|What is the difference between a hurricane and a
tsunami? Which one is more severe?
|Question Date: 2005-01-11|
A hurricane is a large storm system that
the atmosphere over warm ocean water. A tsunami
is large set of waves triggered by some sort of
vertical movement of rocks under water
(earthquake, large landslide, volcanic
explosion). Both of them can be very severe when it
comes to impacting humans, but overall hurricanes
have probably caused more damage and deaths. We
have seen in the last month (today is January
11th, 2005) that a large tsunami
can kill more than 150,000 people and do untold
damage, but hurricanes are a lot more common and
have killed about 600,000 people in the last 50
years (most of them in low-lying Bangladesh).
Hurricanes have very strong winds spinning around
the center of the storm. These winds push up a
mound of water called a "storm surge". In the
most intense hurricanes, this storm surge can be
7-8 m high (~25 ft). It does not arrive nearly as
quickly as tsunami waves, but it can stay for many
hours and along with >100 mile/hr winds and lots
of rain, it can cause a lot of damage. However,
the best defense against both hurricanes and
tsunamis is early warning systems (easier for
hurricanes) and leaving coastal areas when
instructed by authorities (or in the case of a
tsunami - as soon as the earth stops shaking,
leave the beach!).
A hurricane is a storm in the atmosphere; a
tsunami is a huge tidal wave in the ocean, caused
by a large under thrusting earthquake. They are
entirely different phenomena. Both have the
potential to be very damaging. The thing about a
tsunami that makes it worse is that, as happened
in Indonesia, there is little advance warning
without the proper detectors installed at sea, so
the people could not escape. You usually have
enough time to get out of the way of a hurricane,
and get to shelter. The force of so much water is
greater than that of a hurricane, but hurricanes
also last longer and so can cause lots of damage
also. I have never heard of a hundred thousand
people dying from one hurricane,
though. But - don't worry. We have a good
tsunami warning system in California, in case
there is any great earthquake in Alaska that
causes a tsunami in our side of the Pacific Ocean,
so we can get out of the way. They did not have
this in Indonesia and India - and you know all
about the damage, from the news reports.
They are not the same thing at all.
hurricane is essentially a gigantic thunderstorm
that swirls in huge regions of cloud, with
colossal winds, very low atmospheric pressure (for
sea level), and torrential rain.
is a pressure wave generated by a change in the
shape of the sea-floor, particularly by a change
in the depth of the sea-floor (itself by an
You can make a little tiny
tsunami in a bathtub. When you insert your body
into the bathwater, you generate a pressure wave.
If you go deeper, so that more of you is
submerged, you generate a pressure wave.
Obviously, if the area being submerged is the size
of the state of California and is moving several
meters (the recent earthquake off Sumatra), the
displacement of water is going to be huge, and the
tsunami will be similarly huge. Hurricanes, by
the nature of air flow, have to be big. Every
few years, a typhoon (another word for hurricane,
just one that hits Asia) slams into Bangladesh, a
lowland country. The entire country is flooded,
and it kills well over a hundred thousand people.
The recent tsunami in the Indian Ocean killed a
Click Here to return to the search form.
Copyright © 2017 The Regents of the University of California,
All Rights Reserved.