CHEMICAL TRACERS

By Pam Eastlick

Welcome to The Deep science and technology column where we cover topics from the deep sea to deep space and beyond.

So, that bag of spinach you just took out of the fridge has been in there for a while. Is it still safe to eat? Would you like a spinach bag that changed color when harmful levels of bacteria were present? How about a device that could be implanted in your body that would monitor the sugar levels in your blood without those twice-daily finger pricks? It may sound like science fiction but researchers at Tufts University are designing such devices out of . . . silk.

Current optical devices are based primarily on glass, semiconductors and plastics. But the harsh solvents and extreme temperatures needed to make them make it impossible to incorporate bioactive sensing components into the devices. Chemical residues and lack of biodegradability also limit environmental and medical applications. Furthermore, biological components typically need to be stored at controlled temperatures to retain their activity.

Silk proteins are a natural for integrating optical and biological functions. They can be processed in water at ordinary temperatures and patterned to generate a wide range of optical elements, including ultrathin films, thick films, and tiny and large-diameter fibers. Silk proteins also offer excellent surface quality and transparency, which are necessary for high-quality optics. And equally important, they’re mechanically robust.

To make their devices, Tufts scientists boiled silkworm cocoons in water to extract the glue-like sericin proteins. The purified silk protein solution was poured onto holographic diffraction gratings with spacing as fine as 3600 grooves/mm. The cast silk solution was air dried to create solid silk films that were cured in water, dried and optically evaluated. A similar process was used to create lenses, microlens arrays and holograms.

Since the films are made at room temperature, any included biological receptors stay active after the solution has hardened into the film. The Tufts team embedded three very different biological agents in their silk solution: a protein (hemoglobin), an enzyme (horseradish peroxidase) and an organic pH indicator (phenol red). All three agents maintained their activity for long periods when the silk film was simply stored on a shelf. According to the Tufts researchers, this is truly amazing when you consider that the enzyme becomes inactive if left unrefrigerated for a few days. The researchers also discovered they could alter how light travels through the silk film with certain chemicals to create an optical signal for different kinds of biological activity.

Silk optics has captured the interest of the Defense Department, which has funded and been instrumental in enabling rapid progress of the research. If the military is interested, you can be sure that more advances are coming in this area. Silk rules!!

And in case you were planning on going on a crime spree in the mainland and then coming back here to the Marianas to hide, you might want to reconsider. Recent research has shown that the beverages you drink can be used to track your location through time.

The body removes hydrogen and oxygen atoms from the water and beverages you drink and uses them to make proteins, including the protein in hair. The proportions of the isotopes in hydrogen and oxygen vary geographically with higher values in low-latitude, low-elevation, or coastal regions, for instance, and lower values elsewhere.

The finding may help trace the origin of drinks or help criminal investigators identify the geographic travels of crime suspects and other individuals through analysis of hair strands.

IN YOUR HANDS

By Pam Eastlick

Welcome to The Deep science and technology column where we cover topics from the deep sea to deep space and beyond.

One of the wonders of nature is what’s at the end of your arm. The human hand is an amazing machine that’s capable of all sorts of astounding feats. It can pick up, clench and caress. Although you certainly take your hands for granted, just imagine what life would be without them.

Robots need hands too, and building them has been a real challenge. Now, researchers at Cornell University and iRobot (the makers of the absolutely awesome Roomba vacuum cleaner) have gotten together and made a robotic hand. Ah, you’re thinking, what’s at the end of my arm but made of metal, right? Well, not exactly. They made it out of coffee and a party balloon. Say whut??

They call it a universal gripper and not a hand, since it conforms to the object it’s grabbing rather than being designed for particular objects, said Hod Lipson, Cornell associate professor of mechanical engineering and computer science. He worked with Chris Jones at iRobot Corp.

"This is one of the closest things we’ve ever done that could be on the market tomorrow," Lipson said. The gripper could be used to dismantle explosive devises or to move potentially dangerous objects. It could also be used on robotic arms in factories and perhaps most importantly, on prosthetic limbs.

Here’s how it works: An everyday party balloon is filled with ground coffee and attached to a robotic arm. The coffee-filled balloon presses down and deforms around the desired object, and then a vacuum sucks the air out of the balloon, solidifying its grip. When the vacuum is released, the balloon becomes soft again, and the gripper lets go.

Coffee is a particulate material which means it’s made of a lot of individually solid particles. Particulate materials have what’s called a jamming transition. When the particles aren’t packed tightly together, they move around each other like a liquid, but when they’re tightly packed they become solid and can no longer slide past each other. You’ve seen this yourself if you drink vacuum-packed coffee which is hard as a brick until the package is unsealed.

"The ground coffee grains are like lots of small gears," Lipson said. "When they aren’t pressed together they can roll over each other and flow. When they are pressed together just a little bit, the teeth interlock, and they become solid. What’s particularly neat with the gripper is that here we have a case where a new concept in basic science provided a fresh perspective in a very different area — robotics — and then opened the door to applications none of us had originally thought about.”

As for the right particulate material, anything that can jam will do in principle, and early prototypes involved rice, couscous and even ground- up tires. They settled on coffee because it’s light but also jams well. Sand did better on jamming but was prohibitively heavy. What sets the jamming-based gripper apart is its good performance with almost any object, including a raw egg or a coin — both notoriously difficult for traditional robotic grippers.

Basic principles, new science. Let’s all give these researchers a big hand!

Graduate student John Amend, left, and associate professor Hod Lipson with the universal robotic gripper. (Credit: Robert Barker/University Photography)

OLD SCHOOL TECHNOLOGY

By Pam Eastlick

I thought we’d delve into the technology file today. Of course, in today’s world, ‘technology’ has almost become synonymous with ‘computer technology’, but there’s plenty of the other kind around and new stuff is being discovered all the time.

We have our share of earthquakes here on Guam, but they typically don’t cause the destruction found in other places because we also have typhoons here and we build with concrete.

But concrete is a lot more vulnerable to earthquakes than it is to typhoons and some of you may remember that I featured an item several years ago about ‘self-healing concrete’; concrete that basically fixes its own cracks. I thought it was a wonderful idea, but in the ensuing years, no ‘self-healing concrete’ has made its appearance. But that could be subject to change.

HEAL IT UP

Apparently, the problem with the old ‘smart materials’ (another buzz word for the genre) is that they were difficult to commercialize. After all, somebody has to make money from any new technological invention in order for it to spread rapidly. But a new self-healing concrete has been developed and tested by a graduate student at the University of Rhode Island that may be cost-effective.

Michelle Pelletier, a URI master’s degree candidate, embedded a microencapsulated sodium silicate healing agent directly into a concrete matrix. When tiny stress cracks begin to form in the concrete, the capsules rupture and release the healing agent into the adjacent areas.

The sodium silicate reacts with the calcium hydroxide naturally present in the concrete to form a calcium-silica-hydrate product that heals the cracks and blocks the pores in the concrete. The chemical reaction creates a gel-like material that hardens in about a week.

They conducted stress tests by comparing a standard concrete mix with one containing just two percent of Ms. Pelletier’s ‘healing’ agent. The mix containing the sodium silicate recovered 26 percent of its original strength compared to just 10 percent recovery by the standard mix. The testers believe that increasing the quantity of the sodium silicate would probably improve the recovered strength of the concrete.

The self-healing concrete concept (try saying THAT three times fast!) has the potential to be a lucrative one. In previous attempts, researchers have laced concrete with bacteria spores that secrete calcium carbonate to fill the cracks and pores, while others have embedded glass capillaries with a healing agent, but the process of filling the capillaries with the agent is long and tedious.

And the next step for Ms. Pelletier is one that could have REAL importance for us here in the damp tropics. She intends to conduct a study to see if her sodium silicate healing agent also acts as a corrosion inhibitor. Here in the Marianas, we know from rusty rebar.

Ms. Pelletier thinks that her sodium silicate could act as a rust preventative by two mechanisms. First, the sodium silicate fills in the pores thus helping prevent water from reaching the rebar through the concrete itself and also deposits a film on the outside of the concrete which could help reduce the rebar corrosion rate.

One additional advantage to the use of self-healing concrete is that it could reduce the significant CO₂ emissions that result from concrete production. Concrete production is very energy intensive. When all aspects of the industry are included like mining, transportation and concrete plants are considered, the industry is responsible for about 10 percent of all CO₂ emissions in the United States.

If Ms Pelletier’s self-healing concrete can lengthen the life of the concrete and reduce maintenance and repairs, it will ultimately reduce the production of excess amounts of concrete and result in a decrease in CO₂ emissions. And that is a concrete idea!!

STICK IT UP

Although those carefully controlled tests and experiments do produce good science, there is a nagging feeling that most real scientific progress happens, not in those carefully controlled experiments but when someone says “Hmmm, that’s funny. I wonder what caused THAT to happen”

Now, an accidental discovery in a wood products lab at Oregon State University has produced a new pressure-sensitive adhesive that may revolutionize the tape industry. It’s an environmentally benign product that works very well and costs much less than existing adhesives based on petrochemicals.

The new adhesive can be produced from a range of vegetable oils, and may find applications for duct tape, packaging tape, stick-on notes, labels, even postage stamps, in fact almost any type of product requiring a pressure-sensitive adhesive.

The discovery was made by accident while OSU scientists were looking for an adhesive that would be solid at room temperature and melt at elevated temperatures. The vegetable oil-based adhesive they were testing was a spectacular failure

Then one of the students noticed that at a certain stage in the process, the compound they were testing became a very sticky resin. They stopped, put some on a piece of paper and it stuck to everything. It was a very strong adhesive, and it peeled right off. The bell went ding and the two researchers then worked to develop a pressure-sensitive adhesive, the type used on many forms of tape, labels, and notepads.

It’s an amazing compound. It’s incredibly simple to make, doesn’t use any organic solvents or toxic chemicals, and is based on vegetable oils, not petrochemicals. You can make it at about half the cost of existing technologies and it appears to work just as well."

There have been previous attempts to make pressure-sensitive adhesives from vegetable oils, but they used the same type of polymerization chemistry as the acrylate-based petrochemicals now used to make tape. There wasn’t much cost reduction and they didn’t work very well.

The new method uses a different type of polymerization and produces pressure-sensitive adhesives adaptable for a wide range of uses, that work well, cost much less, and are made from renewable crops such as soy beans, corn or canola oil, instead of petroleum-based polymers. OSU has applied for a patent on the technology, and they’re looking for a commercial partner.

So . . . green concrete and green sticky. Of course, we’ve been building for a very long time and although the Romans invented concrete, we’ve always had a need to stick stuff together. A while back, I became curious about the pyramids in Egypt. If the Romans invented concrete and mortar, what holds them together? Luckily, I know an Egyptologist and I asked her. She said that the Egyptians did have mortar, but that mainly what holds the pyramids together is good old-fashioned gravity.

The ancient Chinese had mortar too, but it may not be the kind you’re thinking of. Read on!

BEAT IT, EAT IT, STICK IT ON THE WALL

So . . . you have these stone blocks and you want to build a house. Your house isn’t pyramid-shaped and when you stack them up, they fall over. So . . . what do you use to make them stick together? If you lived in ancient China, the answer apparently was: dinner.

Scientists have recently discovered the secret behind an ancient Chinese super-strong mortar. It’s made from sticky rice, the delicious "sweet rice" that’s a mainstay in virtually all Asian dishes. They’ve also concluded that the mortar remains the best available material for restoring ancient buildings.

The researchers noted that construction workers in ancient China developed sticky rice mortar about 1,500 years ago by mixing sticky rice soup with slaked lime. Slaked lime is limestone that’s been calcined; heated to a high temperature, and then exposed to water. Sticky rice mortar probably was the world’s first composite mortar, made with both organic and inorganic materials.

The mortar was stronger and more resistant to water than pure lime mortar; it was one of the greatest technological innovations of its time. Builders used it to construct buildings like tombs, pagodas, and city walls, some of which still exist today. Some of these structures have survived modern bulldozers and powerful earthquakes.

The research identified amylopectin, a type of polysaccharide, or complex carbohydrate, found in rice and other starchy foods, as the "secret ingredient" responsible for the mortar’s legendary strength.

The study shows that the ancient mortar is an organic-inorganic composite material. The inorganic component is calcium carbonate, and the organic component is amylopectin, which comes from the sticky rice soup added to the mortar. The amylopectin in the mortar acted as an inhibitor. The growth of the calcium carbonate crystal was controlled, and a compact microstructure was produced, that is the basis for the mortar’s incredible performance.

To determine if sticky rice can aid in building repair, the scientists prepared lime mortars with varying amounts of sticky rice and tested their performance compared to traditional lime mortar. The test results showed that sticky rice-lime mortar has more stable physical properties, has greater mechanical strength, and is more compatible with the existing mortar, making it a suitable restoration mortar for ancient masonry.

SEEING THE WORLD

By Pam Eastlick

Welcome to The Deep science and technology column where we cover topics from the deep sea to deep space and beyond.

Well, we’ve done plants and animals and global warming and medicine lately, and now I think it’s time to dip into the technology file to see what weird and wonderful things the technogeeks are up to. So off we go to the Alice in Wonderland world of technology.

Don’t you just love the new cameras and photophones? And the ease of putting all those infinite pictures onto the net for all your friends and families and grandparents and prospective employers and everyone else to see is just wonderful. Unless of course, things get posted that you didn’t want everyone to see. But we won’t get into that here.

Let’s stick to talking about vacation photos and perhaps posting them on Flickr. It turns out lots of folks have done that, and well, read on!

BUILDING ROME IN A DAY

We all know that Rome wasn’t built in a day. It took 10 years to build the Coliseum and almost 100 years to build St. Peter’s Basilica. But researchers at the University of Washington have developed a new computer algorithm that used hundreds of thousands of tourist photos to automatically reconstruct the city of Rome. It took about a day.

The tool is the most recent in a series developed at UW to harness the enormous digital photo collections available on photo-sharing Web sites. The digital Rome was assembled from 150,000 tourist photos tagged with the word "Rome" or "Roma" that were downloaded from the popular photo-sharing Web site, Flickr.

Computers analyzed each image and in 21 hours combined them to create a 3-D digital model. Using this model, a viewer can fly around Rome’s landmarks, from the Trevi Fountain to the Pantheon to the inside of the Sistine Chapel. Earlier versions of the UW photo-stitching technology are known as Photo Tourism. That technology was licensed in 2006 to Microsoft, which now offers it as a free tool called Photosynth.

In addition to Rome, the team recreated the Croatian coastal city of Dubrovnik, processing 60,000 images in less than 23 hours using a cluster of 350 computers, and Venice, Italy, processing 250,000 images in 65 hours using a cluster of 500 computers. Many historians see Venice as a candidate for digital preservation before water does more damage to the city, the researchers said.

Transitioning from landmarks to cities — going from hundreds of photos to hundreds of thousands of photos — is not trivial. Previous versions of the Photo Tourism software matched each photo to every other photo in the set. But as the number of photos increases the number of matches increases exponentially. A set of 250,000 images would take at least a year for 500 computers to process and a million photos would take more than a decade using the previous version.

The newly developed code works more than a hundred times faster than the previous version. It first establishes likely matches and then concentrates on those parts. The code also uses parallel processing techniques, allowing it to run simultaneously on many computers, or even on remote servers connected through the Internet. This new, faster code makes it possible to tackle more ambitious projects.

This technique could create online maps that offer viewers a virtual-reality experience. The software could build cities for video games automatically, instead of doing so by hand. It also might be used in architecture for digital preservation of cities, or integrated with online maps. In the near term, the "Rome in a Day" code could be used with Photo Tourism, Photosynth or other software designed to view the model output.

The research was supported by the National Science Foundation, the Office of Naval Research and its Spawar lab, Microsoft Research, and Google.

The Colosseum as seen in the digital reconstruction. Each triangle is where a person was standing when he or she took a photo (Credit: University of Washington)

So, we’re actually looking at the first step in creating a virtual world without the flies and the heat and the smells. I’m not so sure that’s a really good tradeoff, but then I’ve always had just a whiff of the Luddite about me!

And now we’ll move on to a new controversial technology that’s being put to some uses that aren’t quite so controversial.

SEE THROUGH

We’ve all heard about terahertz radiation or THz. That’s the technology they want to put in airports to cut down on the risk of people smuggling weapons onboard an airplane concealed in their clothing. Terahertz radiation sees right through your clothes and that’s why a lot of people are not happy about being seen au natural at the airport!

It turns out that terhertz radiation has other uses because it can not only see through clothes, it can see through paint. German researchers are using THz to look at old paintings and murals.

Conventional wisdom says that once you paint over a mural, it’s gone because current methods can’t reveal the picture beneath without damaging it. Many church paintings are hidden from sight because they were painted over centuries ago. As tastes and religious fervors changed, walls were painted and repainted many times. In many old churches and other buildings, layers of paintings from various epochs can now be found superimposed on top of each other.

If you strip the paint to the original picture using conventional methods you risk damaging it. You also destroy the layers of pictures above it and they may be worthy of preservation too. So what’s a poor conservationist to do? Use terahertz radiation!

THz radiation can penetrate plaster and lime washes even if the layer is relatively thick. And unlike other radiation wavelengths like ultraviolet, THz radiation doesn’t damage the art. Infrared beams don’t work because they can’t penetrate deep enough and microwaves can’t provide the necessary width and depth resolution.

The German researchers developed a mobile system that can be used anywhere to conduct the examinations. The scanner travels over the wall without touching it and has two measuring heads; one transmits the radiation, the other picks up the reflected beams.

Each layer and each pigment reflects the transmitted pulses differently so that picture contrast as well as depth information can be obtained. The measured results provide information about the thickness of the painted layers, what pigments were used and how the colors are arranged. A specially developed software system puts the measured results together to form a picture displaying the structure of the concealed paintings.

The scientists have already succeeded in revealing the structures of concealed pictures on a test wall where several different pictures were painted and then painted over with other pictures. The next step will be to conduct a practical test in a church.

The mobile scanner at work on a test wall. A software system reveals the structure of the concealed paintings. (Credit: Copyright Fraunhofer IWS)

And now we come to a story that still just blows me away. One of the things I definitely remember from high school science classes were the great strides that had been made in microscopy. It was the beginning of the era of the electron microscope and astounding discoveries were being made everywhere. But there was one boundary that everybody agreed on. No matter how good microscopes got, we would NEVER be able to see individual atoms!

Just goes to show you that ‘never’ is a very tricky word that should probably be avoided in most cases!

SEEING FARTHER

Using the latest in aberration-corrected electron microscopy, researchers at the Department of Energy’s Oak Ridge National Laboratory and their colleagues have obtained the first images that distinguish individual light atoms such as boron, carbon, nitrogen and oxygen. (Yes, boys and girls, they have taken pictures of individual ATOMS).

The ORNL images were obtained with a Z-contrast scanning transmission electron microscope (STEM). Individual atoms of carbon, boron, nitrogen and oxygen–all of which have low atomic numbers–were resolved on a single-layer boron nitride sample.

"This research marks the first instance in which every atom in a significant part of a non-periodic material has been imaged and chemically identified," said Materials Science and Technology Division researcher Stephen Pennycook. "It represents another accomplishment of the combined technologies of Z-contract STEM and aberration correction."

The new high-resolution imaging technique enables materials researchers to analyze, atom by atom, the molecular structure of experimental materials and discern structural defects in those materials. Defects introduced into a material–for example, the placement of an impurity atom or molecule in the material’s structure–are often responsible for the material’s properties.

The group analyzed a monolayer hexagonal boron nitride sample prepared at Oxford University and was able to find and identify three types of atomic substitutions–carbon atoms substituting for boron, carbon substituting for nitrogen and oxygen substituting for nitrogen. Boron, carbon, nitrogen and oxygen have atomic numbers–or Z values– of five, six, seven and eight, respectively.

Armed with the high-resolution images, materials, chemical and nanoscience researchers and theorists can design more accurate computational simulations to predict the behavior of advanced materials, which are key to meeting research challenges that include energy storage and energy efficient technologies. (In other words, if we can actually see what it looks like, we can figure out how it all fits together!)

Individual boron and nitrogen atoms are clearly distinguished by their intensity in this Z-contrast scanning electron transmission microscope image from Oak Ridge National Laboratory. Each single hexagonal ring of the boron-nitrogen structure, for instance the one marked by the green circle in the figure a, consists of three brighter nitrogen atoms and three darker boron atoms. The lower (b) image is corrected for distortion. (Credit: Department of Energy, Oak Ridge National Laboratory)

Seeing a city, seeing a painting, seeing atoms. Our technology is showing us our world, as it’s never been seen before!

LASTING EFFECTS

By Pam Eastlick

Welcome to The Deep science and technology column where we cover topics from the deep sea to deep space and beyond.

Well, since ecology and environmental issues are much in the forefront in today’s news I figure it was time to discuss the oil spill. No, not THAT one; the other one!

IT’S IN THE WATER

Scientists in Alaska have discovered that oil from the 1989 Exxon Valdez spill is still being ingested by wildlife more than 20 years after the disaster. The research, published in Environmental Toxicology and Chemistry, uses biomarkers to reveal long-term exposure to oil in harlequin ducks and demonstrates how the consequences of oil spills are measured in decades rather than years.

The Exxon Valdez tanker ran aground on the Prince William Sound on March 24, 1989, spilling 10.8 million gallons of crude oil into the sea, covering 1,300 square miles. It is still regarded as one of the most devastating human-caused contamination events, and the effects on wildlife populations and communities have been debated by biologists, ecologists, and the oil industry ever since.

Now, using the biomarker CYP1A, which is induced when an animal is exposed to crude oil, an international team led by Daniel Esler, from the Centre for Wildlife Ecology, Simon Fraser University, British Columbia, has measured prolonged exposure to oil in local wildlife populations.

"One of the more remarkable and unanticipated findings of recent research is the length of time over which animals were exposed to residual oil," said Esler. "Our research has shown that oil remaining in the area, particularly in inter-tidal areas, was encountered and ingested by some near-shore animals."

The team focused their research on harlequin ducks as an example of such a species. Harlequins are marine birds that live in inter-tidal and shallow sub-tidal areas. Between 1990 and 2005 there were approximately 14,500 ducks in the Prince William Sound area.

"In addition to the higher likelihood of exposure due to their habitat, harlequin ducks have a number of characteristics that makes them particularly sensitive to oil pollution," said Esler. "Their diet consists of invertebrates that live in this area and have a limited ability to metabolize residual oil. Also, harlequin ducks have a life history strategy based on high survival rates, as well as a small body size when compared to other sea ducks."

"We found CYP1A levels were unequivocally higher in areas oiled by the Exxon Valdez spill than in nearby areas, a conclusion supported by multiple samples and two independent laboratories. We believe this shows harlequin ducks continued to be exposed to residual oil from the spill through at least 2009, twenty years after the event," concluded Esler. "We believe it is important to recognize that the duration of presence of residual oil and its associated effects are not limited to a few years after spills, but for some vulnerable species may occur over decades."

Now, let’s see. The Exxon Valdez spill was around 11 million gallons. The British Petroleum spill (notice that I know what ‘BP’ means even though the media seems to have forgotten) in the Gulf of Mexico has been spewing a MILLION GALLONS A DAY into the Gulf since it blew up on 20 April. That’s over 50 MILLION GALLONS since it started.

Of course, volume estimates vary with BP saying it’s ‘only’ 840,000 gallons per day and independent sources saying that it’s more like 1.7 million gallons per day, but the bottom line is that the Exxon Valdez spill was literally a drop in the bucket compared with what’s going on in the Gulf and there’s no end in sight.

So if we’re still dealing with the effects of the Exxon Valdez spill 20 years later, how much longer will it take for the effects of the Gulf oil spill to disappear? Fifty years? A hundred years?

The BP oil spill and the subsequent inability to stop it was an inevitable nightmare. The oil companies have always known that it was virtually impossible to stop a deep blow-out but they kept right on drilling anyway because we keep right on buying oil. It’s called “You’ve made your bed, now you get to lie in it.” And I’m just as guilty as you are!

So, let’s talk about something else and find someone else to blame. Have you noticed that sometimes here on Guam the air looks smoky or hazy? I’ve seen days here when it looked like Los Angeles smog. We have no heavy industry here and most all of our ‘air pollution’ produced mainly by the power plants, blows out to sea in the west. So where is all that ‘smog’ coming from? Short answer? China.

IT’S IN THE AIR

Scientists at the National Center for Atmospheric Research recently published a paper that says that pollutants from Asia are being blown into the stratosphere during monsoon season. The paper also gives additional evidence of the global nature of air pollution and its effects far above Earth’s surface.

Using satellite observations and computer models, the research team determined that vigorous summertime circulation patterns associated with the Asian monsoon rapidly transport air upward from the Earth’s surface. Those vertical movements provide a pathway for black carbon, sulfur dioxide, nitrogen oxides, and other pollutants to ascend into the stratosphere, about 20-25 miles above the Earth’s surface. Once in the stratosphere, the pollutants circulate around the globe for several years. Some eventually descend back into the lower atmosphere, while others break apart.

The study suggests that the impact of Asian pollutants on the stratosphere may increase in coming decades because of the growing industrial activity in China and other rapidly developing nations. In addition, climate change could alter the Asian monsoon, although it remains uncertain whether the result would be to strengthen or weaken vertical movements of air that transport pollutants into the stratosphere.

When sulfur rises into the stratosphere, it can lead to the creation of small particles called aerosols that are known to influence the ozone layer. The monsoon transport pathway may also have effects on other gases in the stratosphere, such as water vapor, that affect global climate by influencing the amount of solar heat that reaches Earth.

Scientists have long known that air over the tropics moves upward between the lower atmosphere and the stratosphere, part of a large-scale pattern known as the Brewer-Dobson circulation. But the monsoon might also transport air into the stratosphere during the Northern Hemisphere’s summer months. This could explain satellite measurements showing anomalous levels of stratospheric ozone, water vapor, and other chemicals over Asia during summer.

To isolate the role of the monsoon on the stratosphere, the researchers focused on hydrogen cyanide, which is produced largely as a result of the burning of trees and other vegetation. The parcels of air over the tropical ocean that are lifted to the stratosphere by the Brewer-Dobson circulation contain low amounts of hydrogen cyanide, which breaks up over the ocean. But air over land that gets lifted up by the monsoon contains high levels of the chemical, especially during times of year when Asia has widespread fires, many set to clear land for agriculture.

When they examined satellite measurements, the researchers detected significant amounts of hydrogen cyanide throughout the lower atmosphere and up into the stratosphere over the monsoon region. Furthermore, satellite records from 2004 to 2009 showed a pattern of increases in the chemical’s presence in the stratosphere each summer, correlating with the timing of the monsoon. The observations also showed hydrogen cyanide, which can last in the atmosphere for several years before breaking up, moving over the tropics with other pollutants and then circulating globally.

The researchers then used computer modeling to simulate the movement of hydrogen cyanide and pollutants from other sources, including industrial activity. The model indicated that emissions of pollutants over a broad region of Asia, from India to China and Indonesia, were becoming entrained in the monsoon circulation and transported into the lower stratosphere.

Factories line the shores of the lower Yangtze River in China. Heavy pollution tied to China’s rapid industrial growth has produced poor visibility and health effects. (Credit: Copyright UCAR, Photo by William Bradford)

We actually get some of our Chinese pollution in a far more direct manner. Sometime you can see clouds of the stuff on the satellite map blowing down from the northwest. It really is one big planet, ladies and gentlemen and what goes around comes around!

So are you thoroughly depressed yet? Let’s leave pollution behind and do a follow-up story on one of our recently discussed creepy animals.

THEY’RE IN THE BONES?

You may remember my story a couple of weeks ago about boneworms, bizarre animals that spend their entire lives in and feasting on the bones of dead whales. In that story, I reported that scientists were uncertain about how long boneworms had been around.

Well, the definitive answer isn’t in yet, but an international team of scientists has found the first fossil boreholes of the worm Osedax that consumes whale bones on the deep-sea floor and they conclude that "boneworms" are at least 30 million years old. To get accurate images of the fossil boreholes, the scientists did CT scans on the bones.

The fossils belong to ancestors of modern baleen whales and their age coincides with the time when whales began to inhabit the open ocean. When they died they sank to the deep-sea floor where they served as food for the boneworms.

Finding that boneworms existed that long ago may also solve a paleontological mystery. Fossil whales are relatively rare in the fossil record and the fact that Osedax has been around that long, just could be the reason!

This 30 million year old rib fragment of a whale shows the circular boreholes (diameter: 0,5 mm) made by Osedax. (Credit: Copyright Uni Kiel)

Pollution, pollution and boneworms. Here’s hoping all this pollution doesn’t eliminate US from the fossil record!