A relatively calm area in the center of the storm.
the eye
Smaller quakes produced after a major quake that are caused by rocks shifting to new positions.
aftershocks
A tornado that forms over water.
a waterspout
Regions in these zones often have warning systems in place to give people as much time to evacuate as possible.
tsunami danger zones
Hot liquid rock under the Earth’s surface is known this; it is called lava after it comes out of a volcano.
magma
The maximum sustained surface wind of a hurricane is at least this speed or greater.
74 mph
Waves of energy that are released during an earthquake.
seismic waves
This swirling cloud is the first sign of potential tornadic activity.
a funnel-shaped cloud
Tsunamis are huge waves of water that are usually caused by earthquakes or these.
volcanic eruptions
Sulfur dioxide is shot into the atmosphere by a volcano, then mixes with rain and falls back to Earth as this.
Acid Rain
An organized ring of cumulonimbus clouds that surround the eye.
the eye wall
The underground point of origin of an earthquake where the rocks break and move.
the focus
This country averages around 1200 tornadoes every year, more than any other country.
the USA
When tsunamis hit shallow water (often near the coast) they slow down but increase in this.
height
A giant flat volcano with a giant magma chamber that can eject thousands of cubic km of ash, rock and lava with an eruption 10 000 times stronger than any eruption in recent history.
a supervolcano
An abnormal rise of water generated by a storm.
a storm surge
The instrument used to measure the strength or magnitude of an earthquake.
the Richter Scale
The majority of US tornadoes occur in a geographically unique area nicknamed this.
‘Tornado Alley’
In March 2011, the Tohoku earthquake off the eastern coast of this country caused a tsunami that was a major factor in the death of over 15000 people.
Japan
The word volcano originally comes from the name of this Roman god of fire.
Vulcan
A 1 to 5 categorization based on the hurricane's intensity at the indicated time.
the Saffir-Simpson Hurricane Wind Scale
A huge crack that runs through most of California that separates the North American and Pacific plates.
the San Andreas Fault
Tornadoes are rated from EF0 - EF5 on this scale, developed in the 1960's and based on observed damage.
the Enhanced Fujita Scale
The Japanese word tsunami literally means this.
‘harbor wave’
A thick cloud of superheated gas and ash which, upon eruption, flows down the volcano at top speeds of 150mph, destroying everything it touches.
Pyroclastic Flow