Posts Tagged ‘Antarctic’
Wing foot pteropod
The shells of some marine snails in the seas around Antarctica are dissolving as the water becomes more acidic, threatening the food chain, said a study published in the journal Nature Geoscience…
Oceans soak up about a quarter of the carbon dioxide released into the atmosphere each year and as CO2 levels in the atmosphere increase from burning fossil fuels, so do ocean levels, making seas more acidic.
Ocean acidification is one of the effects of climate change and threatens coral reefs, marine ecosystems and wildlife.
The shell of the pteropod sea snail in the Southern Ocean was severely dissolved by more acidic surface water, the researchers from the British Antarctic Survey, Royal Netherlands Institute for Sea Research…NOAA and other institutions found.
And although the snails did not necessarily die, it increased their vulnerability to predators and infection which could affect other parts of the food chain.
“The corrosive properties of the water caused shells of live animals to be severely dissolved and this demonstrates how vulnerable pteropods are,” said lead author Nina Bednaršek, from the NOAA.
…Until now, there has been little evidence of the impact of ocean acidification on such live organisms in their natural environment and the study supports predictions that acidification could have a significant effect on marine ecosystems…
Climate models forecast more intense winds in the Southern Ocean this century if CO2 continues to increase, which will make the mixing of deep water with more acidic surface waters more frequent, the study said.
Since the start of the industrial revolution, the acidity of surface ocean waters has increased by 30 percent, according to NOAA research.
The authors of the study predict surface waters could be 150 % more acidic by the end of this century.
Keep messing with my scungilli and I’m getting really pissed off!
The Greenland and Antarctic ice sheets are losing mass at an accelerating pace, according to a new study. The findings of the study – the longest to date of changes in polar ice sheet mass – suggest these ice sheets are overtaking ice loss from Earth’s mountain glaciers and ice caps to become the dominant contributor to global sea level rise, much sooner than model forecasts have predicted…
The nearly 20-year study reveals that in 2006, a year in which comparable results for mass loss in mountain glaciers and ice caps are available from a separate study conducted using other methods, the Greenland and Antarctic ice sheets lost a combined mass of 475 gigatonnes a year on average. That’s enough to raise global sea level by an average of 1.3 millimeters (.05 inches) a year. (A gigatonne is one billion metric tons, or more than 2.2 trillion pounds.) Ice sheets are defined as being larger than 50,000 square kilometers, or 20,000 square miles, and only exist in Greenland and Antarctica while ice caps are areas smaller than 50,000 square km.
The pace at which the polar ice sheets are losing mass was found to be accelerating rapidly. Each year over the course of the study, the two ice sheets lost a combined average of 36.3 gigatonnes more than they did the year before. In comparison, the 2006 study of mountain glaciers and ice caps estimated their loss at 402 gigatonnes a year on average, with a year-over-year acceleration rate three times smaller than that of the ice sheets.
“That ice sheets will dominate future sea level rise is not surprising — they hold a lot more ice mass than mountain glaciers,” said lead author Eric Rignot, of NASA’s Jet Propulsion Laboratory, Pasadena, California, and the University of California, Irvine. “What is surprising is this increased contribution by the ice sheets is already happening. If present trends continue, sea level is likely to be significantly higher than levels projected by the United Nations Intergovernmental Panel on Climate Change in 2007. Our study helps reduce uncertainties in near-term projections of sea level rise.”
Rignot’s team combined nearly two decades (1992-2009) of monthly satellite measurements with advanced regional atmospheric climate model data to examine changes in ice sheet mass and trends in acceleration of ice loss…
The team found that for each year over the 18-year study, the Greenland ice sheet lost mass faster than it did the year before, by an average of 21.9 gigatonnes a year. In Antarctica, the year-over-year speedup in ice mass lost averaged 14.5 gigatonnes…
While this provides one indication of the potential contribution ice sheets could make to sea level in the coming century, the authors caution that considerable uncertainties remain in estimating future ice loss acceleration.
The inherent conservatism of bona fide scientists once again accounts for the element of a “surprising” rate of melting. Not that it means much to pundits or politicians committed to fossil fuel funding. Or, sadly, a populace in general that’s hardly past WW2 in terms of general understanding of science.
The flywheel effect is so strong that even when people are pushed far enough, no longer being able to ignore reality – it will take generations to begin to halt and then reverse the effects of global warming.
Good thing there’s no permafrost in the United States, eh?
Up to two-thirds of Earth’s permafrost likely will disappear by 2200 as a result of warming temperatures, unleashing vast quantities of carbon into the atmosphere, says a new study by the University of Colorado Boulder’s Cooperative Institute for Research in Environmental Sciences.
The carbon resides in permanently frozen ground that is beginning to thaw in high latitudes from warming temperatures, which will impact not only the climate but also international strategies to reduce fossil fuel emissions, said CU-Boulder’s Kevin Schaefer, lead study author. “If we want to hit a target carbon dioxide concentration, then we have to reduce fossil fuel emissions that much lower than previously thought to account for this additional carbon from the permafrost,” he said. “Otherwise we will end up with a warmer Earth than we want.”
The escaping carbon comes from plant material, primarily roots trapped and frozen in soil during the last glacial period that ended roughly 12,000 years ago, he said. Schaefer, a research associate at CU-Boulder’s National Snow and Ice Data Center, an arm of CIRES, likened the mechanism to storing broccoli in a home freezer. “As long as it stays frozen, it stays stable for many years,” he said. “But if you take it out of the freezer it will thaw out and decay.”
While other studies have shown carbon has begun to leak out of permafrost in Alaska and Siberia, the study by Schaefer and his colleagues is the first to make actual estimates of future carbon release from permafrost…
Schaefer and his team ran multiple Arctic simulations assuming different rates of temperature increases to forecast how much carbon may be released globally from permafrost in the next two centuries. They estimate a release of roughly 190 billion tons of carbon, most of it in the next 100 years…
“The amount we expect to be released by permafrost is equivalent to half of the amount of carbon released since the dawn of the Industrial Age,” said Schaefer. The amount of carbon predicted for release between now and 2200 is about one-fifth of the total amount of carbon in the atmosphere today, according to the study…
Greater reductions in fossil fuel emissions to account for carbon released by the permafrost will be a daunting global challenge, Schaefer said. “The problem is getting more and more difficult all the time,” he said. “It is hard enough to reduce the emissions in any case, but now we have to reduce emissions even more. We think it is important to get that message out now.”
Using importance and science in the same sentence won’t mean much to politicians, pundits – or the pipsqueaks who prance around at the behest of fossil fuel profiteers. And the average consumer isn’t as likely to be impressed by computational analysis as how much their pocketbook is being squeezed for fuel oil and gasoline.
Fortunately, the Oil Patch Boys and their bubbas in the Middle east are doing a reasonably effective job of the last-named activity.
New research indicates the impact of rising CO2 levels in the Earth’s atmosphere will cause unstoppable effects to the climate for at least the next 1000 years, causing researchers to estimate a collapse of the West Antarctic ice sheet by the year 3000, and an eventual rise in the global sea level of at least four metres.
The study…is the first full climate model simulation to make predictions out to 1000 years from now. It is based on best-case, ’zero-emissions’ scenarios constructed by a team of researchers from the Canadian Centre for Climate Modelling and Analysis…and the University of Calgary.
“We created ‘what if’ scenarios,” says Dr. Shawn Marshall, Canada Research Chair in Climate Change and University of Calgary geography professor. “What if we completely stopped using fossil fuels and put no more CO2 in the atmosphere? How long would it then take to reverse current climate change trends and will things first become worse?” The research team explored zero-emissions scenarios beginning in 2010 and in 2100.
The Northern Hemisphere fares better than the south in the computer simulations, with patterns of climate change reversing within the 1000-year timeframe in places like Canada. At the same time parts of North Africa experience desertification as land dries out by up to 30 percent, and ocean warming of up to 5°C off of Antarctica is likely to trigger widespread collapse of the West Antarctic ice sheet, a region the size of the Canadian prairies…
Researchers will next begin to investigate more deeply the impact of atmosphere temperature on ocean temperature to help determine the rate at which West Antarctica could destabilize and how long it may take to fully collapse into the water.
My first response to reading this was, “Cripes! One more excuse for Know-Nothings to Do-Nothing.”
The follow-on to that is that they aren’t going to do anything sensible, responsible, constructive – anyway. Political reactionaries, ethical and social ignoranuses never have responded to science and reason with anything other than fear and scorn. That is what limits their species to the superstitions that bound their comprehension of reality.
Everyone else will continue on with educated politics and the construction of appropriate means to respond to changing circumstances. As we always have done.
Commercial harbors and business centers in Shanghai, Auckland and Vancouver will be altered or relocated. The leaders of Texas will kneel and pray for a miracle while Houston sinks into the Gulf of Mexico.
RTFA for more detail.
An iceberg the size of Luxembourg has broken off from a glacier in Antarctica after being rammed by another giant iceberg, scientists said on Friday, in an event that could affect ocean circulation patterns.
The 2,500 sq km iceberg broke off earlier this month from the Mertz Glacier’s 160 km floating tongue of ice that sticks out into the Southern Ocean…
“The calving itself hasn’t been directly linked to climate change but it is related to the natural processes occurring on the ice sheet,” said Rob Massom, a senior scientist…at the Antarctic Climate and Ecosystems Cooperative Research Center…
Massom said the shearing off of the ice tongue and the presence of the Mertz and B-9B icebergs could affect global ocean circulation.
The area is an important zone for the creation of dense, salty water that is a key driver of global ocean circulation. This is produced in part through the rapid production of sea ice that is continually blown to the west.
“Removal of this tongue of floating ice would reduce the size of that area of open water, which would slow down the rate of salinity input into the ocean and it could slow down this rate of Antarctic bottom water formation,” he said.
He said there was a risk both icebergs would become grounded on banks or shoals in the area, disrupting the creation of the dense, salty water and the amount that sinks to the bottom of the ocean, he said.
Oceans act like a giant flywheel for the planet’s climate by shifting heat around the globe via myriad currents above and below the surface.
There’s not much hope for either climate deniers or the average Western Whoopee Weather Whiner to make sense of this. I’ve given up even on explaining something as relevant – and simple – as El Niño to bloggers/commenters/dolts who think that a large snowstorm on the eastern coast of a nation accounting for 1.5% of the Earth’s surface somehow means there is no global warming.
The rest of you – fortunately – have enough interest in science and natural processes to find this interesting on its own. I thank all six of you.
Three crates of Scotch whisky and two crates of brandy left beneath the floorboards of a hut by the polar explorer Ernest Shackleton in 1909, at the end of a failed expedition to the South Pole, have been unearthed by a team from the Antarctic Heritage Trust.
Al Fastier, who led the team, said the discovery of the brandy was a surprise, according to a news release posted online by the trust. The team had expected to find just two crates of whisky buried under the hut. The trust reported that that ice had cracked some of the crates and formed inside, “which will make the job of extracting the contents very delicate.”
Richard Paterson, a master blender for Whyte & Mackay, which supplied the Shackleton expedition with 25 crates of Mackinlay’s “Rare and Old” whisky, described the unearthing of the bottles as “a gift from the heavens for whisky lovers,” since the recipe for that blend has been lost. “If the contents can be confirmed, safely extracted and analyzed, the original blend may be able to be replicated.”
Mr. Paterson addressed the question of what the whisky might taste like in a post on his blog when the plan to dig it up was first announced, last year:
Whiskies back then — a harder age — were all quite heavy and peaty as that was the style. And depending on the storage conditions, it may still have that heaviness. For example, it may taste the same as it did back then if the cork has stayed in the bottle and kept it airtight.
The trust’s Web site has a detailed history of the failed expedition, as well as this video on its efforts to preserve the hut built as a base for the Shackleton expedition at Cape Royds, Antarctica, in 1908:
I would give my late father’s left whatchamacallit to sip a dram or two of that whisky. The spirit of Earth’s adventure.
Daylife/Reuters Pictures used by permission
East Antarctica’s ice started to melt faster from 2006, which could cause sea levels to rise sooner than anticipated, according to a study by scientists at the University of Texas.
In the study published in Nature’s Geoscience journal, scientists estimated that East Antarctica has been losing ice mass at an average rate of 5 to 109 gigatonnes per year from April 2002 to January 2009, but the rate speeded up from 2006.
The melt rate after 2006 could be even higher, the scientists said.
“The key result is that [we] appear to start seeing a large amount of ice loss in East Antarctica, mostly in the long coastal regions (in Wilkes Land and Victoria Land), since 2006,” Jianli Chen at the university’s centre for space research and one of the study’s authors, told Reuters.
“This, if confirmed, could indicate a state change of East Antarctica, which could pose a large impact on global sea levels in the future,” Chen said…
Climate change is turning Antarctica’s ice into the one of the biggest risks for coming centuries. Even slight melting could drive up sea levels and could affect world’s cities.
Over the several years I have been studying climate change Antarctic ice was thought to be less-affected than the Northern Pole. Now that means and methods have improved, we get to figure out the bad news is universal.
note: at post time, the direct link to the study – in the Reuters article – was broken.
Chinese scientists from the country’s 26th Antarctic expedition are expected to complete the world’s first land cover map of the Antarctica at the end of this year.
It will be the most accurate map of the continent, presenting various land features, they told Xinhua correspondent aboard Xue Long (Snow Dragon) icebreaker in a recent interview…
The map, with the application of high resolution remote sensing technology, will for the first time in the history show the distribution of key features on the continent, including sea ice, snow, blue ice, rocks, soil marshes, lakes and ice crevasse…
The map is also based on 1,073 remote sensing images acquired from the U.S. satellite Land Sat mainly during the austral summer from 1999 to 2002, Cheng Xiao, deputy dean of the College of Global Change and Earth System Science, Beijing Normal University, told Xinhua via email…
The map will provide not only more accurate ground parameters for scientists to forecast global change or global warming with climate system models, but also important data for detection on the change of Antarctica land cover in a long run, Cheng said.
I’ve always been one of those geeks crazy about maps. Looking forward to seeing the final product.
Humpback whale checking out the humans in the neighborhood
Daylife/Reuters Pictures used by permission
Scientists are surprised at how extensively coastal ice in Antarctica and Greenland is thinning, according to a study that could help predict rising sea levels linked to climate change.
Analysis of millions of NASA satellite laser images showed the biggest loss of ice was caused by glaciers speeding up when they flowed into the sea, according to scientists at the British Antarctic Survey (BAS) and Bristol University.
“We were surprised to see such a strong pattern of thinning glaciers across such large areas of coastline — it’s widespread and in some cases thinning extends hundreds of kilometers inland,” said Hamish Pritchard of BAS who led the study…
Among findings, Wednesday’s study said 81 of 111 fast-moving glaciers in Greenland were thinning at twice the rate of slow-flowing ice at the same altitude.
“Dynamic thinning of Greenland and Antarctic ice-sheet margins is more sensitive, pervasive, enduring and important than previously realized,” they wrote. “Dynamic thinning” means loss of ice due to a faster flow.
There are a number of variables in the dynamism – all happening faster than anyone expected.