This image shows a colour-coded representation of ultra-relativistic electron fluxes
High above Earth’s atmosphere, electrons whiz past at close to the speed of light. Such ultrarelativistic electrons, which make up the outer band of the Van Allen radiation belt, can streak around the planet in a mere five minutes, bombarding anything in their path. Exposure to such high-energy radiation can wreak havoc on satellite electronics, and pose serious health risks to astronauts.
Now researchers at MIT, the University of Colorado, and elsewhere have found there’s a hard limit to how close ultrarelativistic electrons can get to the Earth. The team found that no matter where these electrons are circling around the planet’s equator, they can get no further than about 11,000 kilometres (6,800 miles) from the Earth’s surface – despite their intense energy.
What’s keeping this high-energy radiation at bay seems to be neither the Earth’s magnetic field nor long-range radio waves, but rather a phenomenon termed “plasmaspheric hiss” – very low-frequency electromagnetic waves in the Earth’s upper atmosphere that, when played through a speaker, resemble static, or white noise…
The team’s results are based on data collected by NASA’s Van Allen probes – twin crafts that are orbiting within the harsh environments of the Van Allen radiation belts. Each probe is designed to withstand constant radiation bombardment in order to measure the behaviour of high-energy electrons in space…
Instead, the group found that the natural barrier may be due to a balance between the electrons’ slow, earthward motion, and plasmaspheric hiss. This conclusion was based on the Van Allen probes’ measurement of electrons’ pitch angle – the degree to which an electron’s motion is parallel or perpendicular to the Earth’s magnetic field. The researchers found that plasmaspheric hiss acts slowly to rotate electrons’ paths, causing them to fall, parallel to a magnetic field line, into Earth’s upper atmosphere, where they are likely to collide with neutral atoms and disappear.
Useful for anyone up for near-Earth space research. One of the crappiest military/political notes in the research is a discussion of nuclear warheads that US military detonated in space to play with using artificially-created radiation belts to blind other nation’s satellites.
I guess we’re lucky once again to have survived War Department experiments which had a potential failure forecast which might have turned us all into mutants glowing in the dark.
Human-induced changes to Earth’s carbon cycle — for example, rising atmospheric carbon dioxide and ocean acidification — have been observed for decades. However, a study published this week in Science showed human activities, in particular industrial and agricultural processes, have also had significant impacts on the upper ocean nitrogen cycle.
The rate of deposition of reactive nitrogen (i.e., nitrogen oxides from fossil fuel burning and ammonia compounds from fertilizer use) from the atmosphere to the open ocean has more than doubled globally over the last 100 years. This anthropogenic addition of nitrogen has reached a magnitude comparable to about half of global ocean nitrogen fixation (the natural process by which atmospheric nitrogen gas becomes a useful nutrient for organisms). David Karl…teamed up with researchers from Korea, Switzerland and…NOAA…to assess changes in nitrate concentration between the 1960s and 2000s across the open North Pacific Ocean.
Their analysis, which could discern human-derived nitrogen from natural nitrogen fixation, revealed that the oceanic nitrate concentration increased significantly over the last 30 years in surface waters of the North Pacific due largely to the enhanced deposition of nitrogen from the atmosphere.
“This is a sobering result, one that I would not have predicted,” said Karl. “The North Pacific is so vast it is hard to imagine that humans could impact the natural nitrogen cycle.”
…Their assessment revealed a consistent picture of increasing nitrate concentrations, the magnitude and pattern of which can only be explained by the observed increase in atmospheric nitrogen deposition.
Enhanced nitrogen deposition has several potential ecological ramifications. Because biological activity is limited by nitrate availability in the North Pacific Ocean, the input of new nitrogen from the atmosphere may increase photosysnthesis in the sunlit layers and export of carbon-rich organic material out of the surface ocean into the deep.
“The burgeoning human population needs energy and food — unfortunately, nitrogen pollution is an unintended consequence and not even the open ocean is immune from our daily industrial activities,” said Karl.
Given the likelihood that the magnitude of atmospheric nitrogen deposition will continue to increase in the future, the North Pacific Ocean could rapidly switch to having surplus nitrate. Thus, past and future increases in atmospheric nitrogen deposition have the potential to alter the base of the marine food web; and, in the long term, the structure of the ecosystem.
…If similar trends are confirmed in the Atlantic and Indian Oceans, it would constitute another example of a global-scale alteration of Earth system. Further, the findings of this study of the North Pacific highlight the need for greater controls on the emission of nitrogen compounds during combustion and agricultural processes.
The short answer is – if we don’t succeed in wresting control of the politics and power of our nation from the Know-Nothings – we’re screwed. We will be no different from fishes swimming in a steadily heated cauldron until they are killed and cooked. And the Koch Bros, the John Boehners and Rand Pauls of our political world ain’t even dropping in some onions and garlic to make our end a savory one.
We love our dogs.
In the 30,000 years humans and dogs have lived together, man’s best friend has only become a more popular and beloved pet. Today, dogs are a fixture in almost 50% of American households.
From the way dogs thump their tails, invade our laps and steal our pillows, it certainly seems like they love us back. But since dogs can’t tell us what’s going on inside their furry heads, can we ever be sure?
Actually, yes. Thanks to recent developments in brain imaging technology, we’re starting to get a better picture of the happenings inside the canine cranium.
That’s right — scientists are actually studying the brains of dogs. And what the studies show is welcome news for all dog owners: Not only do dogs seem to love us back, they actually see us as their family. It turns out that dogs rely on humans more than they do their own kind for affection, protection and everything in between.
The most direct brain-based evidence that dogs are hopelessly devoted to humans comes from a recent neuroimaging study about odor processing in the dog brain. Animal cognition scientists at Emory University trained dogs to lie still in an MRI machine and used fMRI (functional magnetic resonance imaging) to measure their neural responses to the smell of people and dogs, both familiar and unknown. Because dogs navigate the world through their noses, the way they process smell offers a lot of potential insight into social behavior.
The scientists found that dog owners’ aroma actually sparked activation in the “reward center” of their brains, called the caudate nucleus. Of all the wafting smells to take in, dogs actually prioritized the hint of humans over anything or anyone else.
Read the rest at the original article. Delightful study, especially – I guess – because it reassures what humans like me feel goes back to the time when we shared our caves with our dogs. And all the way up to and including our modern dwellings. Especially when it feels like the house and furnishings belong to the dog as much as anyone else.
Well, at least in our house.
Although maize was originally domesticated in Mexico, the country’s average yield per hectare is 38% below the world’s average. In fact, Mexico imports 30% of its maize from foreign sources to keep up with internal demand.
To combat insect pests, Mexican farmers rely primarily on chemical insecticides. Approximately 3,000 tons of active ingredient are used each year just to manage the fall armyworm (Spodoptera frugiperda), in addition to even more chemicals used to control other pests such as the corn earworm (Helicoverpa zea) and the black cutworm (Agrotis ipsilon). Because of the severity of these pests and the reliance on chemical insecticides, Mexico uses the highest quantity of pesticides per hectare of arable land in North America.
While integrated pest management (IPM) programs — which aim to minimize economic damage and lower environmental and health risks — are widely used in crops such as tomatoes, broccoli, and peppers, IPM is highly uncommon in Mexican maize crops…
The authors found the diversity of growing conditions to be the greatest obstacle for implementing IPM programs for Mexico’s 2 million growers, many of whose fields are only two hectares or less.
Another obstacle, according to the authors, is the lack of insect-resistant maize varieties, such as Bt hybrids. These varieties, which are genetically modified to express proteins from the bacterium Bacillus thuringiensis, are grown on 90 percent of maize fields in the U.S., whose yields per hectare are nearly three times greater than Mexican yields.
“According to our estimates, 3,000 tons of organophosphate active ingredient is sold in Mexico each year to control ONLY fall armyworm, ONLY on corn,” said Professor Urbano Nava-Camberos of the Universidad Juárez del Estado de Durango, and one of the co-authors. “In addition, applications are also made to cutworms, corn rootworms, borers, and corn earworms that do not necessarily coincide with the fall armyworm applications. However, all of these insect pests can be effectively controlled with Bt corn and integrated pest management programs.”
“There are a few solutions that can be immediately implemented to diminish the environmental impact of corn pests, including the use of Bt corn,” added another co-author, crop consultant Guadalupe Pellegaud. “Unfortunately, people who oppose the introduction of this technology in Mexico do not seem to realize that a far greater environmental impact is done by applying more than 3,000 tons of insecticide active ingredient each year.”
The full open-access article, “Maize Pests in Mexico and Challenges for the Adoption of Integrated Pest Management Programs“, is available as a freebie. If you can find your way through a website designed by entomologists.
Concentrations of greenhouse gas in the atmosphere continue to increase. On Monday, NASA released a striking video that visualizes the invisible gas as it travels around the planet over one year.
The simulation shows plumes of carbon dioxide “swirl and shift as winds disperse the greenhouse gas away from its sources,” according to NASA. The video also shows differences in carbon dioxide levels in the Northern and Southern hemispheres, as well as the change in concentrations of carbon dioxide that come with changes in season due to the growth cycle of plants and trees.
Created with an ultra-high-resolution computer model, the visualization is called “Nature Run,” simulating May 2005 to June 2007.
“The Nature Run ingests real data on atmospheric conditions and the emission of greenhouse gases and both natural and man-made particulates,” NASA wrote. “The model is then is left to run on its own and simulate the natural behavior of the Earth’s atmosphere.”
Computational analysis is fundamental to growing and understanding modern science. I admit it. I love it.
What a fascinating tool.
Using some antibacterial soaps may promote tumor growth, according to a study just published in Proceedings of the National Academy of Sciences. The findings add to a body of concerns about triclosan, one of the most common antimicrobial chemicals in consumer products from detergents to cosmetics, including links to allergy development in children, and potentially to breast cancer via disruption of hormone signals that may also cause thyroid dysfunction and weight gain.
Triclosan is regulated in many countries, but the U.S. isn’t among them. In 1974 the Food and Drug Administration (FDA) proposed a ruling on the safety of triclosan; but, four years later, the agency said that was not possible due to insufficient evidence. In 2010, still with no FDA ruling, the National Resources Defense Council sued the FDA over the matter. Still today there’s no ruling, but the FDA has said that it will commit to something by 2016. The chemical is in an estimated 75 percent of antimicrobial soaps and body washes, though some companies have begun voluntarily phasing it out due to health concerns. Products like Johnson’s baby shampoo and Palmolive no longer contain triclosan.
Still a study in August from the University of California, San Francisco, found that about three-fourths of doctors and nurses had triclosan in their urine, and another study earlier this year found triclosan in the urine of 100 percent of pregnant women tested in Brooklyn. Because triclosan-infused products have been so widely used for many years, exposure to the chemical entirely is unavoidable. It is among the most common chemicals to be detected in streams.
“The result that it led to liver fibrosis was startling to us,” lead researcher Robert Tukey said. The researchers also noted a similar effect in kidneys. Their findings suggest that triclosan does not cause liver tumors by itself, in that it does not mutate DNA. But it does promote tumor formation once a mutation has occurred. Liver cancer (hepatocellular carcinoma, specifically) is the world’s number-three cause of cancer death.
“If non-triclosan-containing soaps are available, use the alternative,” said Paul Blanc, a professor of medicine at UCSF, earlier this year in a press statement. “This is based on the precautionary principle–that is, if you don’t know for certain that something is unsafe, it’s better to err on the side of caution.”
No one is saying triclosan causes cancer. It just promotes an environment that aids the growth of tumors. Whoop-de-doo! Not a big difference for ordinary folks who acquire liver cancer.
Americans have a lifetime exposure to propaganda – called commercials – that say there always is a magic ingredient that cures everything wrong in your life. It may be soap, it may be beer. It may be where you bank, it may be which old white guy will guarantee to keep your political life all snug and unchanging. And it’s mostly bullshit!
There are plenty of reasonable if dull sources for information about health. If you can, try to stay away from the quacks. Try to avoid the folks selling you snake oil. I sometimes feel that any solution that sounds extra easy has to be wrong – or at least less reliable. Anti-bacterial soap is one of those.
Designed to kill off critters instead of the awesome labor of scrubbing them away with soap and hot water – doctors and nurses are as guilty of being misled as the rest of us. The medical-industrial complex – predictably – uses their success at selling crap products to the medical community to sell them to us. We get to see pictures of folks in white starched coats smiling while they endorse mutation-enhancing products.
Keep on rocking in the Free World.
The chemicals found in fracking fluid collected in five states — including Colorado — were no more toxic than common household substances, according to a newly released study by researchers at the University of Colorado.
The study…found that chemicals in the fracking fluid samples also were found in everyday products such as toothpaste, detergent, ice cream and laxatives.
Michael Thurman…said, “At least so far, we’re finding chemicals that are more friendly to the environment,” Thurman said. “The compounds are not the kinds of things we consider toxic.”
The study examined samples from Colorado, Nevada, Louisiana, Pennsylvania and Texas. According to the researchers, fracking fluid is comprised mostly of water and sand, but oil and gas companies add a variety of other chemicals such as anti-bacterial agents, corrosion inhibitors and surfactants — chemicals that reduce the surface tension between water and oil…
There have been concerns about the chemicals used by oil and gas companies in fracking. Recent state and federal regulations require companies to disclose what is being used in their fracking fluids, but companies typically use broad chemical categories to describe the actual ingredients to avoid revealing what they consider proprietary information.
The researchers cautioned that individual well operators might use different chemicals based on location, and said there are still other concerns about fracking, including air pollution, the antimicrobial biocides used in fracking fluids, wastewater disposal triggering earthquakes and the large amount of water used.
But Thurman said water pollution from surfactants in fracking fluid may not be as concerning as some people had thought, with the really toxic surfactants, such as endocrine disruptors, not being used in the wells that were tested.
“Not finding those chemicals is really important,” he said.
Thurman said he plans to continue analyzing the surfactants used in fracking and wants to look at more samples to determine if those he identified in the study are in fact used widely. If they are, he said, they could be used as markers to determine if a well or other groundwater source has been contaminated by fracking fluid.
A pleasant surprise. Well drillers are gunshy because of the number of times they’ve been caught and found guilty of environmental degradation. They’ve actually increased the perception of wrongdoing by their secrecy fetish.
I’ve worried less about the process of fracking than most of my enviro peers because I have at least a minimal comprehensions of geology. Looking at aquifers here in Santa Fe County I get lots of chuckles from panic-stricken water dweebs who don’t know what an aquifer really is, how many we have in the region and how thoroughly they are separated. Plus – I admit – I’m a little smug from living at the dead end of the major Ancha aquifer – watching the water table rise because everyone upstream is diligently working at using less water. :)
The most important points Michael Thurman raises remain – and should guide opposition to more oil well-drilling in general – especially air pollution, wastewater disposal triggering earthquakes and the large amount of water used. Methane is going to continue to work its way into the atmosphere from every kind of oil well/oil field on the planet. Most of the industry’s production is from fields with lower standards than the United States. And you might remember that we’re only 6% of the land mass on the planet.
The fight against fossil fuel has to be planet-wide – and dedicated. Not just this election cycle – not just because the Blue Meanie Republicans are obedient pawns of the Oil Patch Boys.
Collateral damage – from Mike’s research: Sioux Nations oppose Keystone XL pipeline.
Researchers describe the scent coming off 67P/Churyumov-Gerasimenko as reminiscent of rotten eggs and a horse stable.
They had outfitted Rosetta with a sort of artificial nose — an instrument called ROSINA — that can analyze gas vapors and replicate smell. Among other trace chemicals, Chury offers a powerful punch of hydrogen sulfide, ammonia, formaldehyde and hydrogen cyanide.
The strong presence of rotten egg (hydrogen sulfide) and horse stable (ammonia) smells are accented by notes of alcohol (methane) and vinegar (sulfur dioxide). In case that wasn’t gross enough, the hyrdogen cyanide and carbon disulfide offer a hint of sugared almonds.
Researchers say it’s the first time they’ve really gotten a good whiff of a comet.
“We’ve never been that close to a comet,” Kathrin Altwegg, the researcher who manages the ROSINA instrument from a lab at the University of Bern in Switzerland…
The comet — which Rosetta tried to anchor to with the exploratory craft called Philae — is 250 million miles from the sun. But it’s getting closer. And that’s bad news for astronomers with a weak stomach.
“The closer the comet gets to the sun, the more of its ice will evaporate, and the gas emissions will get more intense,” Altwegg explained to Deutsche Welle.
Sounds like the next time Earthlings sneak up on a comet and land on it to research its composition – we might include a little gas-powered engine in addition to solar panels to power the research vehicle. Something that runs on horse farts.
[Adapted from an article published just before Philae landed on 67P]
Impossible Foods CEO and Co-Founder Patrick Brown discusses his company’s products which are made entirely from plants, creating a sustainable source of food and why he says his products are made a better way — with Bloomberg’s Angie Lau on “First Up.”
Amazing what computational analysis and genetic engineering are getting ready to make possible. I have a couple of old acquaintances – retired molecular biologists – who probably would like to start all over again.
Lightning strikes in the lower 48 U.S. states will increase about 12% for every degree rise in Earth’s average temperature, potentially sparking more wildfires, according to a new study.
The new estimate was based on calculations of convective energy and precipitation from future thunderstorms, and fits three independent data sets chronicling past strikes, according to the study, published online Thursday in the journal Science.
“You need two ingredients to make lightning in a storm,” said the study’s lead investigator, David Romps, a climate scientist at UC Berkeley. “One of those is that you have water in its three phases — vapor, liquid and ice — coexisting in the cloud. And the other is that the storm clouds be rising quickly enough to loft that liquid and ice into the atmosphere and keep it suspended. So we’ve built our proxy around those two ideas.”
Previous formulas were built around predicted cloud heights and did not account for as much of the variance in actual strikes as the new proxy does, according to the study. The new proxy explains about 77% of the variance in strikes.
It’s only conjecture; but, you would have to think an increase in lightning strikes will forge an equivalent rise in the number of wildfires – lightning causing about half of all wildfires. Not a feature of climate change that anyone in mountain and forest country looks forward to.