[越毒] 吴月叁阅读小犬总结（共68只，更新:6/3 10：58）

yangmars

google到的一篇月读 臭氧空洞 full covery 的后果的文章，跟裤子中1,21，应该是差不多的，
A full recovery of the stratospheric ozone hole could modify climate change in the Southern Hemisphere and even amplify Antarctic warming, according to scientists from the University of Colorado at Boulder, the National Oceanic and Atmospheric Administration and NASA.

While Earth's average surface temperatures have been increasing, the interior of Antarctica has exhibited a unique cooling trend during the austral summer and fall caused by ozone depletion, said Judith Perlwitz of the Cooperative Institute for Research in Environmental Sciences, a joint institute of CU-Boulder and NOAA. "If the successful control of ozone-depleting substances allows for a full recovery of the ozone hole over Antarctica, we may finally see the interior of Antarctica begin to warm with the rest of the world," Perlwitz said.

Perlwitz is lead author of a new study on the subject to be published April 26 in Geophysical Research Letters. Co-authors include Steven Pawson and Eric Nielson of NASA's Goddard Space Flight Center in Greenbelt, Md., and Ryan Fogt and William Neff of NOAA's Earth System Research Laboratory in Boulder. The study was supported by NASA's Modeling and Analysis Program.

The authors used a NASA supercomputer model that included interactions between the climate and stratospheric ozone chemistry to examine how changes in the ozone hole influence climate and weather near Earth's surface, said Perlwitz.

The study authors calculated that when stratospheric ozone levels return to near pre-1969 levels by the end of the 21st century, large-scale atmospheric circulation patterns now shielding the Antarctic interior from warmer air masses to the north will begin to break down during the austral summer. The circulation patterns are collectively known as a positive phase of the Southern Annular Mode, or SAM.

The scientists found that as ozone levels recover, the lower stratosphere over the polar region will absorb more harmful ultraviolet radiation from the sun. This could cause air temperatures roughly 6 to 12 miles above Earth's surface to rise by as much as 16 degrees Fahrenheit, reducing the strong north-south temperature gradient that currently favors the positive phase of SAM, said the research team.

The supercomputer modeling effort also indicated that ozone hole recovery would weaken the intense westerly winds that currently whip around Antarctica and block air masses from crossing into the continent's interior. As a result, Antarctica would no longer be isolated from the warming patterns affecting the rest of the world.

NASA's Pawson said ozone recovery over Antarctica would essentially reverse summertime climate and atmospheric circulation changes that have been caused by the presence of the ozone hole. "It appears that ozone-induced climate change occurred quickly, over 20 to 30 years, in response to the rapid onset of the ozone hole," he said. "These seasonal changes will decay more slowly than they built up, since it takes longer to cleanse the stratosphere of ozone-depleting gases than it took for them to build up."

The seasonal shift in large-scale circulation patterns could have repercussions for Australia and South America as well. Other studies have shown that the positive phase of SAM is associated with cooler temperatures over much of Australia and increased rainfall over Australia's southeast coastline.

During late spring and early summer, the positive phase of SAM also is associated with drier conditions in South America's productive agricultural areas like Argentina, Brazil, Uruguay and Paraguay, said Perlwitz. If ozone recovery induces a shift away from a positive SAM, Australia could experience warmer and drier conditions while South America could get wetter, she said.

But just how influential a full stratospheric ozone recovery will be on Southern Hemisphere climate largely depends on the future rate of greenhouse gas emissions, according to the GRL authors. Projected increases in human-emitted greenhouse gases like carbon dioxide will be the main driver for strengthening the positive phase of SAM.

"In running our model simulations, we assumed that greenhouse gases like carbon dioxide would double over the next 40 years and then slowly level off," said Perlwitz. "If human activities cause more rapid increases in greenhouse gases, or if we continue to produce these gases for a longer period of time, then the positive SAM may dominate year-round and dwarf any climatic effects caused by ozone recovery."

NASA's High-End Computing Program provided the Columbia supercomputer resources at the NASA Ames Research Center in Moffett Field, Calif.

amber8960

回复ls....那个不赖lz....
我考古的时候....没贴上highlight= =
注意highlight的部分
Interestingly— orunnervingly, depending on how you look at it —  some researchers are uncovering evidencethat Stanovnik’s rule of  thumb might be right. A spate ofrecent studies has contributed to  growing support for the notion that theorigins and controls of  fatigue lie partly, if not mostly, within thebrain and the central  nervous system. The new research puts fresh weightto the hoary  coaching cliché: you only think you’re tired.From the timeof Hippocrates, the limits of human exertion were  thought to reside inthe muscles themselves, a hypothesis that was  established in 1922 withthe Nobel Prize-winning work of Dr. A.V.  Hill. The theory went like this:working muscles, pushed to their  limit, accumulated lactic acid. When concentrations of lactic acid  reached acertain level, so the argument went, the muscles could no  longerfunction. Muscles contained an ‘‘automatic brake,’’  Hill wrote, ‘‘carefully adjusted by nature.’’Researchers, however, have long noted a linkbetween neurological  disorders and athletic potential.’’Questions about the muscle-centered model came up again in 1989 when Canadian researchers published the results of an experiment called Operation Everest II, in which athletes did heavy exercise in  altitudechambers. The athletes reached exhaustion despite the fact  that theirlactic-acid concentrations remained comfortably low.  Fatigue, it seemed,might be caused by something else.In 1999, three physiologists from theUniversity of Cape Town Medical  School in South Africa took the nextstep. They worked a group of  cyclists to exhaustion during a 62-milelaboratory ride and measured,  via electrodes, the percentage of legmuscles they were using at the  fatigue limit. If standard theories weretrue, they reasoned, the  body should recruit more muscle fibers as itapproached exhaustion —  a natural compensation for tired, weakeningmuscles.Instead, the researchers observed the opposite result. As theriders  approached complete fatigue, the percentage of active musclefibers  decreased, until they were using only about 30 percent. Even asthe  athletes felt they were giving their all, the reality was thatmore  of their muscles were at rest. Was the brain purposely holding back  thebody?‘‘It was as ifthe brain was playing a trick on the body, to save  it,’’ says Timothy Noakes, head of the Cape Towngroup.  ‘‘Which makes a lot of sense, if you think about it.In fatigue,  it only feels like we’re going to die. The actual physiological risks that fatigue represents are essentially trivial.’’From this, Noakes and his colleagues concluded that A.V. Hill had been right about the automatic brake, but wrong about its location. They postulated the existence of what they calleda central governor: aneural system that monitors carbohydrate stores, the levels of  glucoseand oxygen in the blood, the rates of heat gain and loss, and  work rates.The governor’s job is to hold our bodies safely back  fromthe brink of collapse by creating painful sensations that we  interpret asunendurable muscle fatigue.Fatigue, the researchers argue, is less anobjective event than a  subjective emotion — the brain’s clever, self-interested attempt  to scareyou into stopping. ‘‘It’s notthat they don’t feelthe pain; they just shift  their brain dynamics and alter their perceptionof reality so the  pain matters less. It’s basically a purposeful hallucination.’’Noakes and his colleagues speculate that the central governor theory holds the potential to explain not just feats of stamina but also  theiropposite: chronic fatigue syndrome (a malfunctioning,  overactivegovernor, in this view). Moreover,the governor theory  makes evolutionary sense. Animals whose brainssafeguarded an  emergency stash of physical reserves might well havesurvived at a  higher rate than animals that could drain their fuel tanksat will.The theory would also seem to explain a sports landscape in which ultra-endurance events have gone from being considered medically hazardous to something perilously close to routine. The Ironman  triathlonin Hawaii — a 2.4-mile swim, 112-mile bike ride and marathon-length run — was the ne plus ultra in endurance in the 1980’s, but hasnow been topped by the Ultraman, which is more than  twice as long. Onceobscure, the genre known as adventure racing,  which includes500-plus-mile wilderness races like Primal Quest, has  grown to more than400 events each year. Ultramarathoners, defined as  those who participatein running events exceeding the official  marathon distance of 26.2 miles,now number some 15,000 in the United  States alone. The underlying physicshave not changed, but rather our  sense of possibility. Athletic culture,like Robic, has discovered a  way to tweak its collective governor.

-- by 会员 WuApril (2011/5/13 9:24:19)

谢谢小丸子 十分感激！

百事薯片

谢楼主~~~~

Ginger儿

这个文件的观点和JJ差不多，可以参考http://www.ftc.gov/speeches/majoras/070326munich.pdf

1.7.5公司之间的竞争goverment应该采取怎样的做法
一些经济学家通常认为，domestic中的industry的competition通常会导致一些缺点。。。因此goverment应该做的是组成一个champion，来一起努力应对international competition。但，事实上这些champion往往不会让这个国家的该产业在与国外公司的竞争中取得优势，因为国内产业的竞争会逼着这些公司降低成本，增加自己的竞争力，这样再到国外竞争时才会有更强的竞争力。
文章不难，有点小长，不过只要记住作者是支持国内的竞争就可以了~~~

rosaaa

bingjingbuna

谢谢分享

chasingM7

dddddddddddddddddddddddddddddddddddd...

jeanq

谢谢小丸子！！一起加油！

tammy212

。

tammy212

1.2.6和1.1.3是一篇文章啊，可以合并吧。。。