Period 1, Seoyon and Eunice, Weather, Weather Everywhere

WEATHER, WEATHER EVERYWHEREBy: Seoyon Lee and Eunice Choe

AtmosphereThe air you breathe everyday,

whether you breathe it in or blow it out, keeps the earth alive. Did you know this is caused by the atmosphere? Earth's atmosphere is made up of many gases that are important to keep us alive. The three main gases include, oxygen, nitrogen, and argon. Also, Earth is not the only planet in the solar system, but because the gases supply our needs, living on other planets is impossible. You may wonder, why is the atmosphere so important anyway? Well, just consider the atmosphere like there are several layers of blankets covering the earth. If you were Earth and several blankets covered you, they would make you really warm, just like the greenhouse effect makes Earth warm as well.

There are four layers of the atmosphere, they are the Troposphere, Stratosphere, Mesosphere and the Thermosphere.

ConvectionLet's say you're hungry, and you want

to make some soup, so you start heating it up with your pot and stove. As the soup begins to heat up, you are actually seeing convection in action. Convection is the transfer of heat through gases and fluids, and it occurs in the atmosphere, the oceans, and even the sun. During the process of the boiling soup, the soup gets warmer causing it to be less dense and rise. As the warmer water rises, the dense, cooler water begins to sink, replacing the warm water. This cycle continues in a circular motion, making the soup get hotter and hotter. When convection occurs in the atmosphere, the warm air rises and the cool air sinks, eventually making the air warmer.

Wind Currents

Have you ever felt something blow past you but couldn't see what it was? That thing is wind. Wind is the moving air around us. It is caused by the uneven heating of the sun's energy on earth. The different landforms on earth cause the sun's heating to be absorbed unevenly. The different speed and direction of the winds makes each wind special. Warm air is lighter than cool air, so warm air is always above cool air. The patterns the wind moves around the world is called global wind patterns. There are 4 different types of patterns. The first type is doldrums. Doldrums are calm and weak winds that blow near the equator. The second type is trade winds. Trade winds are right above and below the equator. These winds are steady and warm. You can always feel these winds blowing.

The third type is the prevailing westerlies. The prevailing westerlies are also known as horse latitudes. These winds blow right above and below of the trade winds. The prevailing westerlies cause the different weathers to move in the United States and Canada. The prevailing westerlies blow from the west to the east. The fourth and last type of wind is the prevailing easterlies. The prevailing easterlies are closest to the poles. The prevailing easterlies are formed by the cooling of the atmosphere near the poles. The cool air spreads around as it sinks. The prevailing easterlies blow from the east to the west.

Ocean Currents

Have you wondered where the water in the ocean comes from? Well, water is always moving. The continuous movement of water in the ocean is called ocean currents. The water you see in the ocean could have traveled all around the world. The sun's heat on the ocean causes the water to warm and evaporate. The difference in density moves the ocean currents. The ocean currents move clockwise in the Northern Hemisphere and counterclockwise in the Southern Hemisphere due to the Earth's rotation. There are surface currents and deep ocean currents. The surface currents are above the deep ocean currents. The surface currents and deep ocean currents move in opposite directions. As you can see the picture, the warm and cold currents move around the world.

High Pressure and Low Pressure

Have you ever looked at a weather map and seen capital lettered H's and L's? Did you know that those are symbols for high and low pressure?

High Pressure: When the air pressure is high, it is also referred to an anticyclone. The air moves in a clockwise direction as it sinks. High pressure air is denser than low pressure air.

Low Pressure: The low pressure areas are referred to as a cyclone. The air moves in a counterclockwise motion as the less dense air rises.

High Pressure air brings clear skies and sunshine and Low Pressure air brings cloudy skies and wet weather.

Sun and Sun's EnergyEveryday, you can see the sun rise or set and it may not seem important,

but it actually gives the earth energy and heat! The sun provides lots of energy in the earth's atmosphere, and the convection creates winds and ocean currents. Even though it may not seem like it, the sun's energy plays a large role in our lives everyday!

FrontsWhat is a front?Have you ever heard somebody tell you that a warm or cool front is coming in? When two air masses collide, there is a boundary that is formed where the air has trouble mixing with each other. The boundary that forms as the air masses collide is called a front.

Cold FrontWhen fronts bring in cool air, it is called a cold front. The cool air masses that come in move faster than the warm air. Because of the speed, it quickly replaces the warm air that rises. Cold fronts bring thunderstorms, heavy rain, and cloudy skies.Warm FrontWhen the air masses come together, the warm air starts to push over the cool air. The warm air is moist, replacing the cool air that is dry. The warm fronts bring in light rain, fog, and humidity.

Stationary Fronts and Occluded Fronts

Stationary FrontsWhen warm and cold air masses meet, neither replace on another. This causes the water vapor in the warm air to condense into rain, snow, fog, or clouds.Occluded FrontsIn an occluded front, a war air mass is caught between the cool air masses. During the process, the cool air moves underneath and the warm air gets pushed up. The temperature gets cooler because the cool air masses meet in the middle and the warm air gets cut off. As a result, the weather is cloudy, rainy or snowy.

Hurricanes

Have you ever heard of a hurricane? A hurricane is a storm made of water that brings wind and rain. It can be up to 600 miles wide and can travel up to 200 mph. That's fast as a race car. Hurricanes usually lasts up to one week. The center of the hurricane is the "eye." The "eye" is the calmest part. In the Northern Hemisphere, hurricanes rotate counter-clockwise. In the Southern Hemisphere, hurricanes rotate clockwise. Hurricanes can only be formed if the temperature of the ocean water is 80°F or warmer. The wind must also be blowing in the same direction and speed. The hurricane rises as the winds blow above the water causing the storm to rise. When hurricanes reach land, they can damage cars, houses, and people.

Hurricane season is the months when the most hurricanes occur. In the United States, there are two different hurricane seasons. The first is the Atlantic hurricane season. This is between June 1 to November 30. However, most of the hurricanes happen during the autumn months. The Eastern Pacific hurricane season takes place during May 15 to November 30. Did you know that hurricanes also have names? Every year, hurricanes are named alphabetically. This means that the first hurricane's name will start with an "A," the second hurricane's name will start with a "B" and so on. Each name alternates between a girl's and a boy's name. If the year is an odd number, then the year will start with a boy name. If the year is an even number, then the year will start with a girl name.

Typhoons, tropical cyclones (or just cyclones), and hurricanes are the same thing expect the location. Hurricanes are called typhoons in the Western Pacific Ocean (around Japan). Hurricanes are called tropical cyclones (or just cyclones) in storms in the Indian Ocean (around India). Hurricanes are called hurricanes in the Atlantic Ocean and Eastern Pacific Ocean (around the United States). In the United States, hurricanes are called hurricanes.

TornadoesHave you ever seen a big gray funnel shaped object in a movie? That object is called a tornado. Tornadoes can have wind speeds that go up to 300mph. A tornado is storm that extends from the ground to the sky. Near the ground, it is a thunderstorm, and in the sky it is a column of rotating wind. Tornadoes can destroy houses, trees, cars, and about everything else. An average of 1,000 tornadoes are reported every year. Most tornadoes are formed from thunderstorms. Thunderstorms are formed by mixing warm moist air and cool dry air. When the two winds meet, it creates a disturbance in the atmosphere. With a chance in wind direction and an increase in wind speed, an invisible horizontal spinning effect will be formed in the lower atmosphere. The rising will move the spinning effect from being horizontal to vertical. Lots of low level moisture is needed.

A "trigger" (like a cold front) is also needed to lift the moist air. Once the air starts to rise, it continues to rise and get bigger if the atmosphere is unstable. Unstable atmospheres get colder as you go up. Tornadoes are finally formed when the winds at all of the levels of the atmosphere are strong enough and start spin in a clockwise direction. A funnel cloud is something that looks similar to a tornado. Funnel clouds are in the air and do not touch the ground. However, once the funnel cloud touches the ground, it is a tornado. The way tornadoes form, grow, and stop are still a mystery, but with new technology and bright new scientists the mystery will be solved one day in the future.

Isotherm & Isobar

Have you ever heard the weather man or lady say the word isotherm or isobar? The prefix "iso" means equal. The root "therm" means temperature. An example of this is the word thermometer. A thermometer measures temperature. So, the word isotherm means equal temperature. The root "bar" means weight or pressure. An example of this is the word barrel. A barrel is heavy. The word isobar means equal weight or pressure.

Types of PrecipitationWhen you think of precipitation, you may think of rain. Yes, rain is a type of precipitation, but so is snow, sleet, and hail.

Rain:Moisture condensed that fall in rain drops

Snow:Water vapor that have been frozen into ice crystals that fall in flakes

Sleet:Rain with ice. Sleet is snow that has melting while it was falling

Hail:Spherical/Irregular pellets of frozen rain

Types of CloudsWhen you look up in the sky, do you sometimes see white, puffy, fluffy shapes in the sky? These shapes are called clouds. Clouds are made up of tiny water or ice droplets in the sky. These droplets come from water vapor. Water vapor is an invisible gas around us. Clouds are formed when the water vapor condenses on tiny dust particles in the sky and surrounds the dust particle, creating a droplet around the dust particles. When billions of these tiny droplets come together, it forms a visible cloud. A cloud is white, because of the sunlight reflection of the cloud. Have you ever pointed a flashlight at a mirror? The light seems to bounce of the mirror. That is the same thing with clouds. The clouds reflect the sunlight back. Sunlight is made up of every color of the rainbow. Clouds appear white, because when all the colors of the rainbow are put together, you get white.

There are many different types of clouds, but there are three common ones. The first one is cirrus clouds. Cirrus clouds are the most common type of clouds. They are usually white and look thin, wispy, and feathery. Cirrus clouds are composed of ice crystals. Ice crystals are frozen droplets of water. Most of the time, cirrus clouds indicate fair weather. Cirrus clouds are highest in the sky. They sometimes are signs that bad weather is coming.

Stratus clouds are another type of clouds. Stratus clouds are sometimes gray and looks like fog in the sky. They usually cover the entire sky. Stratus clouds typically bring light rain or mist. Stratus clouds are also made of ice crystals. They form in layers. Stratus clouds can form after a fog has "lifted." Fogs and mists form because of stratus clouds.

The last type of clouds is the cumulus clouds. Cumulus clouds are white and fluffy. They resemble cotton balls and have flat bottoms. Cumulus clouds are often called "fair weather clouds." The top of these clouds look like cauliflowers. Despite usually bringing fair weather, cumulus clouds can turn into storm clouds. They can bring short and heavy rainfall.

Dew Point

Have you ever seen water droplets outside early in the morning? That's dew! Dew point is the temperature when condensation or water droplets start forming. Dew can be seen easily on cups. When you pour an icy cold drink, your cup will most likely start to have water droplets on the outside. Those water droplets are dew. The temperature from when the water droplets form on the cup is the dew point.

How Scientists Get Images

Scientists who study weather, get information through satellite images. These images can predict what kind of weather patterns could take place in the future, after looking at the change over time. Different images give different information about weather patterns, such as how clouds are moving and the direction wind is blowing.

Meteorological InstrumentsDo you often wonder how the people on television know how it will rain in the afternoon? Scientists, especially meteorologists, use many different devices to predict and calculate the weather. Meteorologists are scientists who specialize in just studying the weather.

Thermometers are used to show what the air temperature is. Temperature is how cold or hot it is outside. Temperature can be measured in different ways, but the two most common ways are by Celsius and Fahrenheit. In the United States, temperature is measured by using Fahrenheit. The symbol °F means degrees Fahrenheit. The liquid inside a thermometer moves whenever the temperature changes. The liquid is usually colored alcohol or mercury. If it get warmer, the liquid gets bigger and moves up. If it get colder, the liquid get smaller and moves down.

Barometers are used to measure air pressure. The barometer tells you whether the pressure is rising or falling. Rising pressure indicates sunny and dry weather. Falling pressure indicates stormy and rainy weather. Weather vanes tell what direction the wind is blowing. Weather vanes are usually shown in movies to have a rooster on it. The weather vane turns to which direction the wind blows. Anemometers measure how fast the wind is blowing. The cups catch the wind and that turns the dial which shows the number of how fast the wind is blowing.

Weather Map

Who did WhatEunice: Seoyon:Atmosphere Wind CurrentsConvection Ocean CurrentsHigh Pressure HurricanesLow Pressure TornadoesSun and Sun's Energy Isotherm and IsobarFronts Types of CloudsTypes of Precipitation Dew PointHow Scientists Get Images Meteorological Instruments

Weather Map: Together