(Press-News.org) On Friday, Jan. 28 in Antarctica, a research team investigating the last 100,000 years of Earth's climate history reached an important milestone completing the main ice core to a depth of 3,331 meters (10,928 feet) at West Antarctic Ice Sheet Divide (WAIS). The project will be completed over the next two years with some additional coring and borehole logging to obtain additional information and samples of the ice for the study of the climate record contained in the core.
As part of the project, begun six years ago, the team, funded by the National Science Foundation (NSF), has been drilling deep into the ice at the WAIS Divide site and recovering and analyzing ice cores for clues about how changes in the concentration of greenhouse gases in the atmosphere have influenced the Earth's climate over time.
Friday's milestone was reached at a depth of 3,331 meters--about two miles deep--creating the deepest ice core ever drilled by the U.S. and the second deepest ice core ever drilled by any group, second only to the ice core drilled at Russia's Vostok Station as part of a joint French/U.S./Russian collaboration in the 1990s.
"By improving our understanding of how natural changes in greenhouse gas influenced climate in the past, the science community will be able to do a better job of predicting future climate changes caused by the emissions of greenhouse gases by human activity," said Kendrick Taylor, chief scientist for the WAIS Divide Ice Core Project.
The drilling site is about 966 kilometers (600 miles) from the South Pole, at an ice divide (which is analogous to a watershed divide) in West Antarctica, where the ice is flowing out to the sea in opposing directions.
"This location was selected because it is the best place on the planet to determine how greenhouse gases have changed during the last 100,000 years" said Taylor. Since it began, the WAIS Divide Ice Core Project has continuously collected ice from the surface down to a depth of 3,331 meters. The ice at this depth fell as snow about 100,000 years ago. The high annual snowfall at the site enables individual annual layers of snowfall to be identified and counted (much like counting tree rings) back to about 40,000 years. Below that, the layers become too compressed to allow annual layers to be resolved. Scientists hope for at least decadal resolution to this point, sufficient for the science goals to be achieved.
The ice cores are 13-centimeter (5-inch) diameter cylinders of ice collected from deep in the ice sheet. Over time, the ice has formed when snow was compacted at the surface by subsequent snowfall. The compacted snow contains dust, chemicals and atmospheric gases, which are trapped in the ice.
The dust and other impurities in the ice are indicators of past climate, and the gas contained in air bubbles is a sample of the ancient atmosphere. The deeper the ice, the further back in time measurements can be made.
In addition to measuring what the atmospheric concentrations of carbon dioxide, methane and other gases were in the past, the research team can also determine what the surface air temperature was in the past by studying changes in the isotopic composition of the water that makes up the ice. The past atmospheric concentrations of the gases krypton and xenon are used to determine what the average temperature of the ocean was in the past.
The 13-centimeter diameter 3,331-meter-long ice core is cut into 1 meter (3 feet)-long pieces of ice and sent by ship and refrigerated truck to the NSF National Ice Core Laboratory in Denver. The ice is cut into smaller samples and sent to 27 investigators around the U.S., who make the measurements.
"Previous ice cores have shown that the current level of greenhouse gases is greater now than at any time during the last 650,000 years, and that concentrations today are increasing at the fastest rate," said Taylor. "This increase is caused by human activity and is forcing the climate into a configuration that no human has ever experienced."
The WAIS Divide Ice Core Project is specifically investigating the small timing offsets between past changes in the atmospheric concentration of greenhouse gases and changes in temperature. By understanding these timing offsets, the research team can determine the role that changes in ocean circulation had in the release of carbon dioxide from the ocean and how an increase in carbon dioxide in the atmosphere warms the planet.
The drilling ceased 100 meters (328 feet) above the contact between the ice and the underlying rock, to avoid contaminating a possible water layer at the ice-rock contact. The basal water system may consist of water-saturated, ground-up rock, and has not been exposed to the earth's surface for millions of years. It may harbor a unique and pristine biological environment that the U.S. Antarctic Program does not wish to contaminate.
The core taken by the WAIS Ice Core Drilling Project is crucial for fine-tuning the researchers' understanding of how the oceans, atmosphere and climate interact during climate changes. A Danish-led team recovered an ice core from Greenland this past summer with similar time resolution to the WAIS Divide record. The two cores provide an opportunity to compare the response of the northern and southern hemispheres to climate changes. The Greenland ice core cannot be used to study changes in the atmospheric concentration of carbon dioxide because there is too much dust in the Greenland ice, which decomposes and releases non-atmospheric carbon dioxide into the ice.
NSF's Office of Polar Programs funds this research, primarily through its Antarctic Glaciology Program.
"We still have two more field seasons of work to complete the project, and reaching this goal should allow us to complete the project on schedule," said Julie Palais, program director. "In addition, we are hoping to get as long a record as possible from this site, and getting all of the ice we planned on this year will allow the science community to do the work that they are funded to do. Drilling the ice core is just the first step in the process, albeit a very important one."
INFORMATION:
Some additional funding is provided by NSF's Antarctic Organisms and Ecosystems Program. Logistical and drilling support is from NSF's Divisions of Antarctic Infrastructure and Logistics and Antarctic Science.
The lead institution is the Desert Research Institute, Nevada System of Higher Education. Science coordination is provided by the University of New Hampshire.
Ice cores yield rich history of climate change
Research project completes drilling for the year, reaching 2 miles below West Antarctic Ice Sheet
2011-02-03
ELSE PRESS RELEASES FROM THIS DATE:
Laser welding in the right light
2011-02-03
It's a quick process, generates almost no waste and is extremely precise: within a few seconds, a laser beam has welded the casing and speedometer cover together – without any screws, clamps or glues whatsoever. The result is a perfect weld seam scarcely visible to the naked eye. There are no sparks or particles flying through the air during welding. What's more: the resulting heat is confined to a minimal area. This protects the material. Many industries have now turned to welding plastics with a laser.
Still, the technology has its limits; when it comes to fusing two ...
UMD advance lights possible path to creating next-gen computer chips
2011-02-03
COLLEGE PARK, Md. - University of Maryland researchers have made a breakthrough in the use of visible light for making tiny integrated circuits. Though their advance is probably at least a decade from commercial use, they say it could one day make it possible for companies like Intel to continue their decades long tread of making ever smaller, faster, and cheaper computer chips.
For some 50 years, the integrated circuits, or chips, that are at the heart of computers, smart phones, and other high-tech devices have been created through a technique known as photolithography, ...
When a blockbuster becomes lackluster: Not all movie-watching experiences are created equal
2011-02-03
MANHATTAN, KAN. -- When you sit down to watch a new flick, whether you enjoy the movie may depend on the person sitting next to you, according to research from a Kansas State University professor. It's especially true if you are awkwardly watching a movie's steamy love scene with your parents.
"We know that most of the time people enjoy watching movies -- that's why they do it," said Richard Harris, K-State professor of psychology. "But sometimes we watch a movie that isn't what we describe as 'enjoyable.' For whatever reason, the experience is uncomfortable emotionally ...
Drugs warning -- check the label
2011-02-03
A new study highlights inconsistencies in black box warnings - medication-related safety warnings on a drug's label - and argues for a more transparent and systematic approach to ensure these warnings are consistent across all drugs within a same category, and any additions to warnings, on the back of a drug withdrawal for example, are done within a reasonable and uniform time period. The work by Orestis Panagiotou and John Ioannidis and colleagues from the University of Ioannina School of Medicine in Greece and Stanford University School of Medicine in the USA is published ...
Generic drug may improve the effectiveness of cancer nanotherapies
2011-02-03
Low doses of an inexpensive, FDA-approved hypertension medication may improve the results of nanotherapeutic approaches to cancer treatment. In a report in the early edition of Proceedings of the National Academy of Sciences, Massachusetts General Hospital (MGH) investigators describe experiments showing that the generic drug losartan, by modifying the network of collagen fibers that characterizes most solid tumors, improved the effectiveness of two nanotherapeutics against several types of cancer.
"By 'normalizing' the abnormal extracellular matrix of tumors, which ...
Lampreys give clues to evolution of immune system
2011-02-03
Biologists have discovered that primitive, predatory lampreys have structures within their gills that play the same role as the thymus, the organ where immune cells called T cells develop in mammals, birds and fish.
The finding suggests that in vertebrate evolution, having two separate organs for immune cell development -- the bone marrow for B cells and the thymus for T cells -- may have preceded the appearance of the particular features that mark those cells, such as antibodies and T cell receptors.
The results will be published Feb. 3 by the journal Nature.
The ...
Extreme X-ray pulses create unique image of intact virus
2011-02-03
They are entirely too small to be seen even with the most powerful microscope. But now an international research team has managed to capture an image of an intact virus and a membrane structure from a photosynthetic bacterium with the aid of extremely intensive and ultra-short x-ray pulses from the world's first free electron laser. This new advance in structural biology is being published today in two articles in the journal Nature.
The findings for the two studies pave the way for studies of biological structures at the molecular level, including viruses, individual ...
Effective treatment of Lyme-disease-related arthritis depends on proper diagnosis
2011-02-03
– Early, correct diagnosis is the best way to prevent the development of Lyme arthritis in individuals with the tick-borne illness, according to a paper published in the Journal of the American Academy of Orthopaedic Surgeons (JAAOS). In patients who do develop the condition, most cases can be treated successfully with antibiotics, the review found.
"Lyme arthritis occurs commonly in patients with Lyme disease and should be considered when evaluating patients with joint complaints and who live in areas where the disease occurs," said study author Aristides Cruz, MD, ...
ESA members take part in National Bed Bug Summit
2011-02-03
Fifteen members of the Entomological Society of America (ESA) gave presentations at the "Second Annual National Bed Bug Summit: Advancing Towards Solutions to the Bed Bug Problem," held by the U.S. Environmental Protection Agency (EPA) in Washington, DC, February 2, 2011.
The meeting focused on what is being done to combat bed bugs, the importance of educating consumers, improvements in prevention and control techniques, controlling bed bugs in schools and public housing, and on the state of bed bug knowledge and futue research needs.
"Many health departments are overwhelmed ...
Sideline test accurately detects athletes' concussions in minutes, Penn study shows
2011-02-03
PHILADELPHIA – A simple test performed at the sideline of sporting events can accurately detect concussions in athletes, according to study by researchers at the University of Pennsylvania School of Medicine. Current sideline tests can leave a wide amount a brain function untested following concussion. Penn researchers showed that this simple test was superior to current methods and accurately and reliably identified athletes with head trauma. The study appears online now in Neurology.
The one-minute test involves the athlete reading single digit numbers displayed on index-sized ...
LAST 30 PRESS RELEASES:
Scientists unlock secrets behind flowering of the king of fruits
Texas A&M researchers illuminate the mysteries of icy ocean worlds
Prosthetic material could help reduce infections from intravenous catheters
Can the heart heal itself? New study says it can
Microscopic discovery in cancer cells could have a big impact
Rice researchers take ‘significant leap forward’ with quantum simulation of molecular electron transfer
Breakthrough new material brings affordable, sustainable future within grasp
How everyday activities inside your home can generate energy
Inequality weakens local governance and public satisfaction, study finds
Uncovering key molecular factors behind malaria’s deadliest strain
UC Davis researchers help decode the cause of aggressive breast cancer in women of color
Researchers discovered replication hubs for human norovirus
SNU researchers develop the world’s most sensitive flexible strain sensor
Tiny, wireless antennas use light to monitor cellular communication
Neutrality has played a pivotal, but under-examined, role in international relations, new research shows
Study reveals right whales live 130 years — or more
Researchers reveal how human eyelashes promote water drainage
Pollinators most vulnerable to rising global temperatures are flies, study shows
DFG to fund eight new research units
Modern AI systems have achieved Turing's vision, but not exactly how he hoped
Quantum walk computing unlocks new potential in quantum science and technology
Construction materials and household items are a part of a long-term carbon sink called the “technosphere”
First demonstration of quantum teleportation over busy Internet cables
Disparities and gaps in breast cancer screening for women ages 40 to 49
US tobacco 21 policies and potential mortality reductions by state
AI-driven approach reveals hidden hazards of chemical mixtures in rivers
Older age linked to increased complications after breast reconstruction
ESA and NASA satellites deliver first joint picture of Greenland Ice Sheet melting
Early detection model for pancreatic necrosis improves patient outcomes
Poor vascular health accelerates brain ageing
[Press-News.org] Ice cores yield rich history of climate changeResearch project completes drilling for the year, reaching 2 miles below West Antarctic Ice Sheet