WINDS

Responsible for triggering the initial movement of air.

SHIFT IN WIND DIRECTION DUE TO EARTH’S ROTATION CORIOLIS EFFECT SHIFT IN WIND DIRECTION DUE TO EARTH’S ROTATION

What happens if pressure is the same? No wind!

Earth’s Winds- due to uneven heating  pressure differences

Earth’s Winds- due to uneven heating  pressure differences Local Winds Sea breeze Land breeze

LOCAL WINDS Uneven heating of land vs water SEA BREEZE LAND BREEZE

Earth’s Winds- due to uneven heating  pressure differences Local Winds Seasonal Winds- over bigger region (ex-SE Asia) Sea breeze Land breeze monsoon

MONSOONS SEASONAL WINDS Similar to land and sea breeze bit occur over a wider area

Philippines Northeast Monsoon (cold and wet) Southwest Monsoon (dry)

Earth’s Winds- due to uneven heating  pressure differences Global/Planetary Winds Local Winds Seasonal Winds- over bigger region (ex-SE Asia) Sea breeze Land breeze monsoon

GLOBAL WINDS UNEQUAL HEATING equater vs. poles results in GLOBAL PATTERN OF AIR CIRCULATION

http://www.phschool.com/atschool/phsciexp/active_art/global_winds/index.html

On Surface Up In Atmosphere Jet Stream Earth’s Winds- due to uneven heating  pressure differences Up In Atmosphere Global/Planetary Winds Local Winds Seasonal Winds- over bigger region (ex-SE Asia) On Surface Trade Winds Polar Easterlies Prevailing Westerlies Sea breeze Land breeze monsoon

AIR MOVING BACK TO THE EQUATOR FORMING A BELT OF WARM, STEADY WINDS TRADE WINDS ON SURFACE: AIR MOVING BACK TO THE EQUATOR FORMING A BELT OF WARM, STEADY WINDS

PREVAILING WESTERLIES ON SURFACE 40-60 degrees Latitude (West to East) Strong Winds

COLD BUT WEAK WINDS EAST TO WEST POLAR EASTERLIES ON SURFACE COLD BUT WEAK WINDS EAST TO WEST

JET STREAMS “rivers of air" 180-350 Km/Hr (speed) IN ATMOSPHERE (ABOVE 12 KMS) 180-350 Km/Hr (speed)

On Surface Up In Atmosphere Jet Stream Earth’s Winds- due to uneven heating  pressure differences Up In Atmosphere Global/Planetary Winds Local Winds Seasonal Winds- over bigger region (ex-SE Asia) On Surface Trade Winds Polar Easterlies Prevailing Westerlies Sea breeze Land breeze NO Winds monsoon Horse Latitudes Doldrums

CALM/ NO WINDS AT EQUATOR (0 degrees latitude) DOLDRUMS ON SURFACE CALM/ NO WINDS AT EQUATOR (0 degrees latitude)

HORSE LATITUDES ON SURFACE 30 degrees North and South of Equator Warm air cools and sink; clear skies; winds are calm

http://www.phschool.com/atschool/phsciexp/active_art/global_winds/index.html

SHIFT IN WIND DIRECTION DUE TO EARTH’S ROTATION CORIOLIS EFFECT SHIFT IN WIND DIRECTION DUE TO EARTH’S ROTATION

As air moves from high to low pressure: in north, air deflected right/counterclockwise in the south, air is deflected left/clockwise

hurricanes/typhoons and tornadoes spin COUNTER-CLOCKWISE in NORTH

myth Flushing Toilets on the Equator Myth or Real: Toilets flushed in the northern hemisphere apparently spin to the right, in the southern hemisphere the water spins left -- this is supposedly caused by the Coriolis effect. And on the equator? It's a straight shot down. myth

BREAK TIME One big/important idea or fact Stand up Share with 3 people

So how do we get differences in pressure?

All factors making Low density & low pressure 1) temp: Warm air is less dense than cool air. REMEMBER THE OPPOSITE IS ALSO TRUE

UNEQUAL HEATING OF AIR DIFFERENCES IN DENSITY DIFFERENCE IN AIR PRESSURE EX) HOT temp (LESS dense)=>LOW P COLD temp (MORE dense)=>HIGH P

Air RISES HEAT LESS AIR PRESSURE Air molecules move faster and expand TEMPERATURE AND AIR PRESSURE LESS AIR PRESSURE Air RISES Air molecules move faster and expand HEAT less dense

All factors making Low density  low pressure 1) temp: Warm air is less dense than cool air. 2) humidity: Moist air is less dense than dry air. REMEMBER THE OPPOSITE IS ALSO TRUE

More water vapor means less air molecules Less dense = LOW AIR PRESSURE DRY AIR  more dense = HIGH AIR PRESSURE

All factors making Low density  low pressure 1) temp: Warm air is less dense than cool air. 2) humidity: Moist airis less dense than dry air. 3) elevation: Air at high altitudes (mountains) is less dense than air at lower altitudes. REMEMBER THE OPPOSITE IS ALSO TRUE

Air at high altitudes is more spread out = less dense than air at lower altitudes.

Measuring Air Pressure 2 Main Types of Barometer Air Pressure is measured by an instrument called Barometer Mercury Barometer Aneroid (spring)

Air pressure increases, column of mercury rises VIDEO: Why use mercury? Air pressure decreases, column of mercury drops Video (minute 2): http://www.youtube.com/watch?v=-gGBMCqBoSE&feature=related

Break time Think of one fact you learned from the video or what you found interesting Stand up Form groups based on the same idea

CLOUDS

TYPES OF CLOUDS

CLOUD FORMATION 1) WATER VAPOR (gas) rising (need heat to cause evaporation) 2) CONDENSATION NUCLEI (smoke, dust, pollution) 3)LOW TEMPERATURE for condensation (liquid) to occur

MOISTURE CONDENSES ON SMALL PARTICLES OF DUST/ SOLIDS IN THE AIR

CONDENSATION WATER VAPOR CHANGES INTO LIQUID (need cold temp)

TEMPERATURE AT WHICH water vapor CONDENSES DEW POINT TEMPERATURE AT WHICH water vapor CONDENSES

Source: http://www. vivoscuola. it/US/RSIGPP3202/umidita/lezioni/form

Air Pressure & Weather

Air RISES HEAT LESS AIR PRESSURE Air molecules move faster and expand TEMPERATURE AND AIR PRESSURE What happens when air rises? LESS AIR PRESSURE Air RISES Air molecules move faster and expand HEAT less dense

Low pressure generally means cloudy, rainy weather Warm air rises, clouds form

High pressure generally means fair weather Warm, moist air cannot rise =No clouds Layer of Air

Weather map High Pressure System: Indicates clear, calm conditions with reduced chance of precipitation. DRY and COLDER air Low pressure system: Increased cloudiness, winds, higher temperatures, and chance of precipitation.

Frost Formation Cold temperature causes water vapor (gas) to instantly freeze (solid) Skips liquid phase (never wet) Salt helped to make colder

When condensed water gathers into drops that are heavy enough, precipitation occurs Source: http://www.vivoscuola.it/US/RSIGPP3202/umidita/lezioni/form.htm

PRECIPITATION Cloud droplets Ice Snow

Hurricanes/Typhoons/Cyclones & Tornadoes

Hurricanes/typhoons/cyclones-what’s in a name? LOCATION, LOCATION, LOCATION http://spaceplace.nasa.gov/hurricanes/

HOW?

hurricanes/typhoons and tornadoes spin COUNTER-CLOCKWISE in NORTH

http://edition. cnn. com/2011/US/04/28/severe. weather/index. html http://edition.cnn.com/2011/US/04/28/severe.weather/index.html?hpt=T2 http://edition.cnn.com/2011/US/04/27/tornado.outbreak/index.html?hpt=T1 Experts: Severe weather across South could set tornado record

Including yesterday's storm, there have been a whopping 800 reports of tornadoes in April, easily surpassing April 2003's all-time record of 543 twisters. http://www.nytimes.com/interactive/2011/04/28/us/map-of-the-tornadoes-across-the-south.html

Song: http://www.youtube.com/watch?v=iOw6ONcKk4g http://news.yahoo.com/s/yblog_thelookout/20110428/ts_yblog_thelookout/watch-tuscaloosas-terrifying-tornado Yahoo video clips Tornadoes Song: http://www.youtube.com/watch?v=iOw6ONcKk4g