Presentation on theme: "Intro to WeatherIntro to Weather Clip Weather by Brainpop 1) What cycle is the basis of our weather? 2) What causes precipitation to occur? 3) Where."— Presentation transcript:
Intro to WeatherIntro to Weather Clip
Weather by Brainpop 1) What cycle is the basis of our weather? 2) What causes precipitation to occur? 3) Where do storms usually occur?
Weather Temporary behavior of atmosphere (whats going on at any certain time) Small geographic area Can change rapidly
Weather --The study of weather is meteorology --Someone who studies weather is called a meteorologist
Climate Long-term behavior of atmosphere (100+ years) Large Large geographic area slow Very slow to change
POLAR 90 o -60 o latitude Cool summers, cold year-round Dry
TEMPERATE 60 o -30 o latitude True Seasons Variety of climate patterns Moderate precipitation (rain/snow)
TROPICAL 30 o - equator No winter, warm year-round High temp, rainfall, humidity
Climate Types by Brainpop.What is climate?.Where are tropical climates most likely to be?.What does arid mean?
What Factors Affect Weather & Climate? The Sun The Sun The Water Cycle The Water Cycle The Atmosphere The Atmosphere The Ocean The Ocean
How Does the Sun Affect Weather? It warms the atmosphere & oceans It creates climate zones It keeps the water cycle going It affects weather patterns
The Water Cycle All the water on the planet is recycled in this manner!
Parts of the Cycle Evaporation EvaporationWater going from a liquid to a gas (gains energy from the sun)
Parts of the Cycle *Transpirationevaporation of water from/out of plants. Locate this on the diagram! transpiration
Parts of the Cycle Condensation CondensationWater going from a gas to a liquid (cools or loses energy) When this happens in the atmosphere, CLOUDS form.
Clouds by Brainpop
Parts of the Cycle Precipitationwhen water falls out the atmosphere. Forms when the water droplets in clouds become too heavy to stay up.
Precipitation Liquid water = rain Frozen water = snow or sleet or hail Rain Clip
The Water Cycle Water Cycle by Brainpop
Water Cycle Advanced by Brainpop
The Water Cycle by Brainpop 1)What process must happen for clouds to form? 2)What is collection? 3)Name one way to conserve water.
How does the atmosphere affect weather? The atmosphere is a mixture of gases that surrounds the Earth Has five different layers; each has different properties Well label them in just a minute… Air Temperature and Pressure change with altitude Weather occurs in the layer closest to Earth (troposphere)
Troposphere Stratosphere Mesosphere Ionosphere Exosphere Thermosphere Write in the labels! Ozone layer
Exosphere - the outermost layer of the Earth's atmosphere, where atmospheric pressure and temperature are low. Ionosphere - the atmospheric layer between the mesosphere and the exosphere; it is part of the thermosphere. Mesosphere - the atmospheric layer between the stratosphere and the ionosphere. Stratosphere - the atmospheric layer between the troposphere and the mesosphere. The stratosphere is characterized by a slight temperature increase with altitude and by the absence of clouds. Thermosphere - the layer of the atmosphere located above part of the ionosphere (starting at the coldest part of the atmosphere) and below outer space; it consists of the exosphere and part of the ionosphere. Troposphere - the lowest layer of the Earth's atmosphere. The weather and clouds occur in the troposphere.
Earths Atmsophere by Brainpop. What is ozone?. What layer of the atmosphere does weather occur in?. What 2 gases compose the most of Earths Atmosphere?
Air Masses = body of air with a certain temperature and moisture level Can be warm or cold Can contain a lot of moisture or not a lot of moisture
Fronts = places where air masses meet 4 Types: Warm, Cold, Occluded, Stationary Each kind can bring different kinds of weather
Occluded Front:Stationary Front:
Science Saurus 221/222 & Reading a Weather Map Worksheet
How does Air Pressure affect weather? How much the earths atmosphere is pressing down on us Measured with a BAROMETER If it CHANGES, then new weather is on the way: Falling Air Pressure = stormy weather coming Rising Air Pressure = fair weather coming Steady Air Pressure = no change is coming
Winds Winds = created from differences in air pressure Moves from areas of HIGH to LOW pressure Greater the difference in pressure, the FASTER the wind blows Measured with wind vanes and anemometers or you can estimate with the Beaufort Wind Scale ScienceSaurus 224/225
Beaufort Wind Scale
Global Winds Thousands of kilometers long; can cause weather to move in different directions Jet stream, prevailing westerlies, doldrums, horse latitudes, trade winds Big Winds Blowin Worksheet & Science Saurus Section 217
Global Winds Caused by the temperature difference in different regions Hot Tropical Regionscauses air to rise Cold polar Regionscauses air to sink
Global Winds Also affected by Earths Spin Coriolis Effect = causes winds to curve to the right in the N. Hemisphere; to the left in the S. Hemisphere
Big Winds Blowin Worksheet
Winds by Brainpop. What does warm air do?. What do you call winds that blow all the time in the same part of the world?. What are jet streams?
Relative Humidity moisture Measure of the amount of moisture in the air compared to what the air could hold How full of water the air is Expressed as % saturated 100% relative humidity = saturated air Relative Humidity Test Applet http://itg1.meteor.wisc.edu/wxwise/relhum/rhac.html
Relative Humidity Controlled by temperature Warm 1. Warm air holds more moisture than cool air (more space for water vapor between air molecules) warms decreases 2. As air warms, relative humidity decreases cools increases 3. As air cools, relative humidity increases
Dew Point =Temperature at which the air is saturated (100% relative humidity) Several events can occur when the dew point temp. is reached: 1. If dew point temp. is above freezing: liquid a. water vapor condenses as liquid b. dew will form on surfaces
Dew Point c. cloud droplets will form in air 2. If dew point temp. is below freezing: a. water vapor condenses as a solid b. frost on surfaces c. snow (or hail) in the air
Humidity by Brainpop. What single factor controls humidity?. What temperature air can hold the most water molecules?. What causes water to evaporate into the atmosphere?
RainbowsRainbowsRainbowsRainbows sunshine Caused by sunshine on raindrops White light (all colors) is refracted (bent) into colors as it enters and exits the drop behind To see a rainbow you must have the sun behind you and raindrops in the air Diagram:
Rainbow by Brainpop
How does the Ocean affect weather? Ocean currents affect the temperature of the land they pass by Cold ocean currents = cooling effect Warm ocean currents = warming effect Temperature changes affect pressure – which then creates WINDS Winds blow this cooling or warming effect over the land http://earth.rice.edu/MTPE/hydro/hydrosphere/topics/Ocean_Atm_Circ_ElNi no.mov
Science Saurus Sections 203-204-205-206
Advanced Weather by Brainpop Violent Weather
Thunderstorms Requires a mature cumulonimbus cloud Signs Sudden reversal of wind direction Noticeable increase in wind speed Sudden drop in temperature
Possible weather: a. heavy rains (flash floods) b. lightning (forest fires) c. thunder (frightens animals) d. hail (crop damage) e. tornadoes f. strong, gusty winds Thunderstorm by Brainpop Thunderstorms
Safety Rules Stay indoors Prepare for lightning, strong winds Listen on radio/TV for tornado watch/warning Thunderstorms dont last long
Lightning Storm Cumulonimbus cloud becomes electrically charged and ground below has opposite charge
current Lightning stroke: flow of current thru air (a poor conductor) from the – to the + cloud Lightning can flow from cloud to ground, cloud to cloud, and from ground to cloud glowing Bright light is caused by glowing air molecules heated by the current resistance Lightning follows the path of least resistance (easiest way to positive) easy Lightning rod offers lightning an easy, safe path to the ground (+)
Thunder Thunder is the shock wave caused by the explosive expansion of heated air 1100 Sound travels @ about 1100 ft/sec in air 5,280 ft in one mile seconds Distance from you to lightning = number of seconds between seeing the flash and hearing the thunder divided by 5. (5,280 ft / 1100 ft/sec = 5 seconds)
Types of Lightning Streak or bolt Single or branched lines of light Common in Puget Sound area
Sheet a. shapeless flash over wide area b. is cloud-to-cloud bolt hidden by the clouds c. common in Puget Sound area
Other types of lightning a. heat, ribbon, beaded (types of bolt) b. ball (only other shape lightning can have)
Safety rules for lightning storms Stay indoors Stay away from anything that conducts electricity (stove, sink, telephone, TV) Get out of the water and off of small boats Stay away from open doors, windows, fireplaces Stay in your car (very safe place to be) Dont stand under lone trees or in open places Avoid hilltops If your hair stands on end, or your skin tingles, drop to the ground but try to keep as little contact with the ground as possible
Lightning Strikes (17 minutes) Stories of people hit by lightning
Tornado Tornado (a.k.a twister, cyclone) Counterclockwise column of rotating air extending from cumulonimbus cloud Per square foot, is the most destructive atmospheric event Rated by wind speed (F1 to F5) Tornado season = April, May, June Tornadoes that form over water are called waterspouts
Behavior of a tornado is unpredictable Typical tornado will: 1. Occur between 3-7 pm 2. Travel 4 miles 3. Be 300-400 m wide 4. Travel 25-40 mi/hour 5. Have wind speeds up to 300 mi/hr 6. Produce extremely low pressure 7. Be dark due to debris picked up Tornado by Brainpop
Safety Rules Rule #1: Take immediate action! Move away from tornados path Tornados path Move away at a right angle
Lie flat in nearest ditch, etc. At home a. open windows, doors b. seek shelter in basement or under heavy table in middle of house On the trail of a tornado
Tropical Cyclone Nicknames 1. Atlantic: hurricane 2. SE Asia, Japan: typhoon 3. Australia: willy-willy 4. Indian Ocean: cyclone
Tropical Cyclone Rated by wind speed (category 1 to 5) Starts and grows over warm ocean water Composed of bands of thunderstorms spiraling counterclockwise around a low pressure center
Characteristics Several hundred miles wide Last many days (even weeks) Winds from 74-200 mi/hr Contains an eye Small region of low pressure Surrounded by highest winds Calm, peaceful, sunny weather Last for about 1 hour as hurricane passes by Hurricances by Brainpop
Safety Rules Prepare for high winds Prepare for flooding (greatest source of damage) Up to 20 in. of rain Flooding by coastal water 3. Prepare for thunderstorms 4. Have on hand stored food, water, blankets, candles, matches, radio, etc. 5. Seek shelter HurricanesHurricanes Clip