weather conditions. what makes up earth’s atmosphere? the layer of air surrounds our planet is...
TRANSCRIPT
Weather Weather ConditionsConditions
What Makes up Earth’s What Makes up Earth’s Atmosphere?Atmosphere?
The layer of air surrounds our The layer of air surrounds our planet is called the atmosphere.planet is called the atmosphere.
Layers of the Atmosphere Layers of the Atmosphere
TroposphereTroposphere StratosphereStratosphere MesosphereMesosphere ThermosphereThermosphere
TroposphereTroposphere
Layer closes to the Layer closes to the earthearth
Weather happens in Weather happens in this layerthis layer
Live and breathe air in Live and breathe air in this layerthis layer
Air temperature Air temperature decreases as you go decreases as you go higherhigher
StratosphereStratosphere
Airplanes travel in this Airplanes travel in this layer to avoid bad weatherlayer to avoid bad weather
Contains most of the Contains most of the atmosphere’s ozoneatmosphere’s ozone
Ozone protects living Ozone protects living things from harmful rays of things from harmful rays of the sunthe sun
Temperature increase with Temperature increase with heightheight
MesosphereMesosphere
Temperature decrease Temperature decrease with heightwith height
Coldest layer of the Coldest layer of the atmosphereatmosphere
ThermosphereThermosphere
Hot, outermost layerHot, outermost layer Temperature increase Temperature increase
quickly with heightquickly with height
How Do Air Masses Affect the How Do Air Masses Affect the WeatherWeather
Greenhouse EffectGreenhouse Effect
Air MassesAir Masses
What happens when to air masses What happens when to air masses meet?meet?
When two air masses meet, they form a When two air masses meet, they form a border called a frontborder called a front
A front is the area where two air masses A front is the area where two air masses meet and weather happensmeet and weather happens
Cold FrontCold Front
A cold air mass A cold air mass catches up with a catches up with a warm air masswarm air mass
The cold air mass The cold air mass forces the warm air up forces the warm air up in the atmospherein the atmosphere
As warm airAs warm air
Cold FrontCold Front
As warm air pushes As warm air pushes upward, it cool and upward, it cool and forms cloud. forms cloud.
Rain develops.Rain develops. Thunderstorm often Thunderstorm often
occur along a cold occur along a cold front.front.
Cold FrontCold Front
Generally move from northwest Generally move from northwest to southeastto southeast
Air behind a cold front is colder Air behind a cold front is colder and drier than the air ahead of and drier than the air ahead of it.it.
When a cold front passes When a cold front passes through, temperatures can drop through, temperatures can drop more than 15 degrees within the more than 15 degrees within the first hour.first hour.
Represented by a solid lines Represented by a solid lines with triangles along the front with triangles along the front pointing towards the warmer air pointing towards the warmer air and in the direction of and in the direction of movementmovement
Warm FrontWarm Front
Forms when a warm air Forms when a warm air mass catches up with a mass catches up with a cold air masscold air mass
Warm air slides up over Warm air slides up over the colder, denser airthe colder, denser air
Generally move from Generally move from southwest to northeast southwest to northeast
Air behind a warm Air behind a warm front is warmer and front is warmer and more moist than the air more moist than the air ahead of itahead of it
Represented by a solid Represented by a solid line with semicircles line with semicircles pointing towards the colder pointing towards the colder air and in the direction of air and in the direction of the movementthe movement
Steady rain or snow may Steady rain or snow may fall as the front fall as the front approaches and passesapproaches and passes
Common Characteristics of Warm Fronts
Before PassingWhile Passing After Passing
Winds South-southeast
Temperatures
Pressure
Clouds
Precipitation
Visibility
Dew Point
Clouds and WeatherClouds and Weather Weather scientists classify a cloud based on its shape, its Weather scientists classify a cloud based on its shape, its
color, and where it forms in the atmospherecolor, and where it forms in the atmosphere
CirrusCirrus
A wispy white cloudA wispy white cloud Fair weatherFair weather
CumulusCumulus
Puffy cotton-ball Puffy cotton-ball cloudsclouds
Begins to form when Begins to form when water droplets water droplets condense at middle condense at middle altitudesaltitudes
CumulonimbusCumulonimbus
Dense cumulus cloud Dense cumulus cloud with a hazy outlinewith a hazy outline
Usually producing Usually producing heavy rain, heavy rain, thunderstorms, or thunderstorms, or hailstormshailstorms
StratusStratus
Dark gray clouds that Dark gray clouds that form a low layerform a low layer
Sometimes bring rain Sometimes bring rain or snow showersor snow showers
What is a Cycle?What is a Cycle?
A sequence of events A sequence of events that repeat themselvesthat repeat themselves
EvaporationEvaporation
The sun heats up water in The sun heats up water in rivers, lakes, or oceanrivers, lakes, or ocean
The water changes from a liquid The water changes from a liquid into a gas, vapor, or steam.into a gas, vapor, or steam.
The water vapor leaves the The water vapor leaves the rivers, oceans, or lakes and rivers, oceans, or lakes and goes into the atmosphere.goes into the atmosphere.
CondensationCondensation
Water vapor in the air Water vapor in the air gets cold and changes gets cold and changes back into liquidback into liquid
forming cloudsforming clouds
TranspirationTranspiration
Is the process by which plants Is the process by which plants return water to the atmosphere.return water to the atmosphere.
After absorbing water from the After absorbing water from the ground, plant release water ground, plant release water through their leaves.through their leaves.
This helps plants stay cool.This helps plants stay cool.
Precipitation Precipitation
Occurs when so much Occurs when so much water has condensed that water has condensed that the air cannot hold it the air cannot hold it anymore.anymore.
Clouds get heavy and Clouds get heavy and water falls back to earth in water falls back to earth in the form of rain, sleet, hail, the form of rain, sleet, hail, or snowor snow
What instruments do meteorologist What instruments do meteorologist use to forecast weather?use to forecast weather?
AnemometerAnemometer
Measures wind speedMeasures wind speed The cups catch the The cups catch the
wind, turning a dial wind, turning a dial attached to the attached to the instrument.instrument.
The dial shows the The dial shows the wind speed.wind speed.
BarometerBarometer
Measures air pressureMeasures air pressure
Psychrometer Psychrometer
Measures relative Measures relative humidity, using the humidity, using the cooling effect of cooling effect of evaporationevaporation
HygrometerHygrometer
Measures the amount Measures the amount of humidity in the air.of humidity in the air.