Weather, What is it All About?

A Childrens Inquisitive Informational Book By: Luka Zrnic and

Andrew Hatanpaa

What is Weather?

Weather is the condition at which the atmosphere is in. Weather measures whether it is hot or cold, raining or snowing, and other things like that.Weather should not be confused with climate, which is the average weather condition over a longer period of time, such as a month.

The Earth's Atmosphere and What Does it do?

The atmosphere is a layer of gases that protects the earth and the people that inhabit it, just like a force field for a superhero. It controls the temperature and keeps it mellow, while at the same time absorbing the dangerous rays which the Sun can emit.

The Layers of the AtmosphereThe Atmosphere also has layers which divide it into five parts.The first and the closest to the surface of these is the troposphere. It is where weather takes place.The next layer is the stratosphere, a stable layer where planes fly.The third layer is called the mesosphere, which is where all the meteors that fall to earth burn up and disappear.

The Layers of the Atmosphere cont.

The fourth layer is called the thermosphere. This layer is home to the northern aurora lights and it is where space shuttles orbit.The fifth and final layer is named the exosphere. It is a very thin layer which merges into space.Note that as the layers ascend they actually become thinner and thinner.

What are Wind Currents?

Wind moves from high pressure areas to low pressure areas. If the air in an area is hot, it becomes a high pressure zone. If it is cold, it becomes a low pressure zone. Since the poles are colder than the equator, air tends to move from the equator to the poles. Areas of low pressure are denser than areas of high pressure.

Wind Currents Cont.Since the poles are colder than the equator, air tends to move from the equator to the poles. Areas of low pressure are denser than areas of high pressure, due to the fact that they are colder.When the air moves, winds are formed on the earth's surface.In addition, there are winds called easterlies which travel from east to west, and westerlies which travel from west to east around the globe.

High Pressure and How it Affects Weather

High Pressure is air to is making have a higher density, ultimately causing it to sink. As it sinks winds move outward in a clockwise circle. High pressure air forms Anticyclones and harbors stable weather conditions. A day that has high pressure air can have the weather conditions as follows: clear and sunny skies, dry weather, hot weather, and sometimes fog and mist.

Low Pressure and How it Affects WeatherLow Pressure is the exact opposite of high pressure. It is not compressed and as a result it is less dense causing the air to rise. As the air rises winds spiral inward in a counter-clockwise direction. During low pressure cyclones can be formed and there are usually unstable atmospheric conditions. Weather such as cloudy skies, wet weather, and rapidly changing weather can occur during days of low pressure.

Types of Fronts- Warm and ColdThere are actually 4 types of fronts:Cold Front- fast moving cold air collides with slow moving hot air resulting in the cold ducking underneath the warm air. Usually produce cloudy skies and thunderstorms.Warm Front- A warm front includes fast moving warm and and slow moving cold air making the cold air duck under, yet again. Results in windy and stormy weather. And...

Types of Fronts-Stationary and OccludedOccluded Front- An occluded front occurs when a warm air mass is caught between two cold air masses and as a result the warm air rises above the cold air and is cut-off from the ground. The ground then has cold air, and weather such as clouds and snow can occurStationary Front- A front where a warm and cold air mass of equal power collide, resulting in a tie and no mass ducking over or under. These fronts can last days and can cause long periods of cloudiness and precipitation.

How Clouds are FormedClouds are formed when evaporated water cools below its dew point around a surface, such as dust. A dew point is the temperature where water "de-evaporates," or condenses. Since the temperature is colder the farther you go from the ground, clouds are usually up high. Low clouds (ground level) are called fog.

There are many types of clouds so try to keep up!Despite that most clouds are mostly water, they do not all look the same and definitely do not the same types of weather.Clouds can be classified by how they look, what they do, and at what altitude they appear.

Almost All of the Different Types of Clouds

Low Clouds-Stratus

These clouds are ones that appear relatively low in the atmosphere and usually don't precipitate.The first low cloud would be a stratus cloud which appears around 6,000 feet above the surface. These clouds are thin and stretched out over long distances

Low Clouds-Stratocumulus

Stratocumulus clouds also appear around the 6,000 ft. mark. They are stretched just as the stratus clouds are but take on a more puffy appearance like the cumulous cloud. Just as most low clouds stratocumulus clouds can sink to the surface of the Earth and become fog. These clouds, just as their partners(cumulus and stratus) do not precipitate.

Low Clouds-CumulusCumulus clouds are much more compact than the other two low clouds and are more puffy. These clouds don't precipitate, and are usually the most common type of clouds that you seen on a normal day. Interestingly, if they collect an excess of water vapor they can transform into cumululonibus clouds and produce large amounts of precipitation as they are growing.

Middle Clouds-Altocumulus and AltostratusAltocumulus and Altostratus clouds both exist between 6,000 and 19,000 feet, making them mostly middle clouds. Altostratus clouds are very long, as well as extremely thin. They do not precipitate. Altocumulus clouds form in large clusters of small puffy clouds. There can be up to 50 of them in a single cluster. Like the altostratus clouds, they do not produce precipitation.

AltocumulusClouds

Altostratus Clouds

High Clouds-Cirrus and CirrocumulusThese clouds float over 18,000 feet above the ground, making them high clouds. Like the middle clouds, these two do not precipitate. Cirrus clouds are large thin clouds that stretch a long way in every direction, giving them a spider-like appearance.Cirrocumulus bear a very large resemblance to altocumulus clouds, by forming clusters, however these clouds are smaller than atlocumulus.

Cirrocumulus Clouds

Cirrus Clouds

Special Clouds- Cumulonimbus

Cumulonimbus clouds are very large clouds that range in every single category mentioned until now. These clouds do have the ability to precipitate and to release vast amounts of rain, snow sleet, or hail depending on the temperature.

Types of Precipitation

Snow, rain, hail, and sleet are the things that usually fall out of the sky when a cloud's water clumps up too much for the cloud to hold it. This occurs during condensation. The water's state of matter as it falls depends on the temperature.

What Are Ocean Currents?The Ocean and its waters are always moving, they cycle due to convection and because of this constant movement sailboats and other boat can move throughout the ocean. There many types of currents in the ocean.Upwelling Current- cold nutrient rich water rises up from the deep and replaces the surface water due to the earth's rotation and strong seasonal winds.Gulf Stream- the main hot water current. It is strong fast and circulates around tropical coastal areas.

What are Weather Maps?Weather maps are maps that show the meteorological events happening in a certain area for a certain period of time using different symbols. Weather maps show things like temperature,fronts, pressure, precipitation, and humidity.Many news shows on T.V. show weather maps to people, giving them a visual and informational picture of weather.

What are Tornadoes and How are they FormedTornados are columns of swiftly rotating air and winds that can reach speeds of 300 mph. They are an extension from a thunderstorm and reach to touch the ground. Warm, moist air collides with cold and dry air resulting in an instability in the atmosphere. This change in wind direction and speed causes a spinning effect in the lower atmosphere, thus forming a tornado.

Hurricanes Hurricanes are enormous wind storms that spiral from 75 to 200 miles per hour. They usually form over water gathering heat and energy from it. The evaporation of seawater increases the power of the storm. In the northern hemisphere hurricanes rotate counter-clockwise, while in the southern hemisphere they rotate clockwise.

Southern Hemisphere

NorthernHemisphere

Isotherm and Isobar

Isobars are lines on a weather map that join places that have the same amounts of pressure

Isotherms are lines on a weather map that join places that have the same temperature.

The Sun and its Energy

Almost all of the Earth's energy comes from the Sun, through EM or electromagnetic waves. There are actually different types of waves that the Sun emits; such as visible light, infrared waves, and UV or ultraviolet waves. We actually process the Earth's heat through its UV rays, which can be harmful, but luckily the atmosphere can absorb most of them.

Interesting Fact- The Earth receives 1/2 billionth of the sun's total energy emitted

Convection, How does it Affect the Ocean?In a pot heated from underneath, water on the bottom heats up, then rises, then forces the cold water (which is denser) to the bottom. This cycle repeats until the pot is no longer heated. A similar thing happens in the ocean. Cold water sinks from the top of the ocean, while warm water rises from the bottom. The Earth's mantle is the "stove."

How Do Scientists Get These Pictures?This is actually a rather easy thing to explain. Scientists require the help of satellites that orbit the earth. These satellites take aerial pictures of weather happenings such as storms and hurricanes. These images are then taken from the satellites and used by the scientists.

What instruments do Scientists Use?Meteorologists use many instruments to measure and monitor weather such as:Thermometer- an instrument that measures air temperature. It has a glass container that contains either liquid alcohol or mercury. There is a scale that measures the temperatureBarometer- a device that records air pressure and tells whether air pressure is rising or falling. Rising pressure means sunny weather and falling means stormy or cloudy weather

What Instruments Do Scientists Use?Rain Gauge- an instrument that measure the amount of rain fallen over a certain period of timeWind Vane- determines the direction in which the wind is blowingAnemometer- measures wind speed with cups rotating on a dial. As the wind blows cups rotate and the dial measures the wind speedHygrometer- measures levels of humidity and water vapor in the air

What Instruments Do Scientists Use? Weather Balloon- an instrument that show the weather in a high section of the atmosphere.Sling-Psychrometer- Uses the cooling effect produced by evaporation to compare relative humidityCompass- an instrument uses to show location in accordance with direction