Natural Disasters: Earthquakes

The earth has been acting quite violently lately: earthquakes in China, Iran and the Midwest, volcano in Chile, cyclone in Myanmar and other stuff. My question: is the earth behaving normally or are these disasters coming more and more frequently? In the next few weeks, I'll be researching some common natural disasters to see if there's been a spike in activity or if it's just Mother Nature's regular routine of doom.


Are there more now than before?
As far as earthquakes go, it seems that there is a steady increase of quakes each year since 2000 (see TABLES.) There's a few good TABLES and GRAPHS at USGS' website, plus a boatload of information on quakes. I have a very strong sense that a lot of the information is skewed. I base this on the fact that earthquake detection methods and technology is improved and captures more events. Another reason that the numbers are skewed: humans' incessant breeding. Then, when we're done breeding, we go find a crowded, condensed city to live in. When Mother Nature gets the taste for blood, she's got some easy, centralized targets to work with.

Can we predict them yet?
Although the obvious answer is no, I wanted to know if there's any way to predict earthquakes or if we're getting closer to something like that. NPR has good material at "Seismologist Says Aftershocks Impossible to Predict."

I found that there was a 2005 article in Wired talking about new technologies that don't claim to predict earthquakes used by themselves, but they are certainly a step in the right direction. One of the new techniques actually predicted that something was brewing 4 months before the huge 2004 tsunami. Check out the whole article at "Quake Prediction Gets Shake-Up."

Then I found this Reuters article called "Japanese gadget can predict tremors before they hit." This was published in June 2007 and my first thought was: "You didn't think it'd be a good idea to share this with the rest of the world?" The device is said to not be completely accurate, but it does give a 20-second warning.

Can animals predict earthquakes?
Twenty seconds could be enough to get you moving toward safety, but do you really need a gadget? How about a pet? Or a panda? The idea that animals can predict earthquakes is not founded in science, but rather passed along over centuries through anecdotes.

Panda Video from National Geographic: http://news.nationalgeographic.com/news/2008/05/080515-tourists-video-ap.html

What's the current situation in China?
In a word: bad. There are dams, both natural and man-made that are giving way. Look at this satellite photograph of how the earthquake has caused a lake to form. And as if it couldn't get any worse, in the Anhui provice to the east about 24,000 people are infected with this child virus. The virus hasn't done nearly the damage that the quake has, but it just seems like when it rains it pours in China right now.

Here's additional quake facts from the Chinese Information office:

  • The death toll has climbed over 68,000 people.
  • Another 364,552 people were injured and 19,851 others were still listed as missing following the 8.0-magnitude quake that hit Sichuan Province.
  • A total of 243 aftershocks were monitored in the quake zones during the 24 hours ended at Wednesday noon, according to the China Seismological Bureau.
  • By Wednesday noon, 8,911 aftershocks had been detected in the quake-hit areas since May 12, according to the bureau.
  • These aren't little tremors. They have ranged on the seismic scale from 3-6 points.

Here's a list of the worst 10 known earthquakes (issue date wasDecember 31, 2004, so 2004 numbers are not latest):

  1. Shanxi, China, January 23, 1556: magnitude 8 (estimated); 830,000 deaths
  2. Tangshan, China, July 27, 1976: magnitude 7.5; 255,000 deaths (official toll; actual deaths estimated up to 655,000)
  3. Aleppo, Syria; August 9, 1138: 230,000 deaths
  4. Near Xining, China, May 22, 1927: magnitude 7.9, 200,000 deaths
  5. Damghan, Iran, December 22, 856: 200,000 deaths
  6. Gansu, China, December 16, 1920: magnitude 8.6; 200,000 deaths
  7. Ardabil, Iran, March 23, 893: 150,000 deaths
  8. Kanto, Japan, September 1, 1923: magnitude 7.9; 143,000 deaths
  9. Off coast of Sumatra, Indonesia, December 26, 2004: magnitude 9.0; at least 140,000 deaths
  10. Ashgabat, Turkmenistan, October 5, 1948: magnitude 7.3; 110,000 deaths

Source: "Accidents and Disasters: Ten Deadliest Earthquakes." Facts On File World News Digest 31 Dec. 2004. Facts On File World News Digest. Facts On File News Services. 28 May2008 http://www.2facts.com.

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