth might be headed, scientists are drilling down into the ice, and scouring ancient sea beds, for evidence of past climate change. What are they learning about the fate of our planet, a thousand years into the future and even beyond? 30,000 years ago, Earth began a relentless descent into winter, Glaciers pushed into what were temperate zones. Ice spread beyond polar seas. New layers of ice accumulated on the vast frozen plateau of Greenland.

At three kilometers thick, Greenland’s ice sheet is a monumental formation built over successive ice ages and millions of years. It’s so heavy that it has pushed much of the island down below sea level. And yet, today, scientists have begun to wonder how resilient this ice sheet really is. Average global temperatures have risen about one degree Celsius since the industrial revolution. They could go up another degree by the end of this century. If Greenland’s ice sheet were to melt, sea levels would rise by over seven meters. That would destroy or threaten the homes and livelihoods of up to a quarter of the world’s population. These elevation maps show some of the areas at risk. Black and red are less than 10 meters above current sea level. The Southeastern United States, including Florida, And Louisiana.

Bangladesh. The Persian Gulf. Parts of Southeast Asia and China. That’s just the beginning. With so much at stake, scientists are monitoring Earth’s frozen zones, with satellites, radar flights, and expeditions to drill deep into ice sheets. And they are reconstructing past climates, looking for clues to where Earth might now be headed, not just centuries, but thousands of years in the future. Periods of melting and freezing, it turns out, are central events in our planet’s history. That’s been born out by evidence ranging from geological traces of past sea levels, the distribution of fossils, chemical traces that correspond to ocean temperatures, and more. Going back over two billion years, earth has experienced five major glacial or ice ages. The first, called the Huronian, has been linked to the rise of photosynthesis in primitive organisms. They began to take in carbon dioxide, an important greenhouse gas. That decreased the amount of solar energy trapped by the atmosphere, sending Earth into a deep freeze.

The second major ice age began 580 million years ago. It was so severe, it’s often referred to as “snowball earth.” The Andean-Saharan and the Karoo ice ages began 460 and 360 million years ago. Finally, there’s the Quaternary, from 2.6 million years ago to the present. Periods of cooling and warming have been spurred by a range of interlocking factors: volcanic events, the evolution of plants and animals, patterns of ocean circulation, the movement of continents. The world as we know it was beginning to take shape in the period from 90 to 50 million years ago. The continents were moving toward their present positions. The Americas separated from Europe and Africa. India headed toward a merger with Asia. The world was getting warmer.

Temperatures spiked roughly 55 million years ago, going up about 5 degrees Celsius in just a few thousand years. CO2 levels rose to about 1000 parts per million, compared to 280 in pre-industrial times, and 390 today. But the stage was set for a major cool down. The configuration of landmasses had cut the Arctic off from the wider oceans. That allowed a layer of fresh water to settle over it, and a sea plant called Azolla to spread widely. In a year, it can soak up as much as 6 tons of CO2 per acre. Plowing into Asia, the Indian subcontinent caused the mighty Himalayan Mountains to rise up. In a process called weathering, rainfall interacting with exposed rock began to draw more CO2 from the atmosphere, washing it into the sea. Temperatures steadily dropped.

By around 33 million years ago, South America had separated from Antarctica. Currents swirling around the continent isolated it from warm waters to the north. An ice sheet formed. In time, with temperatures and CO2 levels continuing to fall, the door was open for a more subtle climate driver. It was first described by the 19th century Serbian scientist, Milutin Milankovic. He saw that periodic variations in Earth’s rotational motion altered the amount of solar radiation striking the poles. In combination, every 100,000 years or so, these variations have sent earth into a period of cool temperatures and spreading ice. Each glacial period was followed by an interglacial period in which temperatures rose and the ice retreated. The Milankovic cycles are not strong enough by themselves to cause the shift.

What they do is get the ball rolling. A decrease in solar energy hitting the Arctic allows sea ice to form in winter and remain over summer, then to expand its reach the following year. The ice reflects more solar energy back to space. A colder ocean stores more CO2, which further dampens the greenhouse effect. Conversely, when ocean temperatures rise, more CO2 escapes into the atmosphere, where it traps more solar energy. With so many factors at play, each swing of the climate pendulum has produced its own unique conditions. Take, for example, the last interglacial, known as the Eemian, from 130 to 115,000 years ago. This happened at a time when CO2 was at preindustrial levels, and global temperatures had risen only modestly. But with higher solar energy striking the north, temperatures rose dramatically in the Arctic. The effect was amplified by the lower reflectivity of ice-free seas and spreading northern forests.

There is still uncertainty about how much these changes affected sea levels. Estimates range from a 5 to 9 meters, levels that would be catastrophic today. That’s one reason scientists today are intensively monitoring Earth’s frozen zones, including the ice sheet that covers Greenland. Satellite radar shows the flow of ice from the interior of the island and into glaciers. In the eastern part of the island, glaciers push slowly through complex coastal terrain. In areas of higher snowfall in the northwest and west, the ice speeds up by a factor 10. The landscape channels the ice into many small glaciers that flow straight down to the sea. In the distant past, the center of the island may have been drained by a giant canyon, recently discovered. Scientists found that it’s 550 kilometers long and up to 800 meters deep.

It leads from Greenland’s interior to one of today’s most volatile glaciers. This is the Petermann Glacier in Northwest Greenland. Amid unusually warm summer temperatures in 2012, satellites tracked a giant iceberg as it broke off and moved down the glacier’s outlet channel. At about 31 square kilometers, this island of ice stayed together as it floated along. After two months, it finally began to fragment. The Jakobshavn glacier on Greenland’s west coast flows toward the sea at a rapid rate of 20 to 40 meters per day. At the ice front, where the glacier meets the sea, Jakobshavn has been retreating as it dumps more and more ice into the ocean. You can see it in this map. In 1851, the front was down here. Now it’s 50 kilometers up. One reason, scientists say, is that water seeping down into its base is acting like a lubricant.

Another is that as the glacier thins, it’s more likely to break off, or calve, when it interacts with warmer ocean waters. Scientists are tracking the overall rate of ice loss with the Grace Satellite. They found that from 2003 to 2009, Greenland lost about a trillion tons, mostly along its coastlines. This number mirrors ice loss in the Arctic as a whole. By 2012, summer sea ice coverage had fallen to a little more than half of what it was in the year 1980. While the ice rebounded in 2013, the coverage was still well below the average of the last three decades. Analyzing global data from Grace, one study reports that Earth lost about 4,000 cubic kilometers of ice in the decade leading up to 2012. Sea levels around the world are now expected to rise about a meter by the end of the century. What will happen beyond that? To gauge the resilience of Greenland’s great ice sheet, scientists mounted one of the most intensive glacial drilling projects to date, the North Greenland Eemian Ice Drilling Project, or NEEM. The ice samples they obtained from the height of Eemian warming told a surprising story.

If you were a visitor to Northern Greenland in those times, you would have stood on ice over two kilometers thick. Temperatures were warmer than today by about 8 degrees Celsius. And yet, the ice had receded by only about 25%, a relatively modest amount. That has shifted the focus to Earth’s other, much larger ice sheet, on the continent of Antarctica. Antarctica contains 90% of all the ice, and 70% of all the fresh water on the Earth. Scientists are asking: how dynamic are its ice sheets? How sensitive are they to melting? Data from Grace and other satellites shows that this frozen continent overall has lately been losing as much ice as it gains. The vast plateau of Antarctic ice is one of the driest deserts on Earth. What little snow falls, remains, adding to the continent’s mass. You can see evidence of this in the snow and ice that piles up at the South Pole research station. This geodesic dome was built in the 1970s.

By the time it was decommissioned in 2009, the entrance was nearly buried. With a thickness of up to 4 kilometers, the ice on which this outpost sits will not melt easily. That’s true in part because of the landmass below it, captured in an extraordinary radar image. The eastern part of the continent, the far side of the image, is a stable foundation of continental crust. In contrast, the western side dips as much as 2500 meters below present day sea level. Along the Amundsen Sea Coast, the ice is disappearing at an accelerating rate. Inland ice streams are moving toward the ocean at at least 100 meters per year. They end up in floating ice shelves that extend hundreds of miles into the ocean. This region is the greatest source of uncertainty about global sea level projections. When ice shelves like this grow, they become prone to fracturing. A giant crack, for example, recently appeared in the Pine Island Glacier. Within two years, a 720 square kilometer iceberg had broken off.

But the scientists are more concerned about what’s happening below the surface. In recent times, the Southern ocean that swirls around the continent has been getting warmer, at the rate of .2 degrees Celsius per decade. That has affected ice shelves like Pine Island by melting them from below. In a comprehensive survey of the continent, scientists concluded that this process was responsible for 55 percent of the mass lost from ice shelves between 2003 and 2008. It’s also been blamed for one of the more puzzling twists in the story of climate change, the spread of sea ice all around Antarctica. One possibility is that ramped up winds, circling the pole, are pushing the ice into thicker, more resilient formations. Another is that the melting of ice shelves has spread a layer of cold, fresh water over coastal seas, which readily freezes.

A team of researchers has come to the Pine Island Glacier to try to monitor the melting in real time. After five years of preparation, they drilled through 500 meters of ice to begin measuring ice volume, temperature, salinity, and flow. In some places, they found melt rates of about 6 centimeters per day, or about 22 meters in a year. Because ice shelves hold back inland glaciers, the melting could trigger larger changes. That’s likely what happened to the Larsen ice shelf on the Antarctic Peninsula in the year 2002. It’s thought to have been stable since the last interglacial. Warmer ocean waters had been eating away at Larsen’s underside. By early February of 2002, the shelf began to splinter into countless small icebergs. By March 7th, when this picture was taken, it had completely collapsed, forming a vast slush that drifted out to sea. Without the shelf’s buttressing effect, a series of nearby glaciers picked up speed, dumping an additional 27 cubic kilometers of ice into the ocean per year.

Evidence from the last interglacial, the Eemian, brings an ominous warning of what could lie ahead. It’s based on the height of ancient coral reefs, which grow to a depth relative to the sea level above them. Based on reefs along the Australian coast, a recent study published in the journal Nature showed that sea levels remained stable for most of the Eemian, at 3-4 meters above those of today. But the authors found that in the last few thousand years of the period, starting around 118,000 years ago, sea levels suddenly shot up to 9 meters above today. The authors concluded, in their words, that “a critical ice sheet stability threshold was crossed, resulting in the catastrophic collapse of polar ice sheets.” Looking ahead, uncertainties about the future of our climate abound. According to one study, the long cool down to the next glacial period is due to start in the next 1500 years or so, based on the timing of Milankovic cycles. But for this actually to happen, the study says, enough new ice would have to form to get the ball rolling. CO2 would have to retreat to below pre-industrial levels.

Instead, it appears that a warming climate is becoming a fact of life. The danger is that if the melting gains a momentum of its own, even reducing CO2 emissions may not be enough to stop it. The still unfolding story of Earth’s past tells us about the mechanisms that can shape our climate. But it’s the unique conditions of our time that will determine sea levels, ice coverage, and temperatures. What’s at stake in the coming centuries is the world we know, the one that has nurtured and sustained us. The Earth itself will go on, ever changing on short and long time scales, a dynamic living planet 1.