关于地月的yd，我发现一个非常接近于大家的寂静的英文文章

kiki070300123 · 发表于 2011-11-19 18:07:20

不知道有木用先贴出来
The moon's origin has been the subject of scientific speculation since Galileo in 1609 showed that the moon is a rocky body like our earth. Just before the Apollo landings began in 1969 there were three different theories of its origin: The fission theory, proposed by G. H. Darwin, Charles Darwin's son, supposed that the moon was spun out of the earth's mantle during an early era of rapid rotation of the ancient earth. The capture theory supposed that the moon formed somewhere else in the solar system and was later captured in orbit about the earth. The co-accretion or "double planet" theory supposed that the earth and moon simply grew together out of a primordial swarm of small "planetesimals". When confronted with the evidence of the lunar rocks, none of these three theories could be confirmed--all made predictions at variance with the observations that the moon has no substantial metallic iron core, that its rocks are grossly similar in composition to the earth's mantle (its oxygen isotopic ratios are identical to the earth's), but that the lunar rocks are slightly enriched in refractory elements and are strongly depleted in volatiles. This disagreement was resolved in 1984 when a new theory of the moon's origin began to gain attention. The new theory stemmed from the recognition that the early solar system 4,500 million years ago was a more violent place than had been previously assumed. Rather than being filled with swarms of 10 km diameter planetesimals accreting directly into the four inner planets, it was realized that accreting matter would form embryonic planets with a large range of sizes in closely spaced orbits. The final stages of planetary formation would involve the coalescence of often rather large bodies, punctuating this era with giant impacts in which bodies of comparable size crashed into one another at high speed. The chaos of this era explains the wide variations in orbital inclinations, eccentricities, rotational periods and spin axis directions observed among the inner planets at present.A giant impact provides just the right circumstances for a body with the moon's peculiar chemical composition to arise. The vapor squirted from the contact point between the proto-earth and the impacting smaller protoplanet would consist predominantly of material from the mantles of the two objects and should exclude core metal. Condensing in space, the high-speed cloud of rock vapor would preferentially incorporate refractory elements, while volatile elements would be slow to condense and hence may be greatly depleted. The large amount of angular momentum brought in by the projectile would mostly go into the orbiting debris, although the proto-earth would also be spun up. From the angular momentum of the present earth-moon system the projectile must have had a mass comparable to that of the planet Mars.

kiki070300123 · 发表于 2011-11-19 20:32:24

寂静12的有关so4作为气体溶剂减缓全球变暖的资料
Aerosols can cool the climate in two basic ways: either directly, under clear sky conditions, by reflecting away some of the incoming solar radiation, or indirectly, by increasing the reflectivity of clouds.

During the late 1960s, in the process of trying to measure and understand the optical clarity of the atmosphere, Charlson realized that existing instrumentation for measuring aerosols was inadequate. The old measurements were done by eye and were only approximate. So he designed and built a new device, patented by the University, to analyze the light-scattering power of atmospheric aerosols. The technology currently forms the basis of the Model 3550/3560 Integrating Nephelometer marketed by a Minnesota-based company called TSI Incorporated. The nephelometer made it possible for the first time to quantitatively assess the amount of sunlight reflected back into space by sulfate aerosols.

Charlson's original work on the role of aerosols in the global heat balance, published in 1969, did not attract much attention, nor did a subsequent paper on sulfate in 1976. It wasn't until the global warming debate heated up, so to speak, in the late 1980s and early 90s that the importance of his work began to be fully appreciated.

Charlson and colleagues have shown that the cooling effect of sulfate aerosols does not neatly cancel out the effects of greenhouse warming, but rather, makes the situation more complex. "Aerosol cooling and the greenhouse effect have characteristics that prevent them from neatly offsetting each other," note Charlson and colleague Tom Wigley, who heads the Office for Interdisciplinary Earth Studies at the University Corporation for Atmospheric Research in Boulder, Colorado.

First, the cooling and warming occur mostly over different parts of the world: the aerosol effect is focused over industrial areas in the Northern Hemisphere, whereas warming effects may be greatest over subtropical oceans and deserts. There are also temporal variations. Aerosol effects are most pronounced during daylight hours during the summer season; the activity of greenhouse gases differs very little over the course of a day, or over a year.

The work of Charlson and colleagues suggests that forcing by sulfate aerosol is not evenly distributed over the globe--it can vary by roughly a factor of five from region to region. As a result, the world might expect to see dramatic changes in regional weather patterns in the future, not just an increase in average global temperature.

Furthermore, Charlson's work demonstrates how to incorporate particular chemical and physical measurements made on the local scale into models of atmospheric dynamics on a global scale. For that achievement, Charlson was awarded an honorary doctoral degree from Stockholm University in 1993. Sulfate aerosol was named by the journal Science as one of nine runners-up for Molecule of the Year in 1995.

kiki070300123 · 发表于 2011-11-19 21:01:53

另外我估计寂静里面有个白天黑夜的温度不同的原因的答案是
interaction
我觉得工厂peaktime那个答案很牵强，有一篇论文就是讲因为longwave的吸收率不同导致的interaction不同
所以大家参考一下

kiki070300123 · 发表于 2011-11-19 21:03:33

http://www.pnas.org/content/103/12/4371.full
论文地址

spr · 发表于 2011-11-19 22:49:16

richardlrui · 发表于 2011-11-19 22:53:07

关于地月的yd，我发现一个非常接近于大家的寂静的英文文章

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