Introduction to Natural Hazards

NATURAL DISASTERS

By Ciara Paddayuman

OBJECTIVE

​Using the internet, search for a news about a particular natural disaster and its effect to the place where it happened.

Visit the google classwork

A natural disaster is any event by the earth that causes massive damage or loss of life. Usually are once in a while incidents​

NATURAL DIASTERS​

• Catastrophic events caused by nature.

• Cause changes to Earth’s surface.

• Can have a positive and negative impact on Earth.

• Very hazardous to living organisms.

• Natural Hazard - an event that can cause major damage and cause injury or death to living organisms.

​What is a Natural Disaster?

Multiple Choice

What is a Natural Hazard?

• A natural event that poses a threat to people, property, and the environment
• An event caused by supernatural forces
• A harmless natural occurrence with no impact on humans
• A man-made disaster caused by human activities

EXAMPLES OF A NATURAL DISASTER

• Earthquakes

• ​Floods

• Hurricanes

• Tornados

• Tsunamis

• Wild Fires​

Open Ended

Write about a time where you experienced, or lived through a Natural Disaster

​EARTHQUAKES

Earthquakes are the shaking of the Earth's surface caused by the sudden release of energy along faults or fractures in the Earth's crust.

Most earthquakes are caused by the movement of tectonic plates, When stress builds up along faults where these plates meet, it can cause them to suddenly slip or move, resulting in seismic waves that propagate through the Earth.

stress= volcanic activity, landslides, and human-induced factors such as mining or reservoir-induced seismicity

Multiple Choice

How do earthquakes occur?

• By a sudden release of energy in the Earth's crust
• By the temperature of the ocean
• By the rotation of the Earth
• By the movement of the moon

Earthquake

​Valdivia Earthquake​

Magnitude: 9.5

Date: ​May 22, 1960

Location: ​Bio-Bio, Chile

Impact: ​

​Approximately 1,655 killed, 3,000 injured, 2,000,000 homeless, and $550 million damage in southern Chile; tsunami caused 61 deaths, $75 million damage in Hawaii; 138 deaths and $50 million damage in Japan; 32 dead and missing in the Philippines; and $500,000 damage to the west coast of the United States.

https://www.youtube.com/watch?v=DFLLtVPzwGA

FLOODS

A flood is generally a temporary condition. A flood occurs anytime two acres of usually dry land is covered in water. Floods can result from hurricanes, heavy rains, or levee and dam failures. ​

Earth Science

Natural Disaster

Multiple Choice

How do floods occur?

• By an overflow of water onto land that is usually dry.
• By a sudden decrease in the water level
• By a lack of water in the area
• By a sudden increase in the temperature

Earthquake

​2022 KwaZulu-Natal floods​

Date: ​April 11-13, 2022

Location: ​South Africa

Impact: ​

​

​​​On 11-13 April, severe flooding and landslides caused by heavy rainfall affected southern and south-eastern South Africa, particularly the Provinces of KwaZulu-Natal and Eastern Cape. According to national authorities, 443 people died in KwaZulu-Natal and over 40,000 are missing. More than 40,000 people have been displaced, while nearly 4,000 houses were destroyed and more than 8,000 others were damaged, mostly across Durban City and its surrounding areas. A National State of Disaster has been declared in response to the floods and landslides, and rescue teams have been deployed to the affected areas to provide humanitarian assistance to those most affected. The International Disaster Charter 755 was activated for South Africa. On 19-20 April, moderate rainfall is forecast over north-eastern South Africa, while no heavy rainfall is expected over the already affected Provinces.

​https://www.youtube.com/watch?v=JDciB9sNlfg

HURRICANES

Hurricanes are large, powerful tropical storms characterized by strong winds, heavy rainfall, storm surges, and potential flooding. They form over warm ocean waters and are known as cyclones or typhoons in other parts of the world.They usually dies down after hitting land.

Form over warm ocean waters, with low wind shear and high atmospheric instability.

Earth Science

Natural Disaster

Multiple Choice

Where does a Hurricane form?

• In the middle of a city

• In the desert
• On top of a mountain
• Over warm ocean waters near the equator

Earthquake

​Typhoon Yolanda​

​Year Formed: 2013

Type: Category 5 Super Typhoon

Highest Wind Speed: 195 mph

Diameter: 800 km

​While Yolanda, also known as Typhoon Haiyan, is the smallest on this list, it is one of the strongest storms ever. It is by far the deadliest storm to hit the Philippines, accounting for over 6,000 fatalities and two billion USD in damage in that country. Yolanda also caused great damage in several other nations in the region as well as South China and Vietnam in Southeast Asia.

​https://www.youtube.com/watch?v=KTbhAp7kpPU

TORNADOS

A tornado is giant funnel of wind with speeds that can be around​ 300 mph. They are created when hot air meets cold air.

Tornadoes typically form in severe thunderstorms when warm, moist air near the surface interacts with cold, dry air aloft, creating instability in the atmosphere. Wind shear, which is a change in wind speed and direction with height, can cause the rotating updraft within the storm to tilt and eventually spawn a tornado

"Tornado Alley" is a colloquial term used to describe an area in the central United States that is particularly prone to tornado activity. While it is not an officially defined region, Tornado Alley typically includes parts of Texas, Oklahoma, Kansas, Nebraska, South Dakota, Iowa, and eastern Colorado.

Clash of Air Masses: Tornado Alley is situated where warm, moist air from the Gulf of Mexico collides with cool, dry air from the Rocky Mountains and the northern Plains. This clash of air masses creates an environment conducive to the formation of severe thunderstorms and tornadoes.

Flat Terrain: The relatively flat terrain in Tornado Alley allows warm, moist air to flow unimpeded from the Gulf of Mexico, promoting the development of strong thunderstorm systems capable of producing tornadoes.
Dryline: Tornado Alley is often affected by a weather phenomenon known as the dryline, which separates moist air to the east from dry air to the west. The convergence along the dryline can enhance thunderstorm development and increase the likelihood of tornado formation.

Tornado-Prone Weather Patterns: Tornado Alley frequently experiences weather patterns, such as cold fronts, warm fronts, and low-pressure systems, that are conducive to the development of severe thunderstorms and tornadoes.

TORNADO ALLEY

Multiple Select

Where Does Tornadoes form?

• OverWater

• OverLand

• Tornado Alley
• Inside Thunderstorms

Earthquake

​El Reno Tornado​

​Year Formed: May 2013

Speed: 302 mph (486 kph)

Diameter: 2.6 miles (4.2 km)

The tornado that hit El Reno, Oklahoma, was as wide as Manhattan, spun off subvortices as fast as NASCAR drivers circle a track, and had some of the strongest winds ever measured. It took the lives of three highly experienced storm chasers.

https://www.youtube.com/watch?v=Q7X3fyId2U0​

TSUNAMIS

A tsunami is a series of giant waves capable of flooding areas and destroying buildings.

When an earthquake occurs beneath the ocean floor, it can cause the seafloor to uplift or subside, displacing large volumes of water and generating tsunami waves that travel across the ocean at high speeds.

Natural Disaster

Multiple Choice

how does a tsunami form?

• A tsunami forms from the melting of polar ice caps
• A tsunami forms when a meteor strikes the ocean
• A tsunami forms due to a sudden displacement of a large volume of water, often caused by an underwater earthquake or volcanic eruption.
• A tsunami forms due to excessive rainfall

Earthquake

​The Great Tohoku Earthquake​

​Year Formed: March 11, 2011

Place: Northeastern Japan​

Speed: 302 mph (486 kph)

Diameter: 2.6 miles (4.2 km)

The Japan earthquake and tsunami of 2011, also known as the 2011 Tohoku earthquake and tsunami or the Great Tohoku earthquake, was a natural disaster that shook northeastern Japan on March 11, 2011. The disaster began when a magnitude-9 earthquake shook the region in the early afternoon, unleashing a savage tsunami.

The effects of the great earthquake, which was the strongest in Japan's recorded history, were felt around the world, from Norway's fjords to Antarctica's ice sheet. Tsunami debris has continued to wash up on North American beaches

https://www.youtube.com/watch?v=oWzdgBNfhQU​

WILDFIRES

Wild fires are large fires that burn many acres at a time.

Ignited by sources like lightning, human activities, or volcanic eruptions.

Dry conditions, hot temperatures, and wind can cause fires to spread quickly.

Natural Disaster

Multiple Choice

how do wildfires occur?

• Wildfires occur due to excessive rainfall and low temperatures
• Wildfires occur due to a combination of dry conditions, high temperatures, and ignition sources such as lightning or human activities.
• Wildfires occur due to lack of oxygen and high humidity
• Wildfires occur due to volcanic eruptions and heavy snowfall

Earthquake

​Australia's Worst Wildfire​

​Year Formed: June 2019 - May 2020

Place: Australia

Cost: over $103 billion (2020 AUD)​

Diameter: 2.6 miles (4.2 km)

Burned Area: Approximately 24,300,000 hectares

Deaths: 34 direct; 445 indirect (smoke inhalation)​

https://www.youtube.com/watch?v=Iaxc2RuRnCQ​