Download TSUNAMI! Destructive waves!

TSUNAMI! Destructive waves!
The tsunami is a sequence of waves that can reach
heights of several tens of meters and sweep away
everything in its path; it is produced mostly by strong
submarine earthquakes occurred near the coastal area
In Mexico, during the last 280 years, 65 tsunamis have
hit the Pacific coast, with waves up to 10 meters in
height, therefore, it is important to be informed about the
directions of Civil Protection authorities
At any
sign, attend
directions of the
Civil Protection
authorities
Preventive measures
IF YOU LIVE NEAR THE COAST
OR IF YOU TRAVEL TO THE BEACH
• Investigate the height above the sea
level of the place where you live
• Identify evacuation routes towards
high places
• Prepare a family evacuation plan and
protect children, elder people and
animals
• Identify tall buildings and places that
will serve you as temporary shelter
Learn more
Center for Scientific Research and Higher
Education of Ensenada, Baja California
www.cicese.edu.mx
National Center for Disasters Prevention
www.cenapred.gob.mx
Tsunami Warning Center
digaohm.semar.gob.mx/CAT/codes/
centroAlertasTsunamis.html
Recommendations
WARNING SIGNS
AT THE BEACH
WHAT TO DO IF A TSUNAMI IS COMING?
• A strong earthquake, although
not all of them
produce a
tsunami
• The sea goes
away from the
beach exposing
the seabed
• The water
becomes foamy
1
• Keep calm
2• Stay away from
the beach, rivers,
streams, wetlands
or coastal lagoons
and be sheltered in
the highlands
3• Do not stop to
observe the
seafloor
#PrevenirEsVivir
MOVING MEXICO INTO PREVENTION
4• If you are on a
boat, refrain from
reaching a port; at
offshore the risk is
lower
5• Do not use your
vehicle to evacuate
6• Avoid bridges over
water bodies
Source: National Center for Disaster Prevention
Tsunami or Maremoto
Comparativa de velocidad de las olas con medios de transporte
The earthquake is the alert!
What is it?
Stages of a tsunami
Natural phenomenon which destroys littorals due to wave
action caused by a strong earthquake in the seabed. The
Japanese word tsunami means "harbor wave". It is also
called maremoto, a Latin word for "sea in motion”
Generation
Earthquakes lift vertically the earth
crust at the seabed
Mexico is at the "Circum-Pacific belt" or "Ring of Fire",
geologically active zone that causes 80% of the tsunamis
Propagation
Tsunami waves travel at high speeds
(800 km/h) on the open sea, for
example, with 5,000 meters depth.
This velocity decreases to 35 km/h
when approaching the coast, with 10
meters depth
Flooding
The waves increase when they
reach the coast. Not always the
first wave is the highest, sometimes
it is the third or fourth one, and
they devastate everything on its
path, reaching up to 10 km inland
Location of Circum-Pacific Belt or Ring of Fire
Trenches
800 km/h
250 km/h
100 km/h
35 km/h
5,000 m
500 m
100 m
10 m
Depth
Ocean bed
Types of seismic tsunamis
Local: They originate along the coast and penetrate
large distances inland in a short time
Regional: They originate 1,000 kilometers away from
the country and arrive within a time span of three hours
Distant or transoceanic: They originate in the western
margin of the Pacific Ocean and take between eight and
ten hours to reach the coasts of Mexico. They can cause
great damage if the magnitude of the earthquake is
greater than eight
Hazard of tsunamis in Mexico
High*
Medium
Low
*Distant tsunami
generating-and-receiving area
Alerts
Due to the hazard of tsunamis in Mexico, the
National Tsunami Warning System (SINAT)
was created, hosting the Tsunami Warning
Center (CAT) in charge of the Mexican Navy,
to analyze and process both the seismic and
sea level data in real time. The CAT sends
bulletins to the Civil Protection authorities in
order to alert the population promptly