Page 3 - Microsoft Word - 12.3 TSUNAMI AND CYCLONE

Where do tsunamis occur?

Tsunamis can occur in any major body of water. They are most common in the Pacific Ocean where
there are lots of underwater earthquakes and volcanoes.

Largest tsunami recorded
An earthquake followed by a landslide in 1958 in Alaska's Lituya Bay generated a wave 100 feet high,
the tallest tsunami ever documented. When the wave ran ashore, it snapped trees 1,700 feet upslope.
Five deaths were recorded, but property damage was minimal because there were few cities or towns
nearby.

CYCLONE

What is a cyclone?
A cyclone is a general term for a weather system in which winds rotate inwardly to an area of low
atmospheric pressure. For large weather systems, the circulation pattern is in a counter clockwise
direction in the Northern Hemisphere and a clockwise direction in the Southern Hemisphere.

What causes cyclone?
Cyclones are centred on areas of low atmospheric pressure, usually over warm ocean waters near the
equator. The warm moist air over the ocean rises from the surface in the upward direction, resulting in
the formation of the low-pressure zone over the surface.