Earth Science - Chapter 7, Continued

Earth Science- Chapter 7

Storms- natural disasters are the greatest cause of life loss per year, which are storms. Why do storms cause such tremendous life loss? Because they contain a tremendous amount of energy. Where is this energy from? Storm clouds. Inside every cloud, every gram of water has 540 calories of potential energy. When it’s released, this is a lot of energy.

1. Thunderstorms-
1. When do thunderstorms occur? Occurs in the summer.
2. How does it happen? The air of a thunderstorm is warm and moist. The air is formed by a cold front that comes along and pushes a warm front up and causes condensation. This condensation causes cumulus clouds, which cause thunderstorms.
3. How long do they last? Thunderstorms usually last on average less then 1 hour.
4. What are the results of a thunderstorm? The results of a thunderstorm are:

1. Rain

2. Thunder

3. Lightning

4. Hail

2. Tornados-
1. When do tornados occur? Occurs in the spring and early summer.
2. How does it happen? A mT air mass from the Gulf of Mexico collides with a cold, dry air mass from the N. The warm air bangs into the cold air and you have a tornado.
3. Tornado winds are difficult to measure. Why is that?

1. A tornado is very small. The diameter of a tornado could be 1/3 of a mile.

2. A tornado occurs very quickly. An entire tornado could take all of 10 minuets.

3. The winds are extremely fast and they knock down everything in their path.

Tornados do have an average wind speed of about 300 mph. They are measure through radar and observation.

3. Hurricanes-
1. What is a hurricane? A storm that develops over warm, moist ocean water. The center of a hurricane is low-pressured air, and near the center in high-pressured air. The difference in air pressure results in large pressure gradient- results in strong winds. The high-pressured winds swirl around the low-pressured winds in a counterclockwise movement. The result is a low-pressure system. The center of the hurricane is called the eye of the hurricane and it’s always very calm.
2. How does a hurricane develop? It begins as a tropical depression- area of very low pressure that develops in the late summer/early fall over the Atlantic Ocean between South America and Africa. This area has such low pressure because it has lots of solar energy from the warm water; therefore the air above it is very warm. The storm gathers strength as it passes over more of the Atlantic Ocean. When the winds of this storm reach 74 mph, it changes from a tropical depression to a hurricane. (Tropical depression- tropical storm- hurricane- major hurricane)
3. What is the path of a hurricane? It begins in the tropical water near the equator. It travels to the mid latitudes (30- 60). It curves with the prevailing W winds.
4. What are the results of a hurricane?

1. Very fierce winds

2. Intense precipitation

3. Storm surge- extremely high tides

4. When it comes ashore, it causes tremendous damage.

5. How long does it take for a hurricane to lose power? Because of its tremendous size, it takes many hours for a hurricane to pass. A tornado can form within an intense hurricane. When a hurricane is deprived of its main source of energy, which is warm, tropical water, it begins to lose power. Once it’s on the land, its energy will only last for a few days and it will eventually turn into a mid latitude cyclone.
3. Blizzards-
1. What is a blizzard? A winter snowstorm that produces very heavy snow. The winds speed is 35 mph.
2. Where do blizzards occur?

1. The coastal regions of NY because the Atlantic Ocean brings a lot of water vapor into land which will rain down as snow.

2. Areas near the Great Lakes are subject to “lake effect snow”.

3. What are the results of a blizzard?

1. Paralyzes cities

2. Hard to pass by on roads

3. Tremendous loss of body heat

4. People can get frost bitten.