Dam the Sky

Scott LaFee
Thu, 07 Jan 2010 00:00:00 -0800
Lifestyle

Dams do a heckuva job of controlling river flooding, but at a possible cost from on high: Bigger and more extreme storms.

Researchers at Tennessee Technological University analyzed weather patterns before and after construction of 633 of the largest dams in the world. They found that at many of these dams the level of rainfall in the most extreme storms grew by an average of 4 percent per year after the dams were built, with the connection strongest in semiarid regions.

The research is the first to show a clear relationship between weather, rainfall and climatological effects created by large bodies of water formed by dams. The results were not consistent across the board, but scientists say that's due to regional weather patterns and other localized factors.
Updated: Wed Jan 06, 2010

Dams do a heckuva job of controlling river flooding, but at a possible cost from on high: Bigger and more extreme storms.

Researchers at Tennessee Technological University analyzed weather patterns before and after construction of 633 of the largest dams in the world. They found that at many of these dams the level of rainfall in the most extreme storms grew by an average of 4 percent per year after the dams were built, with the connection strongest in semiarid regions.

The research is the first to show a clear relationship between weather, rainfall and climatological effects created by large bodies of water formed by dams. The results were not consistent across the board, but scientists say that's due to regional weather patterns and other localized factors.

NUTS FOR HOME

Already deemed smarter than the average invertebrate, octopuses have now been observed lugging around coconut shells to use as portable shelters, the first example of reported tool use by an animal lacking a backbone.

According to New Scientist magazine, the octopuses move the shells by draping their bodies over half shells, hollow side up, with their eight arms dangling over the edges. Then, they make their arms rigid, which lifts the coconut shell, after which they "tiptoe" away. It's not clear how octopuses acquired this trick, whether from observation or imagination.

Julian Finn of the Museum Victoria in Melbourne, Australia, who has filmed four veined octopuses moving coconuts, said the behavior qualifies as tool use because the octopuses do not use the shells as permanent homes (like hermit crabs) but rather as occasional hangouts.

PRIME NUMBERS

1,000 (plus) — Average number of people hospitalized each year with aviation-related injuries in the United States

10.6 — Percentage of those hospitalized who were traveling in commercial aircraft

32 — Percentage traveling in private planes

Source: Johns Hopkins University

VERBATIM

Maybe you shouldn't be doing it in the first place.

— Eric Schmidt, Google's chief executive, reminding Internet users that search engines (including Google) regularly expose online activities or information that people might prefer to remain secret

THE GEEK ATLAS

Chateau du Clos Luce

Amboise, France

47 degrees 24 minutes 36 seconds N, 0 degrees 59 minutes 29 seconds E

Leonardo da Vinci's (1452-1519) final three years of life were spent here in a chateau furnished by King Francis I. The chateau, restored to its Renaissance state, contains da Vinci's bedroom, workroom, a museum containing many of his most unusual inventions, and gardens that illustrate his ideas and art. There's even an underground passage leading to another chateau once owned by Francis. Reportedly, the king used it when he wanted to surreptitiously visit da Vinci.

WHAT IS IT? ANSWER

A full-sized model of Leonardo da Vinci's design for a battle tank. It can be seen at the da Vinci museum at Chateau du Los Luce in Amboise, France. The turtle-shaped vehicle, ringed with cannon, would have been powered either by horses or by men turning cranks to power wheels.

Da Vinci favored the second option because he thought horses would be difficult to keep calm, particularly inside a noisy tank. No actual vehicles were ever built. The first working tanks debuted 400 years later during World War I.