Some sentences below, are from a Wired article about dust storms in the American southwest, which recently saw a rare 100 mile wide dust storm that got lots of publicity even in a season marked by weather extremes. The article concludes with an intriguing geological feature that is little known, called "biological soil crusts," which feature of the terrain is utterly delicate and yet resistant to drought.
In January,...the United States Geological Survey released the results of a 20 year-long survey...[about] relationships between temperature, vegetation and soil loss on the Colorado Plateau, a region spanning Utah, New Mexico, Colorado and Arizona. They found that higher temperatures reduce plant density, which in turn removes roots that hold soil together. [And so we could expect]... increased wind erosion and dust emission on the Colorado Plateau...[Surprising help may come from another discovery]
The researchers also found that so-called biological soil crusts, a little-studied layer of lichen and bacteria found in arid western regions, play a surprisingly large role in preventing erosion. Just a few millimeters thick, these crusts are extraordinarily sensitive, and can take decades to recover from a mere footprint. They’re also widely compromised by livestock, off-road vehicles and mining.
But in one important way, biological soil crusts are pwerfully resilient. The researchers found them to be mostly unaffected by changes in temperature and rainfall. If the crusts can be protected, a 21st century Dust Bowl might be averted.
Tuesday, July 12, 2011
Sunday, July 10, 2011
Headlines We Like
Psychiatric disorders: The dark side of depression
FROM: Nature Reviews Nwueoscience
Psychiatric disorders: The dark side of depressionp435 | doi:10.1038/nrn3072Immune factors mediate the effect of circadian disruption on depression-like behaviour
exaxct heading to their newsletter review is
Psychiatric disorders: The dark side of depression
p435 | doi:10.1038/nrn3072
Immune factors mediate the effect of circadian disruption on depression-like behaviour
Personality Disorders to Be Cut
from the BigThink newsletter of July 10, 2011 (info@bigthink.com):
| Several types of personality disorders will be dropped from the next edition of the Diagnostic and Statistical Manual of Mental Disorders. But narcissistic personality disorder will remain. |
As The World Wobbles
An interesting article is in The Telegraph (co.uk) about the tabloid phone hacking case that is now --July, 2011, -- dominating the British headlines. I do not know if decades from now the current scandal will be seen as a forgotten chapter in the history of media, or a date cluster indicating some turning point in the history of corporate power and democracy. I doubt much improvement will result from the current news about scandals in the news. The article talks about a multi-millionaire who is bankrolling poor people who have been damaged by the phone hacking, like, some families who had members die in subway bombings. He does this by guaranteeing their court costs should their law suits against the Murdoch papers fail. Is Mosley interested in promoting media fairness?
The startling story that rates placement in this blog is Mosley's motives. The tabloid now in the headlines published a story about him some years ago, a story about sex, and he sued them, got damages, and has been carrying on a vendetta since. So its rich people vs. rich people. And if his name is familiar, Mosley's father was the leading British fascist during the thirties and forties --Oswald Mosley.
The startling story that rates placement in this blog is Mosley's motives. The tabloid now in the headlines published a story about him some years ago, a story about sex, and he sued them, got damages, and has been carrying on a vendetta since. So its rich people vs. rich people. And if his name is familiar, Mosley's father was the leading British fascist during the thirties and forties --Oswald Mosley.
Friday, July 1, 2011
Model Breaking Records
Model Breaking Records
That quasar in the news because of its distance/young age presents puzzles for cosmologists, and here is a nice summary from skyandtelescope.com, of the models and why they don't seem to fit. Although the quasar's distance is record setting, the blogger Shweta Krishnan reminds us, also, that the:
Quasar ....is not, however, the most distant object known in the deep sky. A gamma-ray burst has been identified at a redshift of 8.2, and a galaxy at a redshift of 8.6....The following are her words also--
....
The Conundrum within the Quasar
While the discovery offers unprecedented opportunities, it also presents a quandary in the form of the monstrous black hole that powers the quasar.
There are two dominant models of black-hole formation. A star the mass of 10-100 suns can go supernova to spawn these structures. A second theory suggests that accreting clumps of gases can directly undergo core collapse to generate supermassive black holes.
But both these models fail to explain how such an early black hole reached the mass of two billion suns. One possible explanation is a rapidly growing black hole that developed from the explosion of a star the size of half a million suns. But current theories cannot account for a star that size in the early universe. The same is true for large collapsing gas cores.
"This gives astronomers a headache," says Mortlock. "It's difficult to understand how a black hole a billion times more massive than the Sun can have grown so early in the history of the universe. It's like rolling a snowball down the hill and suddenly you find that it's 20 feet across!"
...
Black Hole theorist Priyamvada Natarajan (University of Yale), who spearheaded the model on self-regulating black holes, said that the discovery was exciting for the same reasons that it was challenging. She emphasized the need to find more giant black holes in order to come up with better models in the future. “The finding of a population is key to theoretical understanding (because) we can always come up with explanations for single rare objects, but to explain a population you need a robust mechanism.”
That quasar in the news because of its distance/young age presents puzzles for cosmologists, and here is a nice summary from skyandtelescope.com, of the models and why they don't seem to fit. Although the quasar's distance is record setting, the blogger Shweta Krishnan reminds us, also, that the:
Quasar ....is not, however, the most distant object known in the deep sky. A gamma-ray burst has been identified at a redshift of 8.2, and a galaxy at a redshift of 8.6....The following are her words also--
....
The Conundrum within the Quasar
While the discovery offers unprecedented opportunities, it also presents a quandary in the form of the monstrous black hole that powers the quasar.
There are two dominant models of black-hole formation. A star the mass of 10-100 suns can go supernova to spawn these structures. A second theory suggests that accreting clumps of gases can directly undergo core collapse to generate supermassive black holes.
But both these models fail to explain how such an early black hole reached the mass of two billion suns. One possible explanation is a rapidly growing black hole that developed from the explosion of a star the size of half a million suns. But current theories cannot account for a star that size in the early universe. The same is true for large collapsing gas cores.
"This gives astronomers a headache," says Mortlock. "It's difficult to understand how a black hole a billion times more massive than the Sun can have grown so early in the history of the universe. It's like rolling a snowball down the hill and suddenly you find that it's 20 feet across!"
...
Black Hole theorist Priyamvada Natarajan (University of Yale), who spearheaded the model on self-regulating black holes, said that the discovery was exciting for the same reasons that it was challenging. She emphasized the need to find more giant black holes in order to come up with better models in the future. “The finding of a population is key to theoretical understanding (because) we can always come up with explanations for single rare objects, but to explain a population you need a robust mechanism.”
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