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The study of atmospheric phenomena What is Meteorology? The study of atmospheric phenomena Greek root word meteoros.. High in the air

Examples of meteors…

Anything high in the sky Raindrops Rainbows Dust Snowflakes Fog Lighting

Atmosphere phenomena are classified as types of meteors Hydrometeors: cloud droplets & precipitation (rain, snow & sleet) Lithometeors: suspended particles (smoke, dust & haze) Electrometers: signs of electricity (thunder & lighting)

Variations of Atmosphere Phenomena Weather: short term variations in atmospheric phenomena Climate: long term average of variations in weather for a particular area (over 30 years)

4 causes of weather The uneven solar heating of the earth’s surface Transfer of thermal energy (R,C,C) Water phase change (E,C,P) releasing latent heat Air masses traveling & colliding

Air Masses Air Mass: a large body of air that has the same characteristics (Temperature & Moisture) as its source region Source Region: area of earth’s surface that effects air mass formation Air Mass Modification: As it moves over land or water with different characteristics, it transfers thermal energy and/or moisture

Air Mass Classification Moisture: influenced by surface designated m for maritime (wet) & c for continental (dry) Temperature: influenced by latitude High Latitude = Cold & Low Latitude = Warm A (arctic), P (polar) and T (tropical)

Mid latitudes are zones of clashing air masses = stormy

Air Masses Effecting North America Much of the weather in North America, especially weather east of the Rocky Mountains, is influenced by continental polar (cP) & maritime tropical (mT) air masses.

HOMEWORK Review Notes Quiz Tomorrow Read Text p 312 – 316 Ch 12 Study Guide Sheet due Friday 4/3

What degree latitude is the Tropic of Cancer? QUIZ 1. Define Weather 2. Define Climate 3. Name one cause of weather 4. Name the two classifications of air masses 5. (m) Maritime air mass has what characteristic? BONUS What degree latitude is the Tropic of Cancer?

Day & Night Across the Earth Science News Day & Night Across the Earth Sun and Moon Data for CHICAGO IL

Good Good Good Good Good Good Good

Continental polar (cP) AIR MASSES & WEATHER Continental polar (cP) From northern Canada and interior of Alaska Winter very cold, dry Summer cool, dry Responsible for lake-effect snows Mass crosses the Great Lakes

AIR MASSES & WEATHER Maritime polar (mP) From North (P)acific & (A)tlantic Oceans Winter (P) mild, humid (A) cold, humid Summer (P) mild, humid (A) cold, humid Influence in the northeastern & western United States causing cold temperatures and snow

Continental tropical (cT) AIR MASSES & WEATHER Continental tropical (cT) From Southwest and Mexico Winter warm, dry Summer hot, dry

Maritime tropical (mT) AIR MASSES & WEATHER Maritime tropical (mT) From the Gulf of Mexico and the Atlantic Ocean Winter warm, humid Summer hot, humid Eastern USA Usually unstable!

What is WIND? The horizontal motion of air across Earth’s surface; movement produced by differences in air pressure from an area of high pressure (warm air) to an area of low pressure (cool air)

GLOBAL WINDS

Global Winds The atmosphere balances differences of unequal heating by acting as a giant heat-transfer system. This system moves warm air toward high latitudes and cool air toward the equator

GLOBAL Direction of WIND Makes no sense without caption in book

3 WIND SYSTEMS “ZONES” Polar easterlies 60 DEGREES – POLES N & S LATITUDES Dense cold air sinking from the polar high toward the sub polar low. These winds are not constant like the trade winds.

Westerlies 30 – 60 DEGREES N & S LATITUDES Dominant and steady surface wind moving west-to-east towards the POLES. Move much of the weather across USA & Canada.

Trade winds 30 degrees N – 30 degrees S LATITUDES Two belts of winds, air in this region sinks, warms and moves toward the equator in an easterly direction.

Boundaries of Wind Systems JET STREAM: A narrow band of fast moving wind that varies with seasons Result of the difference between air masses (Temperature & Pressure) at the wind zone boundaries.

Separate polar easterlies from prevailing westerlies 2 Types of JETSTREAMS Major POLAR JET STREAM Separate polar easterlies from prevailing westerlies Move East to West Latitudes 40 N- 60 N & 40 S-60 S

Separate trade winds from westerlies Minor Subtropical Separate trade winds from westerlies Latitudes 20 N – 30 N & 20 S – 30 S

Why are the winds systems broken into zones?? Coriolis effect

HOMEWORK Review Notes Quiz Tomorrow Read Text p 318-323 Ch 12 Study Guide Sheet due Friday 4/3