Science

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Earthquakes are the vibrations caused by rocks breaking under stress. The underground surface along which the rock breaks and moves are called a fault plane.

The focus, or “hypocentre”, of an earthquake is the point where it originated within the Earth. The point on the Earth's surface directly above the focus is called the earthquake epicentre. The size or magnitude of earthquakes is determined by measuring the amplitude of the seismic waves recorded on a seismograph and the distance of the seismograph from the earthquake. These are put into a formula which converts them to a magnitude, which is a measure of the energy released by the earthquake. For every unit increase in magnitude, there is roughly a thirty-fold increase in the energy released. For instance, a magnitude. Earthquake magnitude was traditionally measured on the Richter scale. It is often now calculated from the seismic moment, which is proportional to the fault area multiplied by the average displacement on the fault. The focus of an earthquake is the point where it originated within the Earth. The point on the Earth's surface directly above the focus is called the earthquake epicentre.

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Earthquakes are the vibrations caused by rocks breaking under stress. The underground surface along which the rock breaks and moves are called a fault plane. The focus, or “hypocentre”, of an earthquake is the point where it originated within the Earth. The point on the Earth's surface directly above the focus is called the earthquake epicentre. The sizeFlooding occurs most commonly from heavy rainfall when natural watercourses do not have the capacity to carry excess water. However, floods are not always caused by heavy rainfall. In coastal areas, water inundation can be caused by a storm surge as a result of a tropical cyclone, a tsunami or a high tide coinciding with higher than normal river levels. If a dam fails, triggered for example by an earthquake, the downstream area will flood, even in dry weather conditions. or magnitude of earthquakes is determined by measuring the amplitude of the seismic waves recorded on a seismograph and the distance of the seismograph from the earthquake. These are put into a formula which converts them to a magnitude, which is a measure of the energy released by the earthquake. For every unit increase in magnitude, there is roughly a thirty-fold increase in the energy released. Earthquake magnitude was traditionally measured on the Richter scale. It is often now calculated from the seismic moment, which is proportional to the fault area multiplied by the average displacement on the fault. The focus of an earthquake is the point where it originated within the Earth. The point on the Earth's surface directly above the focus is called the earthquake epicentre.

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Floods

.Flooding occurs from heavy rainfall when natural watercourses do not have the capacity to carry excess water

.floods are not always caused by heavy rainfall. In coastal areas, water inundation can be caused by a storm surge as a result of a tropical cyclone known as a flash flood.

FIND SAFE SHELTER RIGHT AWAY

Do not walk, swim or drive through flood waters. Turn Around, Don’t Drown!

Just six inches of moving water can knock you down, and one foot of moving water can sweep your vehicle away.

Stay off of bridges over fast-moving water.

Depending on the type of flooding:

Evacuate if told to do so.

Move to higher ground or a higher floor.

Stay where you are.

Earthquakes

.Earthquakes are the vibrations caused by rocks breaking under stress.

.The underground surface along which the rock breaks and moves is called a fault plane.

The focus, or “hypocentre”, of an earthquake is the point where it originated within the Earth.

The size or magnitude of earthquakes is determined by measuring the amplitude of the seismic waves recorded on a seismograph and the distance of the seismograph from the earthquake.

These are put into a formula which converts them to a magnitude, which is a measure of the energy released by the earthquake. For every unit increase in magnitude,

-Earthquake magnitude was traditionally measured on the Richter scale. It is often now calculated from seismic moment, which is proportional to the fault area multiplied by the average displacement on the fault.

The focus of an earthquake is the point where it originated within the Earth. The point on the Earth's surface directly above the focus is called the earthquake epicentre.

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Here are some tips for your earthquake readiness plan.

Take some time to discuss evacuation with your family. Sketch a floor plan of your home; walk through each room and discuss evacuation details.

Plan a second way to exit each room or area. If special equipment is needed, mark where it is located.

Mark where your emergency food, water, first aid kits, and fire extinguishers are located.

Store a type-ABC fire extinguisher in an easily accessible location.

Mark where the utility switches or valves are located, and learn how to turn off your gas and water mains, as well as electricity.

Indicate the location of your family’s emergency outdoor meeting place.

Keep several flashlights in easily accessible places around the house.

Keep a wrench or turn-off tool in waterproof wrap near the gas meter.

Know whether you live, work or play in a tsunami hazard zone.

Obtain a NOAA Weather Radio with the Public Alert feature to notify you of tsunamis and other hazards.

Keep a flashlight, slippers and gloves next to beds.

Keep your gas tank at least half full.

Determine safe spaces away from windows in each room of your home. Choose spots where it is unlikely something will fall on you.

Prepare a disaster kit. Stock up on canned food, a first-aid kit, 3 gallons of water per person, dust masks, goggles, battery-operated radio and flashlights.

Cyclones

In meteorology, a cycloneis a large scale air mass that rotates around a strong center of low atmospheric pressure.-

-Cyclones are characterized by inward spiraling winds that rotate about a zone of low pressure

-Upper level cyclones can exist without the presence of a surface low, and can pinch off from the base of the tropical upper tropospheric trough during the summer months in the Northern Hemisphere.

-Cyclones have also been seen on extraterrestrial planets, such as Mars, Jupiter, and Neptune.[7][8] Cyclogenesis is the process of cyclone formation and intensification.

-A cyclone's track is guided over the course of its 2 to 6 day life cycle by the steering flow of the subtropical jet stream.

Disconnect all electrical appliances. Listen to your battery radio for updates.

Stay inside and shelter (well clear of windows) in the strongest part of the building,

i.e. cellar, internal hallway or bathroom. Keep evacuation and emergency kits with you.

If the building starts to break up, protect yourself with mattresses, rugs or blankets under a

strong table or bench or hold onto a solid fixture, e.g. a water pipe.

Beware the calm 'eye'. If the wind drops, don't assume the cyclone is over; violent winds

will soon resume from another direction. Wait for the official 'all clear'.

If driving, stop (handbrake on and in gear) — but well away from the sea and clear of trees,

power lines and streams. Stay in the vehicle.

tornadoes

-A tornado is a violently rotating column of air that extends from a thunderstorm to the ground.

-It's often portended by a dark, greenish sky. Black storm clouds gather. Baseball-size hail may fall.

-A funnel suddenly appears, as though descending from a cloud. The funnel hits the ground and roars forward with a sound like that of a freight train approaching.

-The tornado mostly tears up everything in its path.

Go to the basement or an inside room without windows on the lowest floor (bathroom, closet, center hallway).

Avoid windows.

For added protection get under something sturdy (a heavy table or workbench). Cover your body with a blanket, sleeping bag or mattress. ...

Do not stay in a mobile home.

volcanic eruptions

Volcanoes are Earth's geologic architects.

-They've created more than 80 percent of our planet's surface, laying the foundation that has allowed life to thrive.

-Their explosive force crafts mountains as well as craters. Lava rivers spread into bleak landscapes. But as time ticks by, the elements break down these volcanic rocks,

-liberating nutrients from their stony prisons and creating remarkably fertile soils that have allowed civilizations to flourish.

A natural disaster is a major adverse event resulting from natural processes of the Earth; examples are floods, hurricanes, tornadoes, volcanic eruptions, earthquakes, tsunamis, storms, and other geologic processes.