31 Aug '13, 10pm

The Virtues of Pure Snow: Scientist Tom Painter examines the differences between pure and dirty snow. A rise i...

At least as far back as King David’s psalms and Isaiah’s prophecies, snow has been characterized as a symbol of purity. “Lawn [linen] as white as driven snow” was how Shakespeare once described it. Beyond the symbolism, the purity of snow has consequences for society. Snow is a key source of water for drinking and irrigation. It is also Earth’s best method for reflecting sunlight back into space. Tom Painter is very interested in the purity of snow. Based at NASA’s Jet Propulsion Laboratory and the University of California, Los Angeles, he studies how much water is stored in snowpack and how that snow looks to satellites. He also studies the effects of light-absorbing impurities—dark-colored particles like dust and soot that coat snow. Dirty snow usually melts faster than fresh snow because it absorbs more energy from the Sun, and that’s not just a problem in sooty, gritty...

Full article: http://earthobservatory.nasa.gov/IOTD/view.php?id=81959&s...

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The Virtues of Pure Snow: Scientist Tom Painter...

earthobservatory.nasa.gov 31 Aug '13, 10pm

At least as far back as King David’s psalms and Isaiah’s prophecies, snow has been characterized as a symbol of purity. “L...

The Virtues of Pure Snow [image] #NASA

earthobservatory.nasa.gov 01 Sep '13, 2pm

At least as far back as King David’s psalms and Isaiah’s prophecies, snow has been characterized as a symbol of purity. “L...

JUJUBE RECIPE

JUJUBE RECIPE

noobcook.com 31 Aug '13, 5pm

(tong shui) to make at home. It is often cooked during Chinese New Year and auspicious occasions (I remember having it at ...