The Weather Notebook: This Week

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Weather Frogs
Monday August 26, 2002
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Long before we had the Weather Channel to deliver the local forecast to our television sets 24 hours a day, people relied on clues from nature to tell them what the weather would be like. One clue came from an unlikely source known as the weather frog.

Hi, I'm Bryan Yeaton and you're listening to The Weather Notebook.

In Old World Europe, people often kept a small tree frog in a glass partially filled with water. Inside the glass was a miniature ladder upon which the frog could perch. According to folklore, the frog would climb up the ladder as pleasant weather approached-the higher the frog ascended, the better the weather. When gloomy weather was about to set in, the frog would descend down the ladder into the water.

Whether or not there was any scientific basis for the frog's maneuvers is subject to debate, but Europeans trusted their amphibian forecasters so much that in modern-day Germany, people still reserve a special name for a meteorologist or anyone with more than a passing interest in weather: they call them Wetterfrosch , which literally means "weather frog."

If you'd like your own "weather frog" to tell you what the weather will be like, you can download a free program for your computer's desktop that shows a little frog, named Froggy, sitting on a small ladder inside a glass-just like his real-world counterparts. Froggy will give you forecasts for over 700 cities worldwide and will even hop up and down his ladder as the forecast changes. Hmm... Frogs on the Weather Channel. It could happen.

Thanks today to writer Sean Potter. The Weather Notebook is a production of The Mount Washington Observatory and is supported generously by Subaru of America and The National Science Foundation. For more information on weather frogs go to our website at weathernotebook.org. Thanks to assistant producer, Doug Sanborn.

GCC Looking Back
Tuesday August 27, 2002
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Hi, I'm Bryan Yeaton and this is The Weather Notebook's weekly segment on global climate change. Where would you find the weather for every season over the last 100,000 years? The answer lies deep in the ice of the world's largest island, as our series producer, Margaret Landsman reports.

Greenland, where it snows every month of the year and the ice sheet is two miles thick. It's been a gold mine for climate researchers like Deb Meese.

DM: In Greenland were able to go to 110,000 years on a year by year basis to see what the climate has been like in the past.

Meese and her colleagues were in Greenland from 1989 to 1992 and for every ten meters they drilled down they collected a ten centimeter cylindrical sample of ice. Recently, Meese, who is a research physical scientist with the Army Corp of Engineers Cold Regions Laboratory, invited The Weather Notebook to see a sample.

DM: And this piece of ice is 63,000 years old. So, it fell during the last glacial period.

ML: Can you describe what that looks like?

DM: It's a cylinder that has essentially been cut in half and what you can actually see in there are crystals. And what you're looking at are, you can see light and dark layers...

Those light and dark layers represent different seasons of the year. Meese is able to then determine what constitutes a whole year and she can do that for 110,000 years. Meese's colleagues then look at other aspects of the cores and by year can see such things as temperature shifts and changes in concentrations of greenhouse gasses. Such information helps them look into the future more accurately.

DM: If we don't understand what's happened in the past there's no way we can plug this information into the climate models to predict what's going to happen.

Margaret Landsman produces our weekly series on global climate change. The series is supported by the New England Science Center Collaborative and the Roy A. Hunt Foundation.

Wednesday August 28, 2002
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Think of the Pacific Northwest, and images of dripping temperate rainforests and flocks of urban umbrellas emerge. However, in a few areas such as within the British Columbia capital of Victoria, annual rainfall is low, even semiarid, accumulating less than most major American cities.

Hi, I'm Bryan Yeaton and you're listening to The Weather Notebook. A large region of precipitation minimum, called the rainshadow, covers the sunken valley of the Strait of Georgia between the coastal and continental ranges of Washington and British Columbia. This rainshadow reaches from Victoria on Vancouver Island across several BC Gulf Islands and the Washington State islands of Orcas, San Juan and Whidbey.

When Pacific maritime air ascends to cross the formidable coastal mountains of Washington's Olympic Peninsula and southern Vancouver Island, it drops rain on the western slopes by the buckets. In the Olympic Mountains, totals can reach 200 inches annually. Further north on Vancouver Island as much as 250 inches may fall.

Much moisture is lost from the airmass in the crossing, however, and on the leeward side, the air descending into the Strait of Georgia basin warms through compression, and cloud droplets in the airstream evaporate. Thus, rain formation is inhibited, and often prevented, within the rainshadow region.

Clear skies may prevail all day around the basin's center while a few miles west, heavy rain showers fall.

As a result, in Victoria's southeastern corner, annual rainfall totals around 24 inches while about 20 miles west of downtown as much as 58 inches accumulates annually. On Whidbey Island, the total is only 18 inches. In comparison, just outside the rainshadow zone, Seattle receives 37 inches and Vancouver, British Columbia, 46 inches.

Thanks to contributing writer Keith Heidorn of Victoria, British Columbia. The Weather Notebook is a production of The Mount Washington Observatory and is supported generously by Subaru of America and The National Science Foundation. Thanks today to marketing manager, Melody Nester.