DO SOME ANIMALS FEAR HEIGHTS?
Most animals have a natural respect
for heights, and young birds are
known to be particularly careful.
Black-legged kittiwake babies, which
grow up on narrow rock ledges by
the coast, spend most of their
childhood with their backs
to the ocean, looking at the
rock wall, so they do not see the
drop they must face, when
they first take flight.TERRY WHITTAKER/REX/ALL OVERCan We Build A Tsunami
Warning System?
Where is the risk of being struck by a tsunami most significant,
and is it possible to warn people on the shores, before it strikes?Tsunamis can be triggered by
landslides or volcanic eruptions, but
the major tsunamis which might
strike multiple coasts are most often
triggered by earthquakes.
Before a tsunami can form, a
severe vertical motion must move
the water column up or down,
triggering a wave. The major South
East Asian tsunami disaster in 2004
was triggered when the Indo-Australian Plate dived into the
Sunda Trench. Major quakes of the
vertical type occur when two
tectonic plates collide – such as all
the way around the Pacific Ocean,
where the risk of a tsunami is the
most significant.
A network of buoys and other
sensors monitor waves throughout
the Pacific Ocean, transmitting data
to the Pacific Tsunami Warning Centre(PTWC) in Hawaii, which operates
24/7. The PTWC can issue a warning
to the nations around the Pacific
Ocean. The countries either sound the
alarm automatically or assess the
warning before initiating evacuation.
In other places, tsunami
warnings are local. That is the case
near Mount Åknes in Norway, which
threatens to slide into the Geiranger
Fjord, causing a 70-m-high wave.PACIFIC IS MOST AT RISK
All the way around the Pacific Ocean,
continental plates push underneath
each other. Powerful vertical motions in
Earth's crust might cause earthquakes
and tsunamis topping five metres high,
when they hit the coast.5+ M WAVES
2+ M WAVES
LESS THAN 2 M WAVESTSUNAMI RISKAsk Us
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