Welcome to 'wild weather central'

Wind rushes over the top of Mt. Washington the way water cascades down mountain rivers - nothing stands in its way. The wind batters the mountain, whisking loose objects off into steep ravines that encircle its bulk.

Hail, sleet, rain, and snow pummel the peak in every season. The summit is foggy 300 days of the year. All this makes the White Mountain peak in New Hampshire one of the best places on Earth to study extreme weather.

"This place has severe weather you don't find anywhere else," says Eric Pinder, a five-year veteran of Mt. Washington's weather observatory. "We're just a couple of hours' drive from Boston, but overall our weather is more severe here than at the South Pole."

At 6,288 feet above sea level, the mountain hardly rates a yawn compared with the 14,000-footers in the Rocky Mountains or 29,000-foot Himalayan peaks. But because of where Mt. Washington is, weather is funneled over the peak from the Great Lakes and the Atlantic coast. The mountain is in the path of the jet stream, a powerful, fast-moving current of air that snakes around the world. As a result, Mt. Washington gets some of the worst weather on the planet. No wonder every building, bench, and tower is anchored with wire cables and thick chains. It's because of the wind.

You can't see wind, but you can see what it's doing - moving dust, fluttering leaves. Sometimes you can taste the wind, when it carries the salty scent of the sea or the sweet scent of newly cut hay. Mostly, though, wind is something we feel, like waves from an invisible ocean washing over us.

It's important, too. "Wind is critical to human existence," says Chris Bedford, chief meteorologist for Sailing Weather Services, a global weather-forecasting company based in Watertown, Mass. Wind moves weather patterns, makes waves on lakes and oceans. "Without wind," Mr. Bedford notes, "there's no rain. It's as life-giving as water."

Wind begins with sunshine

The sun is the source of wind, because it heats the earth unevenly. Sunlight falls directly on the equator, for example. The North Pole receives weaker, slanted rays of sunlight. Clouds may keep one area cool while another heats up. Water and land heat up at different rates. Hot air is lighter than cool air, so it rises. As hot air rises, cool air slides in to replace it. The result: wind.

The movement of air - wind - creates complex patterns. For example, meteorologists (scientists who study weather) know that a change in the wind in Seattle will affect the weather in New York two days later. If scientists could "read" the winds' patterns better, they might be able to forecast the weather better.

But - remember? - you can't see the wind, so you can't photograph it from space. Or can you? Researchers here are looking into this.

The wind has drawn observers to the top of Mt. Washington since 1932, when the weather observatory opened. Finding a good, steady wind to study here is usually just a matter of showing up for work. It was here that a world-record ground-wind speed was recorded: 231 miles per hour on April 12, 1934.

Four thousand feet below the summit, in a small modular building at the end of an unmarked, unpaved road, things are much quieter. Here, researchers of the Groundwinds project are developing an instrument to better "see" the wind with a high-powered laser. It's a called LIDAR, for "light detection and ranging." It's laser radar.

"This is a technological breakthrough," says Lynn Rosentrater, a researcher at the University of New Hampshire in Durham. "But what makes it truly unique is its potential to measure global winds."

1,800 weather balloons a day

Today's meteorologists depend on weather balloons to determine wind direction. At 900 sites around the world (mostly in the middle latitudes), weather balloons are sent up twice a day. Instruments determine wind speed and direction. If it works, the Groundwinds LIDAR could be put on satellites. Scientists could take a laser "snapshot" of the Earth's winds from orbit.

In the New Hampshire night, the Groundwinds laser looks more like a Star Wars light saber than a science tool. Scientists shoot the bright-green laser into the sky above Mt. Washington. The laser beam hits moving molecules of air. By measuring how the laser light is scattered when it hits air molecules and dust, scientists can figure out how fast the wind is blowing, and in what direction. Similar instruments are already in use. But they only bounce a laser beam off the tiny particles being carried by the wind, such as dust or drops of water. The Groundwinds laser uses the air molecules in the wind itself.

If the Groundwinds laser works, it should greatly improve weather forecasts. "The ability to predict extreme weather will increase substantially," Ms. Rosentrater says. "It will have a huge impact on public safety and our ability to forecast hurricane landings."

For now, though, scientists at Mt. Washington continue to collect weather data and observe. "Anything can happen at any time," says weather observer Brian Post with a twinkle in his eye. "You are on a mountain that is in the running for the worst weather in the world."

*For more mountaintop images, go to: www.csmonitor.com/wind.html

(c) Copyright 2000. The Christian Science Publishing Society