As Australians become increasingly alert to the importance of using water wisely in the home, CSIRO researchers have found a way to use a third less water when you shower – by adding air.
The scientists have developed a simple 'air shower' device which, when fitted into existing showerheads, fills the water droplets with a tiny bubble of air. The result is the shower feels just as wet and just as strong as before, but now uses much less water.
The researchers, from CSIRO Manufacturing Materials Technology in Melbourne, say the device increases the volume of the shower stream while reducing the amount of water used by about 30 per cent.
Given the average Australian household uses about 200,000 litres of water a year, and showers account for nearly a third of this, the 'air shower' could help the average household save about 15,000-20,000 litres a year. If you extend this across the population, that is an annual saving of more than 45,000 Olympic-sized swimming pools.
The Aerated Showerhead creates the sensation of having a full and steady stream of water even though the water is now more like a wet shell around a bubble of air.
While the general concept of using an aerated showerhead to save water is not new, the technology behind the CSIRO's device is novel.
Developed by a team led by Dr Jie Wu, the aeration device is a small nozzle that fits inside a standard showerhead. The nozzle uses a small Venturi tube – a tube for which the diameter varies, creating a difference in pressure and fluid speed. Air is sucked into the Venturi tube as a result of the partial vacuum created, causing air and water to mix, forming tiny bubbles within the water stream.
"The nozzle creates a vacuum that sucks in air and forces it into the water stream," Dr Wu says.
"We make the water droplets in the stream hollow and the bubbles expand the volume of the shower stream."
Small-scale experiments using the aeration device found that people detected no difference in water pressure, sensation, or overall perception of showering.
After almost two years of research and development, CSIRO is ready to take the aerated shower head technology to the commercialisation stage.
"We have very promising results on the aerated showerhead's water-saving potential. Now we are looking for commercialisation partners who will be involved in the development needed to turn the technology into a marketable device," Dr Wu says.
He expects the nozzle would cost less than AUD$20 and could be installed by householders.
Contact: Dr. Dilip Manuel
Dilip.Manuel@csiro.au
61-392-526-083
CSIRO Australia
Thursday, November 09, 2006
Saturday, September 23, 2006
Iowa State corn/soy plastics to be made into hog feeders
Larock, a University Professor of chemistry at Iowa State University, found the thin, square piece he was looking for and smacked it against his hand. This one is made from soybean oil reinforced with glass fibers, he said. And it's the kind of tough bioplastic he and his industrial collaborators will use to develop, test and manufacture new hog feeders.
Richard Larock displays some of the plastics he has made from corn, soybean and other bio-based oils. Larock said his research project is about as Iowa as you can get. The state, after all, is the country's leading producer of corn, soybeans and pork.
The project is partially supported by a grant of $96,000 from the Grow Iowa Values Fund, a state economic development program. Larock is working with AgVantage Inc., a Rockford, Ill., company with manufacturing facilities in Iowa, and R3 Composites, a Muscatine manufacturer.
Larock has invented and patented a process for producing various bioplastics from inexpensive natural oils, which make up 40 percent to 80 percent of the plastics. Larock said the plastics have excellent thermal and mechanical properties and are very good at dampening noises and vibrations. They're also very good at returning to their original shapes when they're heated.
And so Larock is optimistic about the future of bioplastics in commercial applications: "This project should create new technology and jobs, expand opportunities for bio-based industries and agricultural suppliers, decrease our dependence on oil, strengthen the agricultural economy of Iowa, utilize ISU patented technology, provide new markets for farmers and marry new agricultural product development with sophisticated manufacturing skills and the knowledge to commercialize these projects," he wrote in a summary of the hog feeder project.
Ron Hagemann, a principal with AgVantage, said designs for a bioplastic hog feeder have been drawn up. The designs include radio frequency identification technology that can monitor and record the feeding habits of individual hogs. Molds for the high-tech feeders should be completed later this year and prototypes should be ready for testing in a hog building next spring. If all goes well, he said a product should be ready for commercialization by the end of next year.
Hagemann said the feeders' biggest advantage in the marketplace will be material costs. Corn and soybean oils are significantly cheaper than petrochemicals. And that's particularly true when oil prices are high.
Hagemann said he expects this project to be a very good test of Larock's plastics.
Hogs, after all, aren't known for being gentle with their feeders.
"I've told Richard that if we can do this, it's all downhill from here," Hagemann said.
But Larock isn't stopping with the feeder project. He's looking at adding other low-cost agricultural ingredients to his bioplastics. He's now studying whether distillers dried grains, a co-product of ethanol production that's sold as animal feed, can add strength to his bioplastics.
Contact: Richard Larock
larock@iastate.edu
515-294-4660
Iowa State University
Richard Larock displays some of the plastics he has made from corn, soybean and other bio-based oils. Larock said his research project is about as Iowa as you can get. The state, after all, is the country's leading producer of corn, soybeans and pork.
The project is partially supported by a grant of $96,000 from the Grow Iowa Values Fund, a state economic development program. Larock is working with AgVantage Inc., a Rockford, Ill., company with manufacturing facilities in Iowa, and R3 Composites, a Muscatine manufacturer.
Larock has invented and patented a process for producing various bioplastics from inexpensive natural oils, which make up 40 percent to 80 percent of the plastics. Larock said the plastics have excellent thermal and mechanical properties and are very good at dampening noises and vibrations. They're also very good at returning to their original shapes when they're heated.
And so Larock is optimistic about the future of bioplastics in commercial applications: "This project should create new technology and jobs, expand opportunities for bio-based industries and agricultural suppliers, decrease our dependence on oil, strengthen the agricultural economy of Iowa, utilize ISU patented technology, provide new markets for farmers and marry new agricultural product development with sophisticated manufacturing skills and the knowledge to commercialize these projects," he wrote in a summary of the hog feeder project.
Ron Hagemann, a principal with AgVantage, said designs for a bioplastic hog feeder have been drawn up. The designs include radio frequency identification technology that can monitor and record the feeding habits of individual hogs. Molds for the high-tech feeders should be completed later this year and prototypes should be ready for testing in a hog building next spring. If all goes well, he said a product should be ready for commercialization by the end of next year.
Hagemann said the feeders' biggest advantage in the marketplace will be material costs. Corn and soybean oils are significantly cheaper than petrochemicals. And that's particularly true when oil prices are high.
Hagemann said he expects this project to be a very good test of Larock's plastics.
Hogs, after all, aren't known for being gentle with their feeders.
"I've told Richard that if we can do this, it's all downhill from here," Hagemann said.
But Larock isn't stopping with the feeder project. He's looking at adding other low-cost agricultural ingredients to his bioplastics. He's now studying whether distillers dried grains, a co-product of ethanol production that's sold as animal feed, can add strength to his bioplastics.
Contact: Richard Larock
larock@iastate.edu
515-294-4660
Iowa State University
Scientists develop technology for roll-up laptop screens
New ‘morphing’ structures have multiple applications
Scientists at the University of Cambridge have developed a range of unique, shape-changing structures, which can be used as roll-up display screens (such as laptop screens), re-usable packaging, roll-up keyboards and self-erecting, temporary habitats.
These structures, also known as ‘morphing’ structures, afford multiple configurations without the need of complex parts or sophisticated manufacturing. Dr Keith Seffen, from the Department of Engineering, has developed the structures and is currently exploring various applications for their ingenious behaviour with co-worker Dr Simon Guest and graduate student Alex Norman.
Dr Seffen said, “They offer substantial shape-changing capabilities whilst preserving structural integrity. They are simply made and their operation does not rely upon advanced materials. They afford compact, inexpensive solutions for multifunctional devices, which are required to be lightweight, stiff, but foldable on demand.”
By using an ordinary sheet of metal, Dr Seffen can produce structures with no moving parts but which can be configured between at least two distinct, self-locking and stable forms. For example, an A5-sized flat screen can be snapped into the shape of a tube for compact carriage in a briefcase or pocket.
The operation does not require hinges, latches or locks, and without these extra parts, production times and costs are reduced compared to traditional folding structures.
Genevieve Maul, University of Cambridge Office of Communications, Tel: + 44 (0) 1223 332300, e-mail: Genevieve.Maul@admin.cam.ac.uk
Robert Fender, Cambridge Enterprise Tel: + 44 (0) 1223 760339 e-mail: robert.fender@enterprise.cam.ac.uk
Scientists at the University of Cambridge have developed a range of unique, shape-changing structures, which can be used as roll-up display screens (such as laptop screens), re-usable packaging, roll-up keyboards and self-erecting, temporary habitats.
These structures, also known as ‘morphing’ structures, afford multiple configurations without the need of complex parts or sophisticated manufacturing. Dr Keith Seffen, from the Department of Engineering, has developed the structures and is currently exploring various applications for their ingenious behaviour with co-worker Dr Simon Guest and graduate student Alex Norman.
Dr Seffen said, “They offer substantial shape-changing capabilities whilst preserving structural integrity. They are simply made and their operation does not rely upon advanced materials. They afford compact, inexpensive solutions for multifunctional devices, which are required to be lightweight, stiff, but foldable on demand.”
By using an ordinary sheet of metal, Dr Seffen can produce structures with no moving parts but which can be configured between at least two distinct, self-locking and stable forms. For example, an A5-sized flat screen can be snapped into the shape of a tube for compact carriage in a briefcase or pocket.
The operation does not require hinges, latches or locks, and without these extra parts, production times and costs are reduced compared to traditional folding structures.
Genevieve Maul, University of Cambridge Office of Communications, Tel: + 44 (0) 1223 332300, e-mail: Genevieve.Maul@admin.cam.ac.uk
Robert Fender, Cambridge Enterprise Tel: + 44 (0) 1223 760339 e-mail: robert.fender@enterprise.cam.ac.uk
Hope for significant new diabetes treatment in Stanford discovery
STANFORD, Calif. - Certain immune-suppressing drugs, such as those taken by patients who have had organ transplants, greatly increase the risk of developing diabetes. These drugs are known to put a stranglehold on a protein called calcineurin.
So it's not exactly a surprise that Seung Kim, MD, PhD, assistant professor of developmental biology at the Stanford University School of Medicine, chose to study why calcineurin inhibition leads to the disease. What is surprising is just how central calcineurin turns out to be in the health and happiness of the insulin-producing pancreatic beta cells. His findings, to be published in the Sept. 21 issue of Nature, could shake up diabetes research, lead to new classes of diabetes drugs and aid in efforts to develop stem cell treatments for diabetes.
"This work has the potential to be big," said Scott Campbell, PhD, vice president of research for the American Diabetes Association. He said that drugs based on this research could potentially expand the numbers of the few beta cells that remain in diabetics and make those cells perform better. "That would have a major impact on the lives of people with diabetes."
In diabetes, the beta cells produce too little insulin or none at all, which prevents cells of the body from being able to take in sugar after a meal. Sugar accumulates in the blood, damaging the blood vessels, kidneys and eyes. Diabetics are also prone to nerve damage. In the United States, 20.8 million people, or 7 percent of the population, have diabetes.
Knowing the potential link between calcineurin-inhibiting drugs and diabetes, Kim and MD/PhD graduate student Jeremy Heit collaborated with Gerald Crabtree, MD, professor of pathology, in a series of experiments to clarify the connection. They worked with mice that had been bred to produce calcineurin in the pancreas only until they were born. After birth, the pancreas in each mouse stopped producing the protein. By 12 weeks of age, the mice, which had been born with a normal number of beta cells, were severely diabetic.
Squelching calcineurin prevented the beta cells from increasing their numbers as the mice grew - more body mass requires more beta cells to keep blood sugar in check. It also reduced the amount of insulin made by the existing beta cells. What's more, calcineurin was found to regulate 10 genes that already had been associated with diabetes.
"This work has led us and others to think in entirely new ways about diabetes," Heit said. Until now people had identified individual genes or processes that were involved in diabetes. The new findings show that these lines of research are connected through a common regulator in calcineurin.
Heit and Kim used further genetic trickery to bypass calcineurin by artificially activating its protein sidekick, called NFAT. Beta cells lacking calcineurin but with active NFAT behaved normally, multiplying as the mice aged and producing normal amounts of insulin.
The implications of these findings are many:
Drugs that enhance the activity of calcineurin or NFAT could become a new treatment for type-2, or adult-onset diabetes, in which the beta cells don't produce enough insulin.
Drugs that inhibit calcineurin or NFAT could treat diseases in which the beta cells produce too much insulin, such as hypoglycemia or some pancreatic tumors.
Treating isolated beta cells with drugs that enhance calcineurin could make those cells divide, producing more cells for transplantation.
Activating calcineurin could help Kim in his efforts to direct embryonic stem cells to become insulin-producing cells.
Kim, whose work in diabetes includes the development of islet cells, identifying new drug targets and potential stem cell treatments, said the calcineurin findings have wide-ranging implications. "The finding that the calcineurin pathway regulates other pathways in the beta cell makes it highly relevant to many areas of diabetes research," he said.
Campbell said the next step is to verify that the findings in mice also hold true in humans. "This is a step in the right direction and a major leap forward, but now we need to take it into to humans," he said.
Contact: Amy Adams
amyadams@stanford.edu
650-723-3900
Stanford University Medical Center
So it's not exactly a surprise that Seung Kim, MD, PhD, assistant professor of developmental biology at the Stanford University School of Medicine, chose to study why calcineurin inhibition leads to the disease. What is surprising is just how central calcineurin turns out to be in the health and happiness of the insulin-producing pancreatic beta cells. His findings, to be published in the Sept. 21 issue of Nature, could shake up diabetes research, lead to new classes of diabetes drugs and aid in efforts to develop stem cell treatments for diabetes.
"This work has the potential to be big," said Scott Campbell, PhD, vice president of research for the American Diabetes Association. He said that drugs based on this research could potentially expand the numbers of the few beta cells that remain in diabetics and make those cells perform better. "That would have a major impact on the lives of people with diabetes."
In diabetes, the beta cells produce too little insulin or none at all, which prevents cells of the body from being able to take in sugar after a meal. Sugar accumulates in the blood, damaging the blood vessels, kidneys and eyes. Diabetics are also prone to nerve damage. In the United States, 20.8 million people, or 7 percent of the population, have diabetes.
Knowing the potential link between calcineurin-inhibiting drugs and diabetes, Kim and MD/PhD graduate student Jeremy Heit collaborated with Gerald Crabtree, MD, professor of pathology, in a series of experiments to clarify the connection. They worked with mice that had been bred to produce calcineurin in the pancreas only until they were born. After birth, the pancreas in each mouse stopped producing the protein. By 12 weeks of age, the mice, which had been born with a normal number of beta cells, were severely diabetic.
Squelching calcineurin prevented the beta cells from increasing their numbers as the mice grew - more body mass requires more beta cells to keep blood sugar in check. It also reduced the amount of insulin made by the existing beta cells. What's more, calcineurin was found to regulate 10 genes that already had been associated with diabetes.
"This work has led us and others to think in entirely new ways about diabetes," Heit said. Until now people had identified individual genes or processes that were involved in diabetes. The new findings show that these lines of research are connected through a common regulator in calcineurin.
Heit and Kim used further genetic trickery to bypass calcineurin by artificially activating its protein sidekick, called NFAT. Beta cells lacking calcineurin but with active NFAT behaved normally, multiplying as the mice aged and producing normal amounts of insulin.
The implications of these findings are many:
Drugs that enhance the activity of calcineurin or NFAT could become a new treatment for type-2, or adult-onset diabetes, in which the beta cells don't produce enough insulin.
Drugs that inhibit calcineurin or NFAT could treat diseases in which the beta cells produce too much insulin, such as hypoglycemia or some pancreatic tumors.
Treating isolated beta cells with drugs that enhance calcineurin could make those cells divide, producing more cells for transplantation.
Activating calcineurin could help Kim in his efforts to direct embryonic stem cells to become insulin-producing cells.
Kim, whose work in diabetes includes the development of islet cells, identifying new drug targets and potential stem cell treatments, said the calcineurin findings have wide-ranging implications. "The finding that the calcineurin pathway regulates other pathways in the beta cell makes it highly relevant to many areas of diabetes research," he said.
Campbell said the next step is to verify that the findings in mice also hold true in humans. "This is a step in the right direction and a major leap forward, but now we need to take it into to humans," he said.
Contact: Amy Adams
amyadams@stanford.edu
650-723-3900
Stanford University Medical Center
Thursday, September 21, 2006
Climate secrets -- past, present and future revealed with new tool
Made possible through National Science Foundation funding, the XRF Core Scanner will be able to chemically analyze earth and marine sediment cores quickly to find answers to historic climate changes.
VIRGINIA KEY, FLA. A few years ago, chemical analyses of deep sea muds that used a new X-ray technology were able to help explain why the Classic Mayan civilization collapsed more than a thousand years ago. At the University of Miami Rosenstiel School of Marine and Atmospheric Science, a new tool will apply a similar technology to find answers to historic climate changes from earth and marine sediment core samples. The XRF (X-ray Fluorescence) Core Scanner is only the second to make its way to the United States, and the first of this new and improved model made by Avaatech, a company based in the Netherlands.
"From a paleoclimate researcher's perspective, this is a dream come true," said Larry C. Peterson, associate dean of students and the marine geology professor whose lab houses the scanner. "There is a tremendous amount of information about earth history preserved in the chemical composition of sediments deposited on the ocean floor, in lakes, and on land. By measuring the concentration of specific elements in these sediments, the XRF Core Scanner can help us document the history of drastic climate variations and past geological events, giving us more of an idea of the current and future state of our environment."
Made possible through National Science Foundation funding, the XRF Core Scanner will be able to chemically analyze sediment cores quickly and without any physical damage. "Previously, analyses of this type could only be done by a time-consuming process of sampling the cores, then preparing and chemically analyzing the individual samples. The Core Scanner now allows us to determine the complete chemical composition of the same cores without disturbing them, and at a speed and measurement resolution previously unimaginable. What normally would take weeks or months of laboratory time can now be done within a few hours," said Peterson. Data collected from each scan are transferred directly to computers in his lab for analysis. Once cores are loaded in the Core Scanner, the instrument can be operated from remote locations over the Internet.
Peterson and his German collaborator, Gerald Haug, were featured in the July/August 2005 issue of American Scientist for their work studying core samples taken from the Cariaco Basin off the Venezuelan coast. Using a similar XRF machine, the scientists were able to find geological records of severe droughts between 800 and 1000 AD – coincident with the collapse of Classic Mayan civilization.
"We have a collection of several thousand sediment cores from all the world's oceans stored here at the university," Peterson said. "For each sample we take or receive, we usually study half and archive the remaining portion. Those archives will comprise the greater part of our research right now. We have a number of ongoing research projects, focusing mostly on climate change in the tropics, for which this new instrument will be invaluable."
Contact: Ivy Kupec
ikupec@miami.edu
305-421-4704
University of Miami Rosenstiel School of Marine & Atmospheric Science
How space travel affects the hearts of Space Shuttle astronauts
Study evaluates loss of heart mass in astronauts
Andover, Mass. – Royal Philips Electronics (NYSE: PHG, AEX: PHI) announced today that the National Aeronautics and Space Administration (NASA) is using the Philips iE33 echocardiography system and QLAB Quantification software to evaluate the effects of space flight on the hearts of Space Shuttle astronauts and, in the near future, astronauts on the International Space Station and ground-based analogs. Of interest to NASA researchers is the loss of heart mass brought on by space flight.
Astronauts commonly are thought to lose heart mass during prolonged flight. Two-dimensional echocardiography measurements reveal a 5 percent decrease, which usually returns within three days of being back on Earth. Researchers are interested in learning the cause of these changes. Possible explanations include heart atrophy caused by weightlessness, dehydration from space travel or error caused by the geometric assumptions used in two-dimensional echo.
The new technology being used captures a full-volume image of the beating heart in less than a minute and allows physicians to examine the heart as if they were holding it in their hands. It also allows the researchers to make accurate measurements of heart mass, ejection fraction, blood flow, strain rate and cardiac wall motion pre- and post-flight.
“We have a very short window of time in which to do an echo exam on the astronauts,” said David S. Martin of Wyle Laboratories, Inc., ultrasound lead for the NASA Cardiovascular Laboratory at the Johnson Space Center in Houston, Texas. “Live 3D Echo allows us to quickly grab all the image data we need to do a full examination of the heart anatomy and function and send the astronauts on their way. Following the image acquisition, we use off-line analysis software to do several measurements that help us evaluate changes after space travel.”
The use of this heart imaging and measurement technology will be part of ongoing research at the NASA Cardiovascular Laboratory. It will also complement the imaging done by a modified Philips HDI 5000 ultrasound system that was installed in the International Space Station’s Human Research Facility in 2001.
“These new ultrasound technologies help us efficiently conduct sophisticated cardiac research of astronauts and the effects of microgravity,” said Martin.
For further information please contact:
Steve Kelly
Philips Medical Systems
Tel +1 425 487 7479
email steve.kelly@philips.com
About Royal Philips Electronics
Royal Philips Electronics of the Netherlands (NYSE: PHG, AEX: PHI) is one of the world's biggest electronics companies and Europe's largest, with sales of EUR 30.4 billion in 2005. With activities in the three interlocking domains of healthcare, lifestyle and technology and 158,000 employees in more than 60 countries, it has market leadership positions in medical diagnostic imaging and patient monitoring, color television sets, electric shavers, lighting and silicon system solutions.
Andover, Mass. – Royal Philips Electronics (NYSE: PHG, AEX: PHI) announced today that the National Aeronautics and Space Administration (NASA) is using the Philips iE33 echocardiography system and QLAB Quantification software to evaluate the effects of space flight on the hearts of Space Shuttle astronauts and, in the near future, astronauts on the International Space Station and ground-based analogs. Of interest to NASA researchers is the loss of heart mass brought on by space flight.
Astronauts commonly are thought to lose heart mass during prolonged flight. Two-dimensional echocardiography measurements reveal a 5 percent decrease, which usually returns within three days of being back on Earth. Researchers are interested in learning the cause of these changes. Possible explanations include heart atrophy caused by weightlessness, dehydration from space travel or error caused by the geometric assumptions used in two-dimensional echo.
The new technology being used captures a full-volume image of the beating heart in less than a minute and allows physicians to examine the heart as if they were holding it in their hands. It also allows the researchers to make accurate measurements of heart mass, ejection fraction, blood flow, strain rate and cardiac wall motion pre- and post-flight.
“We have a very short window of time in which to do an echo exam on the astronauts,” said David S. Martin of Wyle Laboratories, Inc., ultrasound lead for the NASA Cardiovascular Laboratory at the Johnson Space Center in Houston, Texas. “Live 3D Echo allows us to quickly grab all the image data we need to do a full examination of the heart anatomy and function and send the astronauts on their way. Following the image acquisition, we use off-line analysis software to do several measurements that help us evaluate changes after space travel.”
The use of this heart imaging and measurement technology will be part of ongoing research at the NASA Cardiovascular Laboratory. It will also complement the imaging done by a modified Philips HDI 5000 ultrasound system that was installed in the International Space Station’s Human Research Facility in 2001.
“These new ultrasound technologies help us efficiently conduct sophisticated cardiac research of astronauts and the effects of microgravity,” said Martin.
For further information please contact:
Steve Kelly
Philips Medical Systems
Tel +1 425 487 7479
email steve.kelly@philips.com
About Royal Philips Electronics
Royal Philips Electronics of the Netherlands (NYSE: PHG, AEX: PHI) is one of the world's biggest electronics companies and Europe's largest, with sales of EUR 30.4 billion in 2005. With activities in the three interlocking domains of healthcare, lifestyle and technology and 158,000 employees in more than 60 countries, it has market leadership positions in medical diagnostic imaging and patient monitoring, color television sets, electric shavers, lighting and silicon system solutions.
Wednesday, September 20, 2006
Arctic summer ice anomaly shocks scientists
The image is an Envisat ASAR mosaic of Arctic ice acquired on Aug. 24, 2005. (Courtesy: Polar View)
Satellite images acquired from 23 to 25 August 2006 have shown for the first time dramatic openings – over a geographic extent larger than the size of the British Isles – in the Arctic's perennial sea ice pack north of Svalbard, and extending into the Russian Arctic all the way to the North Pole.
Observing data from Envisat's Advanced Synthetic Aperture Radar (ASAR) instrument and the AMSR-E instrument aboard the EOS Aqua satellite, scientists were able to determine that around 5-10 percent of the Arctic's perennial sea ice, which had survived the summer melt season, has been fragmented by late summer storms. The area between Spitzbergen, the North Pole and Severnaya Zemlya is confirmed by AMSR-E to have had much lower ice concentrations than witnessed during earlier years.
Mark Drinkwater of ESA's Oceans/Ice Unit said: "This situation is unlike anything observed in previous record low ice seasons. It is highly imaginable that a ship could have passed from Spitzbergen or Northern Siberia through what is normally pack ice to reach the North Pole without difficulty.
"If this anomaly trend continues, the North-East Passage or 'Northern Sea Route' between Europe and Asia will be open over longer intervals of time, and it is conceivable we might see attempts at sailing around the world directly across the summer Arctic Ocean within the next 10-20 years."
During the last 25 years, satellites have been observing the Arctic and have witnessed reductions in the minimum ice extent – the lowest amount of ice recorded in the area annually – at the end of summer from around 8 million km² in the early 1980s to the historic minimum of less than 5.5 million km² in 2005, changes widely viewed as a consequence of greenhouse warming.
Satellite observations in the past couple of years have also shown that the extent of perennial ice is rapidly declining, but this strange condition in late August marks the first time the perennial ice pack appears to exhibit thinner and more mobile conditions in the European sector of the Central Arctic than in earlier years.
Both sets of images were taken by two different satellite instruments – ASAR on the left and AMSR-E on the right. In the coloured AMSR-E images, ice cover, or the concentration of ice, is represented by the colour. Pink represents pack ice and the colour blue open water. Intermediate colours orange, yellow, and green indicate lower ice concentrations of 70%, 50% and 30%, respectively. In the ASAR images, ice cover is represented by the uniform grey area which extends radially-outwards from the North Pole, represented by the central black hole.
The set of images on the top were both acquired on 24 August 2005, while the bottom left ASAR image was acquired on 23 August 2006 and the AMSR-E on 24 August 2006. In 2005, the uniform grey area in the ASAR image and the pink colour in the AMSR-E image are both consistent all the way around the pole (black hole), indicating pack ice with 100% ice concentration.
However in 2006 there is a significant extent of leads – fractures and openings in the sea-ice cover – just below the pole in both the ASAR image, seen as splashes of dark grey and black, and the AMSR-E image (with British Isles shown for scale), seen by the high concentration of yellow, orange and green colours, signifying low ice concentrations.
In the last weeks, what was open water has begun to freeze, as the autumn air temperatures over the Arctic begin to fall. Although a considerable fraction of darker leads can still be seen in the area using ASAR, the AMSR-E sensor no longer shows openings.
ASAR is an active microwave instrument which sends periodic radar pulses toward the Earth and measures the signals return. AMSR-E is a passive microwave instrument which does not send radar pulses down but receives radiation naturally emitted from the Earth. Passive microwave data contain a certain amount of ambiguity in interpretation of ice types, particularly in mid summer during melting. However, this ambiguity is removed in high resolution active microwave data.
Though the reason for the considerable change in the ice pack configuration is still unknown, it is likely due to the stormy weather conditions in August that characterised the month.
The effect stormy conditions have on ice is illustrated in this ASAR image, taken on 25 August 2006, as the ice in the red circle is divergent as a consequence of a low pressure system centred on the North Pole.
"As autumn freeze-up begins, the current pattern will undoubtedly precondition the ice situation in the Central Arctic for the subsequent ice season," Drinkwater said.
Contact: Mariangela D'Acunto
mariangela.dacunto@esa.int
39-069-418-0856
European Space Agency
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