Know and Understand Natural Disasters
A natural disaster is when events such as
earthquakes, mudslides, floods or wildfires affect people. Despite our inability
to control these events, we can plan and prepare for them to minimize damage
when they do happen. Below are brief explanations of disasters that are common
in California. Follow the links to more information about a specific
An earthquake is a sudden shift or movement of the
plates in the earth’s crust. On the surface, this moves and shakes the ground
and can be very damaging to poorly built structures. The most powerful
earthquakes can destroy even the best built structures. They can also cause
other disasters, such as tsunamis and volcanic eruptions. Earthquakes occur
along fault lines and are unpredictable. California is highly prone to
earthquakes because of its many active fault lines.
A flood is a natural disaster caused by too much
rain or water in an area, and could be caused by many different conditions. In
California, floods are most often caused by prolonged rainfall from a storm.
Flooding is particularly dangerous because it often leads to landslides or
A wildfire is a natural disaster that starts in
forests, deserts with heavy brush or other vegetated areas. They can be a great
danger to people who live in or near such areas. Wildfires can be started by
lightning, extremely dry vegetation in warm climates, human carelessness or
intentionally. In the wilderness they can quickly burn thousands of square
miles. In metropolitan cities such as Los Angeles, they can burn entire
neighborhoods. Southern California is very prone to wildfires because of low
annual rainfall, warm summers and dry vegetation.
A landslide occurs when soil, rocks, trees, parts
of houses and other debris is swept downhill. Landslides can be cause by
earthquakes, rain or general instability of the land. Mudslides are a special
type of landslide, in which heavy rainfall causes loose soil on steep land to
collapse and slide down. Mudslides occur with some regularity in parts of
California after periods of heavy rain.
A tsunami is a series of waves that happens when
water in a lake or sea is quickly displaced on a large scale. Disturbances such
as earthquakes, volcanic eruptions, landslides or meteorite impacts can cause
tsunamis. Because the most common cause is an undersea earthquake, there is
potential for coastal areas in California to be impacted by a tsunami. According
to researchers at the University of Southern California, a 7.6 magnitude
earthquake under the seafloor near Catalina Island could cause a tsunami to hit
the Southern California coast.
A power outage is the loss of electricity to an
area. A power outage may be referred to as a blackout if power is lost
completely, or as a brownout if some power supply is still present. Blackouts
and brownouts are common in California because of extremely dense populations.
Though power outages are not necessarily considered natural disasters, they
often occur with natural disasters. Power outages are very damaging for
hospitals, since many life-supporting medical devices and tasks require power.
For this reason, hospitals have emergency power generators which are typically
powered by diesel fuel and start automatically when the power goes out.
Heat-related illness can be very dangerous and
affect anyone when temperatures outside get hot enough. The best defense against
heat-related illness is prevention. Drinking more fluids (non-alcoholic and
without caffeine or sugar) can help prevent heat-related illness regardless of
activity level. Taking cool showers or baths, wearing loose and light-colored
clothing and limiting outdoor activity to cooler times of the day can also
prevent illness. Infants and young children, people aged 65 and over, mentally
ill and physically ill people are at a greater risk for heat-related illness and
should be checked on frequently.
For more information please visit the climate change and health equity page with the link above.
For more information on natural disasters visit the Centers for Disease Control and Prevention.