Earth Hour 2011

Earth hour is a global movement to encourage people, individuals, businesses and governments around the world to show their commitment and their engagement in taking positive actions for the environment by turning off the lights. It takes place the 26th of March, between 8.30 and 9.30 pm local time (link to earthhour website).

Tsunamis

A tsunami can be triggered by for example an earthquake, volcanic eruption or landslide. Around 80% of all tsunamis are caused by earthquakes. The tsunami is triggered when the seafloor is abruptly deformed and the water above it is vertically displaced. A wave with a low wave height (around half a meter) and long wavelength (more than 10 km) is created and travels over the sea. When the wave reaches the shore, it compresses and transfers to a high wave with short wave length (read more).

And for all my surfer crazy friends, from the GNS Science GNS Science website:

"Is a tsunami a dream come true for extreme surfers?
No. A tsunami is not a wave in the classical sense, but a raging torrent of water that surges inland with enormous power - much more power than a surfer can handle. Besides the waves do not stop at the shore, so surfers may find that they crash into buildings or all the other debris caught up in the surging water. Invariably a tsunami consists of successive surges or torrents and equally violent return flow to the sea. The first wave or torrent of a tsunami is not necessarily the biggest. The second or third or even much later waves may be bigger. Intervals between successive waves can vary. It may just be minutes, or it could be more than an hour."

Earthquakes in the Japan and Tokyo region

Mother nature showed once again who really is the head of the earth. Japan is used to and prepared for earthquakes (see list of major earthquakes in Japan) but who can be prepared for an earthquake of magnitude 9.0 and a tsunami triggered by it? According to the news I heard on radio a couple of days ago, three tsunamis of the size of the 11th of March tsunami in Japan, has occurred the last 3000 years.

About 300 km from Tokyo is an underwater so called triple junction, where three tectonic plates meet (Toda et al.). Scientists believe that a fragment of the Pacific tectonic plate is jammed between the Pacific, the Philippine and the Eurasian tectonic plates (Toda et al.), and that the probability for a major earthquake within 30 years in the region is 30 % (Stein et al.). After the 11th of March earthquake this probability might have to be reconsidered (read more), and some scientists fear more large aftershocks, or even a "mega quake" in the region (read more).