Increased amounts of air pollution in China over last 50 years reduces days of rain by up to a quarter

New research shows that air pollution in eastern China has reduced the amount of light rainfall over the past 50 years and decreased by 23 percent the number of days of light rain in the eastern half of the country. The results suggest that bad air quality might be affecting the country's ability to raise crops as well as contributing to health and environmental problems.

The study links for the first time high levels of pollutants in the air with conditions that prevent the light kind of rainfall critical for agriculture. Led by atmospheric scientist Yun Qian at the Department of Energy's Pacific Northwest National Laboratory, the study appears August 15 in the Journal of Geophysical Research-Atmospheres.

"People have long wondered if there was a connection, but this is the first time we've observed it from long-term data," said Qian. "Besides the health effects, acid rain and other problems that pollution creates, this work suggests that reducing air pollution might help ease the drought in north China."

Drier Times

China's dramatic economic growth and pollution problems provide researchers an opportunity to study the connection between air quality and climate. Rain in eastern China — where most of the country's people and pollution exist — is not like it used to be.

Over the last 50 years, the southern part of eastern China has seen increased amounts of total rainfall per year. The northern half has seen less rain and more droughts. But light rainfall that sustains crops has decreased everywhere. A group of climate researchers from the U.S., China and Sweden wanted to know why light rain patterns haven't followed the same precipitation patterns as total rainfall.

Previous work has shown that pollution can interfere with light rain above oceans, so the team suspected pollution might have something to do with the changes over land. Light rain ranges from drizzles to 10 millimeters of accumulation per day and sustains agriculture. (Compared to heavy rain that causes floods, loss of light rain has serious consequences for crops.)

While the light rains have diminished, pollution has increased dramatically in China in the last half of the 20th century. For example, while China's population rose two and a half times in size, the emissions of sulfur from fossil fuel burning outpaced that considerably — rising nine times.

Sky Gremlins

Air pollution contains tiny, unseen particles of gas, water and bits of matter called aerosols. Aerosols — both natural and human-caused (anthropogenic) — do contribute to rainfall patterns, but the researchers needed to determine if pollution was to blame for China's loss of rain and how.

To find out, the team charted trends in rainfall from 1956 to 2005 in eastern China, which has 162 weather stations with complete data collected over the entire 50 years.

From this data, the team determined that both the north and south regions of eastern China had fewer days of light rain — those getting 10 millimeters per day or less — at the end of the 50 year timespan. The south lost more days — 8.1 days per decade — than the north did, at 6.9 days per decade. However, the drought-rattled north lost a greater percentage of its rainy days, about 25 percent compared to the south's 21 percent.

"No matter how we define light rain, we can see a very significant decrease of light rain over almost every station," said Qian.

Up Up & In the Way

To probe what caused the loss of rainfall, the team looked at how much water the atmosphere contained and where the water vapor traveled. Most parts of eastern China saw no significant change in the amount of water held by the atmosphere, even though light rains decreased. In addition, where the atmosphere transported water vapor didn't coincide with light rain frequency.

These results suggested that changes in large-scale movement of water could not account for the loss of the precipitation. Some of pollution's aerosols can seed clouds or form raindrops, depending on their size, composition and the conditions in which they find themselves. Because these skills likely contribute to rainfall patterns, the researchers explored the aerosols in more depth.

Cloud droplets form around aerosols, so the team determined the concentration of cloud droplets over China. They found higher concentrations of droplets when more aerosols were present. But more droplets mean that each cloud droplet is smaller, in the same way that filling 10 ice cream cones from a quart of ice cream results in smaller scoops than if the same amount were put in only five cones.

This result suggested that aerosols create smaller water droplets, which in turn have a harder time forming rainclouds. The team verified this with supercomputer models of pristine, moderately polluted or heavily polluted skies. In the most heavily polluted simulation, rain fell at significantly lower frequencies than in the pristine conditions.

An examination of the cloud and rain drops showed that these water drops in polluted cases are up to 50 percent smaller than in clean skies. The smaller size impedes the formation of rain clouds and the falling of rain.

Qian said the next step in their research is to examine new data from the DOE's Atmospheric Radiation Measurement Climate Research Facility in the central eastern Chinese city of Shouxian. The data was collected from April to December of 2008.

"This work is important because modeling studies of individual cases of pollution's effect on convective clouds have shown varying results, depending on the environmental conditions," said coauthor Ruby Leung. "The ARM data collected at Shouxian should provide more detailed measurements of both aerosols and clouds to enable us to quantify the impacts of aerosols on precipitation under different atmospheric and pollution conditions."

The work was supported by the Office of Biological and Environmental Research within the DOE Office of Science under a bilateral agreement on regional climate research with the China Ministry of Science and Technology.

Energy Efficient Tape Solution Simplifies Backup with Easy Management, Integrated Security and Intelligent Self-Monitoring
 
Spectra Logic announced the U.S. Army’s Tank-Automotive Research, Development and Engineering Center (TARDEC) agency in Michigan awarded Spectra Logic with a federal contract for two Spectra T950 tape libraries using LTO-4 technology.
 
The U.S. Army TARDEC removed a Sun StorageTek L700e tape library and replaced it with the T950, and realized immediate savings in backup operator time and cost, freed several square feet of data center floor space, increased capacity by 990 percent and eased administration through the library’s user-friendly management interface.  With two Spectra T950 libraries, the U.S. Army TARDEC was able to designate one for classified data and the other for unclassified data, which eased its administrative burden. The Spectra T950 tape libraries work with Symantec NetBackup software to back up and protect more than 22TB of data weekly.
 
“Spectra Logic continues to expand its presence throughout the Department of Defense with this recent success at the Army TARDEC,” said Brian Grainger, vice president of sales. “The Spectra T950 leads the market with the highest storage density available today along with significant energy and space savings, and ease of use, all contributing significantly to the U.S. Army contract award.”

Over the last six years Enabling Grids for E-sciencE (EGEE) has grown to become the world's largest multi-disciplinary grid infrastructure, with tens of thousands of users. In Barcelona this month the flagship EC-funded project meets for its final annual conference. Next year will see the inauguration of EGEE's successor, the European Grid Initiative (EGI), and this pivotal gathering of the grid community will allow for reflection on the successes of the project, as well as marking a major step forward on the path towards a nationally-focused sustainable grid infrastructure, to benefit all European researchers for years to come. The transition from EGEE to EGI represents a welcome move from short-term project funding to sustained support on a national and international level, which will enable users to continue using grid infrastructures – now and in the future.

Successes have been numerous and EGEE already caters for a multitude of disciplines. This final annual conference is an opportunity for the user communities to showcase their work and achievements, and demonstrate the power of grid technology. There will be live demonstrations from diverse scientific research fields, including many from medical research - notably neuGrid, studying degenerative diseases such as Alzheimer's, RadioTherapy Grid optimising the use of radiotherapy in cancer treatment and EUAsiaGrid helping research into monitoring future flu pandemics.

While the medical community has benefited greatly it is not the only one to increasingly rely on grids. The computing power and data storage offered by EGEE has allowed scientists to think big - from modelling weather using the grid with WRF4G, predicting the distribution of marine life with AquaMaps, to EUAsiaGrid’s software helping authorities to cope in the aftermath of an earthquake. The breadth and quality of scientific research supported by EGEE is a testament to the versatility of computing grids.

It is this versatility that has attracted industry. EGEE has worked with the business community since the early days of grids. Each year, the dedicated business track increases the collaboration between EGEE and industry.  This year is no different, demonstrating the evolution of grid computing by highlighting not only key areas such as cloud computing and service level agreements, but also unveiling prime examples of technology transfer from science and academia to commercialisation.

With cloud computing generating increasing excitement in the business community, EGEE is working to integrate the two services. Two sessions at EGEE’09 will present a range of projects working on grids and clouds, such as StratusLab which is bringing grids and clouds together to create benefits for both science and industry.

As in previous years, the conference has attracted major grid computing figures from around the world as keynote speakers, including locally-based speaker Gonzalo Merino from PIC, who is in charge of Spain’s Tier-1 data centre for the Large Hadron Collider, Jennifer Schopf, from the National Science Foundation’s Office of CyberInfrastructure in the US and Kostas Glinos, who leads the Géant & e-Infrastructures Unit of the Directorate General for Information Society and Media at the European Commission. EGEE’09 will also be a key milestone in the preparations of pan-European projects defined within the European Strategy Forum on Research Infrastructures (ESFRI), presented at the conference by Professor John Wood, chair of the European Research Area Board and former Chair of ESFRI.

Today the LHC circulated two beams simultaneously for the first time, allowing the operators to test the synchronization of the beams and giving the experiments their first chance to look for proton-proton collisions. With just one bunch of particles circulating in each direction, the beams can be made to cross in up to two places in the ring. From early in the afternoon, the beams were made to cross at points 1 and 5, home to the ATLAS and CMS detectors, both of which were on the look out for collisions. Later, beams crossed at points 2 and 8, ALICE and LHCb. Screens showing two beams in the LHC

“It’s a great achievement to have come this far in so short a time,” said CERN Director General Rolf Heuer. “But we need to keep a sense of perspective – there’s still much to do before we can start the LHC physics programme.”

Beams were first tuned to produce collisions in the ATLAS detector, which recorded its first candidate for collisions at 14:22 this afternoon. Later, the beams were optimised for CMS. In the evening, ALICE had the first optimization, followed by LHCb.

“This is great news, the start of a fantastic era of physics and hopefully discoveries after 20 years' work by the international community to build a machine and detectors of unprecedented complexity and performance," said ATLAS spokesperson, Fabiola Gianotti.

“The events so far mark the start of the second half of this incredible voyage of discovery of the secrets of nature,” said CMS spokesperson Tejinder Virdee.

“It was standing room only in the ALICE control room and cheers erupted with the first collisions” said ALICE spokesperson Jurgen Schukraft. “This is simply tremendous.”

“The tracks we’re seeing are beautiful,” said LHCb spokesperson Andrei Golutvin, “we’re all ready for serious data taking in a few days time.”

These developments come just three days after the LHC restart, demonstrating the excellent performance of the beam control system. Since the start-up, the operators have been circulating beams around the ring alternately in one direction and then the other at the injection energy of 450 GeV. The beam lifetime has gradually been increased to 10 hours, and today beams have been circulating simultaneously in both directions, still at the injection energy.

Next on the schedule is an intense commissioning phase aimed at increasing the beam intensity and accelerating the beams. All being well, by Christmas, the LHC should reach 1.2 TeV per beam, and have provided good quantities of collision data for the experiments’ calibrations.

ALICE Event

ATLAS Event

CMS Event

LHCb Event

 

Daniel Pedro knew when he was a sophomore at Santa Fe Indian School that he wanted to be an anthropologist. He also knew that as a Zuni, he would not be able to touch human remains – a common task for physical anthropologists.

“It was kind of a barrier,” said Pedro, a 20-year-old freshman at the University of New Mexico-Gallup. “I had to find a way to work around it.”

Pedro began to look for that way through his participation in the New Mexico Supercomputing Challenge. The Challenge aims to teach teams of middle and high schools students how to use powerful computers to analyze, model and solve real world problems and awards prizes in various categories.

Pedro hit on the idea of studying the faces of living puebloans in search of consistent similarities and then projecting that data onto the past as a way to identify and repatriate skeletal remains. As stated in the executive summary of his project, “My goal … is to make it easier for anthropologists to figure out which tribe/pueblo the remains belong to on the computer, instead of disrespecting Native customs and damaging the skull.”

An early advisor, UNM Curator of Human Osteology Heather Edgar, told Pedro that the people of the pueblos, both present and past, were too mixed to make the sort of determinations he was seeking. Nevertheless, she was impressed by his inventive approach to problem solving, and encouraged him by giving advice on how to go about his project. She also gave him a medical diagram of a human skull with which to start his studies.

“We need a Native perspective in anthropology, and especially a perspective that comes from working with living communities,” Edgar said.

Pedro’s unique project soon attracted several other advisors and mentors.

“They were impressed by the fact it was a student who wanted to do this kind of work, and a high school student and a Native American at that,” Pedro said.

Pedro began to work in a computer program called StarLogo, which allowed him to rotate two objects side by side and compare the objects in different profiles.  He had decided to concentrate on the human skull, comparing shapes that represented skulls. His goal was to create a method for anthropologists to determine which tribe or pueblo a skull might belong to with only minimal handling. The result was an entry for the Supercomputing Challenge called “Scan of the Past.”

“He learned a lot about the mathematics of 3D computer graphics and the rotation and scaling of 3D objects on the computer,” said Irene Lee, who oversees a grant program at Santa Fe Institute, and was previously lead facilitator for the SFI-MIT Adventures in Modeling program in Santa Fe when she worked with Pedro.

For this phase of his project, he received the Judges’ Choice Award for “Integrating Computation into Anthropology” from the Supercomputing Challenge.

The second phase of his work was on a new version of the “Scan of the Past,” with the help of Steve Guerin of Redfish Group, a Santa Fe-based business that specializes in data mining and visualizing. Guerin helped Pedro during his senior year construct a proxy data set, which would allow him to practice clustering techniques and classification algorithms, or in other words, construct real world data. Pedro learned how to integrate actual facial data collected after he photographed and studied 15 landmarks on the faces of 45 individuals – fellow students whom he persuaded to participate in his project. Generally, says Edgar, studies are made with as many as 50 landmarks on a human skull, but because Pedro was concentrated on faces, his study was limited to far fewer.

Although this phase of the project did not earn an award, he did receive an award from the Supercomputing Challenge in 2008-2009 for creating a graphic poster and creating a logo.

“Daniel took on a computational challenge that was meaningful to him and his community,” Lee said. “He is a great role model of a self-directed student researcher. He found an interesting, unsolved problem he could address. He overcame many obstacles and persevered with the project over several years.”

“It was great to have help from so many mentors,” Pedro said. “I had wondered if my project would be taken seriously because this was something really new.”

After graduating from high school in 2008, Daniel went on to enroll in UNM-Gallup, where he is studying, among other subjects, anthropology with Teresa Wilkins, professor of anthropology. Last year, he got a taste of the museum work he hopes to make a career by working at A:shiwi A:wan Museum and Heritage Center in Zuni, where he learned how to care for exhibits and worked with the photo collection. He also got some good career experience this past summer by participating in the Conference on Archaeoastronomy of the American Southwest, Camp Verde, Ariz., where, with researcher Anna Sofaer, writer, artist and founder of the Solstice Project, he presented a poster on a new interactive computer model of the Chaco Canyon Sun Dagger site.

His work with Sofaer helped him see that Native Americans “did marvelous things,” and reinforced his idea that, when studying historic sites, “It’s best to listen to Native American oral traditions about what happened at these sites. If we can integrate these traditions with what we can learn from modern technology, we can create another level of thinking.”

As Pedro continues his journey toward a bachelor’s degree in Southwest Studies at UNMG, and beyond, to a Ph.D., the intention that inspired his high school project will be very much with him. He wants to continue to explore ways to use technology to repatriate human remains and relics to the tribes they belong to. At the same time, he wants to build on what he learned from his high school project and his work with the Solstice Project to bring computers into anthropological work in a way that will help Native Americans understand who they are.

“As an example, time may overtake the original Sun Dagger site and it will become part of nature, but a replica of the model will be there to teach how Native Americans used the solstice at Chaco, and how they measured time,” Pedro said.

Wilkins applauds Native students like Pedro who are looking to apply “sophisticated technology to [solve] real problems,” and echoes his hope that today’s Natives will become empowered to make their own identifications of remains in order to repatriate them. She also believes that such an applied approach to anthropology as Daniel Pedro’s project undertook may be “highly significant in empowering Native people to conduct their own research.”

Pedro also hopes his vocation as anthropologist will help show Native Americans that eventually, they should not have to take classes to “be native.” After all, he points out, most of the non-natives who have taught American Indians about their history and culture cannot have complete information because, “There is a limit as to how much we can share. Keeping the culture or religion with the community keeps our identity within the community, rather than having it spill out.” Ideally, he says, those studying and interpreting the research some day will be Natives who will not only share this knowledge with their communities, but also mediate what is shared with non-Natives.

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