Steve's blog

Earlier we learned half of the Acqua Alta story in terms of favorable tides. The second half of the lesson involves resonance.

Thumbnail Tutorial Continued:

(2) Resonance: I discussed resonance previously here under the title “Seismic Slosh”...

http://www.openhazards.com/blogs/steve/seismic-slosh-swimming-pools-and-...

In that example, the resonance was in reservoirs and the cause was seismic shaking. 

 Have you ever visited Venice Italy? From a geophysical perspective (Is there any other?), Venice has a curious attribute. Certain times of the year the city endures Acqua Alta – high water- when the sea rises up and floods the lowest areas of town. City workers dutifully unpack and set up wooden walkways so folks can get about the place without wet feet. Cafe owners construct temporary platforms in front of their shops tempting tourists to partake coffee and biscotti whilst high and dry. In a few days the flood

Not likely that you’ve ever thought much about Gulf of Mexico tsunami. Seeing that most tsunami birth from large earthquakes, and that the Gulf hosts only smallish ones, your lack of concern is justified. Still, things other than quakes cause tsunami -- submarine landslides for one.

Have you read about that meteor that blew up over Russia a few days ago? Amazing. A rock from space hasn’t caused serious damage and human injury since  --- I don’t know -- the days of Christopher Columbus. True, a similar but bigger meteor exploded over Siberia in 1908, but that area was virtually uninhabited.

If you’ve been reading John’s blog, you know that he is forecasting a large earthquake near Japan “sometime soon”. 

Have you heard of the term ‘card counting’?  Strategists employ the technique to predict the outcome of the casino game “21”. Well, John is basically ‘quake counting’.

All around the world, earthquake statistics follow a fairly universal pattern. 

(A) If in a given region over a given period of time you have experienced a certain number of magnitude 5 quakes,  then you’d expect one of magnitude 6.

I read that Hurricane Sandy inflicted 50 billion dollars of property damage. I don’t know what fraction of the 50 billion was purely wind-sourced versus the fraction caused by storm surge. Certainly, the most graphic pictures of the damage in my mind are the homes tossed helter-skelter by the latter. A close second are images of businesses and houses sitting 6 or 8 feet deep in muddy water.

Many of my blogs involve natural disasters either hypothetical or long past. In a workaday world, it’s understandable for one to be blasé about such things. Sure, ‘what if’ events are possible, but why care?

To counterbalance this tendency, I like to highlight cases where

                                ‘What if’   became   ‘Just did’

When I went to school, back in the Paleocene, students memorized a list of phrases spoken by famous Americans.

                  “Don’t give up the ship.”

                       “I shall return.”

If you live in California and conversation drifts to earthquakes, the “BIG ONE” always surfaces.

 ‘Hey Steve, when’s the next BIG ONE coming?’

For out-of-towners, a BIG ONE refers to a ~M8 earthquake on the San Andreas Fault. The last BIG ONE was the 1906 San Francisco earthquake. Everyone knows that. The BIG ONE before that was the 1857 Ft. Tejon earthquake in the southern part of the State. Virtually nobody knows that. No surprise, in 1857 Los Angeles was a dusty backwater, home to about 4,000 townsfolk.

Rocks from space.  Most of us have stepped out into the backyard and looked up at the night sky to witness a wonderful, but brief, streak of light from a falling star. Hardly star size, those streaks originate from space bits as big as grains of sand. Larger things happen however. About once per year, a Volkswagen-size rock crosses Earth’s path. These zip from horizon to horizon, burning bright for 10 or 20 seconds --- long enough maybe, for someone with quick hand on a camcorder to catch the show for appearance on the evening news.