SNOWFALL: ANOTHER THEORY COLLIDES WITH REALITY

Big scare! Pollution is reducing snowfall so the rivers might run dry! Problem: Pollution also increases rainfall. Bigger problem: The historical record does not show any big reduction in meltwater over time. Lesson: Studying just one effect in isolation should be left to the scientists. Drawing big conclusions from just one change is dumb

"Along the western slope of the Rockies, in a laboratory 10,500 feet above sea level, a team of atmospheric researchers has spent the past decade deciphering a deeper meaning from the blizzards that blanket the Steamboat ski resort in its famously pillowy "champagne powder."

They have skimmed snow clouds with screens to size up their icy content. They have zapped falling flakes with lasers to record digital images of the hexagonal shapes. They have captured crystals in a contraption that melts them with a heat gun and measures the mass of the water droplets. And they have come to a provocative conclusion: Air pollution is reducing mountain snowfall, the wellspring of drinking water for Los Angeles, Las Vegas and much of the urban West.

Storm clouds packed with microscopic particles from diesel trucks, coal-burning power plants and cow manure produce far less snow than clouds comparatively free of pollution, the scientists from the University of Nevada's Desert Research Institute have determined.

J. Marshall Shepherd, a scientist with the National Aeronautics and Space Administration who studies global rain patterns, agreed that Rosenfeld and other scientists are showing that pollution can reduce precipitation in high altitudes.

But other studies, including research by Shepherd on thunderstorms downwind of Houston, suggest that some of the same factors can actually increase the intensity of rain in lower-lying areas, where clouds hold together longer before finally releasing torrential downpours.

Many human activities appear to be altering storm clouds, including the hotter air that emanates from dense urban centers, known as the heat island effect. It will probably take scientists decades to fully understand what is happening, and how water supplies in different parts of the country are being affected, Shepherd said.

"There is certainly convincing evidence that aerosols are having an effect on precipitation," he said, "but there are other factors, including the urban heat island effect, and we are not sure how it all works just yet."

Maurice Roos, California's chief hydrologist, said he is skeptical of the scientists' claims. Roos has reviewed historical records, and concluded that though the snowpack has clearly diminished over the last 40 years, the trend is more likely linked to a slight uptick in temperatures.

If air pollution was causing the serious effects Rosenfeld and others have suggested, the state should be losing far more water, Roos said. "I would not be surprised if there was some influence" from air pollution, said Roos, who has spent 47 years as a state water official. "But we, happily, do not see the major changes in stream runoff that these guys are predicting."

More here.

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Many people would like to be kind to others so Leftists exploit that with their nonsense about equality. Most people want a clean, green environment so Greenies exploit that by inventing all sorts of far-fetched threats to the environment. But for both, the real motive is to promote themselves as wiser and better than everyone else, truth regardless.

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