Storm-Sheltered Shores
Aren't Safe from Tsunamis
By recreating the deadly effects of a giant tsunami, UW engineers have found that even localities sheltered from storm-driven waves can be wiped out by the earthquake-driven tsunamis.
"While it would be difficult to prepare for such a disaster, our study suggests that no one who lives on an ocean island anywhere in the world is immune from the reach of a strong tsunami," warns UW Civil Engineering Professor Henry Yeh, who helped recreate a giant wave in an artificial wave basin.
Yeh and colleagues studied a 1992 wave that killed 263 people in the Flores Islands of Indonesia. That tsunami was more than 75 feet high in places and traveled 225 miles per hour.
Using a U.S. Army Corps of Engineers facility in Mississippi, the engineers found that villages on the far side of one island were devastated because the island cleaved the wave in two. When the two halves met again on the leeward side of the island, the waves collided. The impact was worse than on the side of the island first hit by the wave, Yeh explained.
The experiment puts to rest the myth that coastal island settlements naturally protected from normal winds--or even hurricanes or typhoons--would be equally safe from the reach of a tsunami.
Reviewing sociological data from the last 30 years, Burstein notes that women have realized the biggest increases in earnings; more women were pulled into the labor force than any other group with more kinds of jobs opening up to women; and the American concept of discrimination has changed in ways that benefit women.
The benefits for women apply to both white and black women, Burstein adds. "Black women's earnings don't suffer much from racial discrimination, they suffer from gender discrimination on the job," he explains. "This is not to say, however, that some black women are not treated badly when they go to work."
Black men have benefited from the landmark legislation, but "not in the dramatic way some people have wanted, and they haven't benefited much recently," Burstein reports. He says that there is some recent data that suggests opportunities for well-educated black men are improving, but that not all sociologists agree with these studies. There is little data available that measures the impact of equal employment opportunity provisions on various national-origin minorities, such as Hispanics, he adds.
Which is better for managing a watershed: young trees or old growth forests?
There is some evidence that young trees use less moisture because of their size. At the same time, other research indicates that old-growth forests retain more water in the landscape. Old-growth forests on ridges and hilltops are tall enough to be brushed by low-elevation clouds, and the foliage can be so saturated that water drips down though no rain has fallen.
To help resolve the debate, UW forest resources professors and students have built probably the largest research tower for studying tree canopies in the United States--a 135-foot tower in the Cedar River watershed of the central Cascade Mountains.
Made out of a ton and a half of metal that had to be carried--by hand--a mile to the research site, the tower enables researchers to take readings from the ground to the treetops. The results may help cities that rely on surface water better conserve the resource. During the year, 40 percent or more of the rain and snow that falls in a typical watershed doesn't end up in the waterways, says Forest Resources Professor Tom Hinckley.
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