today
9 a.m. Doris Niles Humboldt County Science Fair Humboldt State University
read >10 a.m. Annual Juggling Festival Humboldt State University
read >10:30 a.m. Green Jobs Fair College of the Redwoods Downtown Site
read >11 a.m. Baby Read and Grow Program Humboldt County Library
read >1 p.m. Apple Solutions for Small Business See Event Description
read >4 p.m. Young Parent Support Group College of the Redwoods Kinship Site
read >6 p.m. The Tumbleweeds (cowboy songs) Chapala Cafe
read >6 p.m. Bon Swing Libation
read >6 p.m. Annual Pisces Party See Event Description
read >6 p.m. Annual Pisces Party See Event Description
read >7 p.m. DJ Ray Boiler Room
read >7:30 p.m. Arianna String Quartet Calvary Lutheran Church
read >7:30 p.m. A Midsummer Night's Dream Arcata High School
read >8 p.m. Eureka Symphony Concert Arkley Center for the Performing Arts
read >8 p.m. Humboldt Folkdancers Arcata Presbyterian Church
read >8 p.m. On the Wings of a Dove Carlo Theater (Dell'Arte)
read >8 p.m. Antigone College of the Redwoods
read >8 p.m. So Hum Tales Mateel Community Center
read >8 p.m. Gentle Thunder Arcata Playhouse
read >8:30 p.m. The Last Minute Men (international) Cafe Mokka
read >9 p.m. Taxi (rock & roll) Bear River Casino
read >9 p.m. Vintage Soul (R&B) Cher-Ae-Heights Casino
read >9 p.m. Bump Foundation Pearl Lounge
read >9 p.m. The Brothers Comatose (folk) Six Rivers Brewery
read >9 p.m. The Malone (rock Red Fox Tavern
read >10 p.m. Music by DJ Sidelines
read >10 p.m. DJ Ninja Retro Dance Party Aunty Mo's Lounge
read >previous columns
March 13, 2008
In Formation
The V-formations of honking Aleutian Cackling Geese that decorate our ...
read >March 6, 2008
The Ins and Outs of Tides
The Moon's gravity decreases with distance, so it pulls unequally ...
read >Photos
Tsunami Terrors
By Don Garlick
Understanding the nature of tsunamis could save your life. They are usually caused by large earthquakes, coastal or submarine. You could expect timely warning of a tsunami generated thousands of miles away, but if our local Cascadia Megathrust is the culprit, the violent shaking would be your cue to head for the highest ground reachable within a few minutes.
Tsunami waves have wavelengths of a few hundred kilometers and travel at almost 800 km per hour in deep water. The first image shows a simulation, by the USGS, of waves 4 hours after their creation by the Magnitude 9 Cascadia quake of Jan 26, 1700, dated by Japanese records. The map shows the propagation of such a tsunami at hourly intervals. It would reach Hawaii in five hours. One generated in Hawaii would reach us in five hours.
The plot of wave height verses water depth explains how a wave may be imperceptible at sea but damaging on the coast. Additionally, long-wavelength waves are more likely to surge than to break. A tide gage at Sitka, 1,000 km from the 1964 Alaskan epicenter, reveals the long duration of tsunami waves.
On March 26, at about 10:30 a.m., there will be a test of NOAA's Tsunami Warning System. Visit www.wrh.noaa.gov/eka/misc/tsunamitest.php for more information.
I thank Prof. Lori Dengler for her input.






















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