17 February 2011


WEATHER ANOMALIES. Those of us who live in northern regions may wonder, if global warming is a reality, why are we seeing so much snow and Arctic cold? It turns out that there is no contradiction. An NPR segment, Warming Planet Can Mean More Snow, explains that "The fact that the oceans are warmer now than they were, say, 30 years ago means that there's an average of about 4 percent more water vapor lurking around over the oceans .... Warmer water means more water vapor rises into the air, and what goes up must come down." Combined with dramatically altered ocean and air currents, the increase in global temperatures and water vapor levels translates to a greater likelihood of precipitation, some of it in places which have previously been more arid.

The segment continues, "There's something else fiddling with the weather this year -- a strong El Nino. That's the weather pattern that, every few years, raises itself up out of the Pacific Ocean and blows east to the Americas. It brings heavy rains and storms to California and the south and southeast. It also pushes high-altitude jet streams farther south, which bring cold air with them .... A storm is part of what scientists classify as weather. Weather is largely influenced by local conditions and changes from week to week. It's fickle, fraught with ups and downs. Climate is the long-term trend of atmospheric conditions across large regions, even the whole planet. Changes in climate are slow and measured in decades, not weeks."

As glaciers and the polar ice caps melt, global ocean currents are already shifting, further altering both local weather and long-term climate. Extreme weather (hurricanes, monsoon rains, winter blizzards, and drought) is already increasing, and expected to continue to do so. A second NPR segment, Researchers Link Extreme Rains to Global Warming, makes exactly this point. As Bette Davis famously quipped in 1950, "Fasten your seatbelts, boys, it's going to be a bumpy night."

SMART BUILDINGS. So how do we cope with uncertain weather? One way is by making our homes and workplaces much more adaptable to change. The Research Support Facility in Golden, CO, is doing just that. Kirk Johnson reports that the architecture incorporates both passive and active energy-saving design features ranging from a photovoltaic roof array to a window shading system (see image below), from "light-bending louvres that cast rays up into the interior office spaces, to the giant concrete maze in the sub-basement for holding and storing radiant heat."

Energy-saving, weather-resistant buildings don't have to be entirely high-tech. Thirty years ago i read about a man living in the mountains of Nevada who designed and built a home which was heated solely by a south-facing greenhouse whose heat was circulated through spaces which enveloped the home, top to sides to bottom. Heat was then stored in a gravel bed beneath the basement. The only mechanical component? A simple fan. Elegant in its simplicity, the home was so efficient that the owner ended up selling electricity back to the power company.

As climate change accelerates in unpredictable ways, it's likely that we will all be looking for ways to adapt -- in our homes, our cars, and our lifestyles.

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