Chapter 2 – Weather PatternsChapter 2 – Weather PatternsGuided NotesGuided Notes

Objective(s)Objective(s)::7.E.1.4 7.E.1.4

Predict weather conditions and patterns based Predict weather conditions and patterns based on information obtained from:on information obtained from:

• Weather data collected from direct observations and measurement (wind speed and direction, air temperature, humidity and air pressure)• Weather maps, satellites and radar• Cloud shapes and types and associated elevation

7.E.1.5 Explain the influence of convection, global winds and the jet stream on weather and

climatic conditions.

• Learner Objective(s):Learner Objective(s):

Students will understand that the Students will understand that the water cycle and atmospheric water cycle and atmospheric conditions are interconnected and conditions are interconnected and create the weather we see on Earth.create the weather we see on Earth.

Concept/Vocabulary Word Concept/Vocabulary Word Definition Definition • DepositionDeposition - The process of water vapor changing from - The process of water vapor changing from

a gas directly into a solid.a gas directly into a solid.• Dew PointDew Point - The temperature at which water vapor will - The temperature at which water vapor will

start to condense out of the air as liquid water. start to condense out of the air as liquid water. • EvaporationEvaporation - The process of a liquid changing into a - The process of a liquid changing into a

gasgas• FogFog - Clouds that form at the surface of the Earth. - Clouds that form at the surface of the Earth.• Ground WaterGround Water - Water that has infiltrated (sunk) into - Water that has infiltrated (sunk) into

the ground.the ground.• HydrosphereHydrosphere - All of the Earth's water that is cycling - All of the Earth's water that is cycling

within the water cycle.within the water cycle.• MeteorologistMeteorologist - A scientist who studies the - A scientist who studies the

atmosphere, weather and climateatmosphere, weather and climate• PrecipitationPrecipitation - Any type of liquid or solid water that - Any type of liquid or solid water that

falls to Earth's surface.falls to Earth's surface.  

• Run Off Run Off - Water that flows across the surface of - Water that flows across the surface of the Earth.the Earth.

• SublimationSublimation - The process of water changing - The process of water changing from a solid directly into a gas.from a solid directly into a gas.

• TranspirationTranspiration - The process of water - The process of water evaporating from the leaves of plants during evaporating from the leaves of plants during photosynthesis.photosynthesis.

• Water CycleWater Cycle - The repeating processes that - The repeating processes that move water in different forms between Earth's move water in different forms between Earth's surface and the atmospheresurface and the atmosphere

• Water vaporWater vapor - Water in the atmosphere that is - Water in the atmosphere that is in the form of a gas.in the form of a gas.

• WeatherWeather - The condition of Earth's atmosphere - The condition of Earth's atmosphere at a particular time and placeat a particular time and place

• Weather patternsWeather patterns - Weather that repeats itself - Weather that repeats itself in a predictable way. in a predictable way.

I.I. SECTION 2.1 – The atmosphere’s SECTION 2.1 – The atmosphere’s air pressure changesair pressure changesA.A. Air exerts pressureAir exerts pressure

• Exploring air pressure – What does air do to the egg? Exploring air pressure – What does air do to the egg?

http://www.youtube.com/watch?v=2VHneRg0mhI&list=PLMWvLl-qJ8maQ15p1kZBooG1L1AoFCz6_&feature=plcp

• Air Air pushespushes or exerts a or exerts a forceforce• Air pressure – Air pressure – is the force of air molecules pushing on an areais the force of air molecules pushing on an area• As you move As you move upwardupward in the atmosphere, air pressure in the atmosphere, air pressure decreasesdecreases• The greater the The greater the forceforce, the higher the , the higher the air pressureair pressure• Air pressure pushes in Air pressure pushes in allall directions directions  

B.B. Pressure and Air motionPressure and Air motion• Air pressure Air pressure decreasesdecreases as you move to as you move to higherhigher altitude altitude

• Air moves from areas of Air moves from areas of higher pressurehigher pressure to areas of to areas of lower lower pressurepressure

C. Barometers and Air PressureBarometer – is any instrument that measures air pressure

III. III. SECTION 2.2SECTION 2.2. . – The – The atmosphere has wind atmosphere has wind patternspatterns• Wind blows from areas of Wind blows from areas of

high pressure toward areas of low high pressure toward areas of low pressure. Earth's rotation causes pressure. Earth's rotation causes long distance winds to curve.long distance winds to curve.

area of high

pressure

area of low pressure

A.A. Uneven heating causes air to moveUneven heating causes air to move

•Weather – Weather – is the condition of Earth’s is the condition of Earth’s atmosphere at a particular time and placeatmosphere at a particular time and place

•Wind – Wind – is air that moves horizontally, or is air that moves horizontally, or parallel to the groundparallel to the ground

•Uneven heating causes Uneven heating causes pressure differencespressure differences which set air in motionwhich set air in motion

•Over a short distance, wind moves directly Over a short distance, wind moves directly from higher pressure toward lower pressurefrom higher pressure toward lower pressure

•Global winds - Global winds - travel thousands of kilometers travel thousands of kilometers in steady patterns and last for weeksin steady patterns and last for weeks

•Uneven heating between the Uneven heating between the equatorequator and the and the northnorth and and southsouth poles cause global winds poles cause global winds

B.B. Earth’s rotation affects wind directionEarth’s rotation affects wind direction

•Coriolis effect – Coriolis effect – influence on Earth’s rotationinfluence on Earth’s rotation•Global windsGlobal winds curve as Earth turns beneath curve as Earth turns beneath

themthem• In the In the NorthernNorthern Hemisphere, winds curve to Hemisphere, winds curve to

the right in the direction of motionthe right in the direction of motion• In the In the SouthernSouthern Hemisphere, winds curve to Hemisphere, winds curve to

the left in the direction of motionthe left in the direction of motion• The Coriolis effect is noticeable only The Coriolis effect is noticeable only

for winds that travel for winds that travel longlong distances distances http://www.youtube.com/watch?v=uBqohRu2RRk&list=PLMWvLl-qJ8maUvrKjCzRx27pJ9NnKCcWG&feature=mh_lolz

• Investigate: How does Earth’s rotation affect wind?  Investigate: How does Earth’s rotation affect wind?  C.C. Bands of calm air separate global wind Bands of calm air separate global wind

beltsbelts•Calm regions – Calm regions – doldrums and horse latitudesdoldrums and horse latitudes

– Doldrums – Doldrums – are a low-pressure zone near the equatorare a low-pressure zone near the equator– Horse latitudes – Horse latitudes – are high-pressure zones located about 30 are high-pressure zones located about 30

degrees north and 30 degrees south of the equator degrees north and 30 degrees south of the equator •Wind belts – Wind belts – trade winds, westerlies, and easterlies trade winds, westerlies, and easterlies

– Trade winds – Trade winds – blow from east, moving from the horse blow from east, moving from the horse latitudes toward the equatorlatitudes toward the equator

– Westerlies – Westerlies – blow from the west, moving from the horse blow from the west, moving from the horse latitudes toward the equator. They bring storms across latitudes toward the equator. They bring storms across much of the United Statesmuch of the United States

– Easterlies – Easterlies – blow from the east, moving from the polar blow from the east, moving from the polar regions toward the mid-latitudes. Stormy weather often regions toward the mid-latitudes. Stormy weather often occurs when the cold air of the easterlies meet the warmer occurs when the cold air of the easterlies meet the warmer air of the westerliesair of the westerlies

http://www.youtube.com/watch?v=I0C4QR0OEH0&list=PLMWvLl-qJ8mY36sh_gV7Ume-7kIPbtYIF&index=1&feature=plpp_video

D.D.Jet streams flow near the top of the Jet streams flow near the top of the tropospheretroposphere• Jet Streams – Jet Streams – usually flow in the usually flow in the

upper troposphere from west to upper troposphere from west to east for thousands of kilometerseast for thousands of kilometers

• Air often moves at speeds greater Air often moves at speeds greater than than 200 km/hr or 124 mph200 km/hr or 124 mph

• Forms when earth’s surface is Forms when earth’s surface is heated unevenlyheated unevenly

• Loop north and southLoop north and south• Each hemisphere usually has two Each hemisphere usually has two

jet streamsjet streams

E.E. Patterns of heating and cooling Patterns of heating and cooling cause local winds and monsoonscause local winds and monsoons•Local winds – Local winds – sea breezes and land breezessea breezes and land breezes

– Occur near shorelinesOccur near shorelines

Valley breezes

•Monsoons – Monsoons – winds that change directions winds that change directions with the seasonswith the seasons

– Caused by the different heating and cooling rates Caused by the different heating and cooling rates of land and seaof land and sea