Weather and Climate 7th Grade ESS 7.2 and LS 7.2

Weather and Climate 7th Grade ESS 7.2 and LS 7.21EngagementWhy is weather important in Ohio?

Is climate important in Ohio?

Spend 2 minutes sharing your thoughts with 1 partner.

2Climate is what you expect; Weather is what you get. ~Mark Twain

Weather is what you wear each day, and climate is whats in your closet!

3Show video http://video.nationalgeographic.com/video/science/earth-sci/climate-weather-sci/

4Vocabulary TermsWeatherRadiationAbsorptionConvection CurrentsMeteorologyAtmosphereForecastClimate

Air pressureWater CycleFrontsHumidityTemperaturePrecipitation5Recognize that the Sun provides the energy that drives convection within the atmosphere and oceans, producing winds and ocean currents;How does the Suns energy drive our weather and climate systems?

6Think-Pair-ShareThe Sun warms the Earths atmosphere primarily because

The sunlight is absorbed by the atmosphere.The sunlight and heat from the Sun are absorbed by the atmosphere.The sunlight is absorbed by the land and oceans.The sunlight and heat from the Sun are absorbed by the land and oceans.7Earths Radiation Budget

From http://ceres.larc.nasa.gov/ceres_brochure.php?page=2 Visible LightFrom NASA CERES brochureThe sun's radiant energy is the fuel that drives Earth's climate engine. As shown in the figure, the Earth-atmosphere system constantly tries to maintain a balance between the energy that reaches the Earth from the sun and the energy that flows from Earth back out to space. Energy received from the sun is mostly in the visible (or shortwave) part of the electromagnetic spectrum. About 30% of the solar energy that comes to Earth is reflected back to space. The ratio of reflected-to-incoming energy is called "albedo" from the Latin word meaning whiteness. The solar radiation absorbed by the Earth causes the planet to heat up until it is radiating (or emitting) as much energy back into space as it absorbs from the sun. The Earth's thermal emitted radiation is mostly in the infrared (or longwave) part of the spectrum. The balance between incoming and outgoing energy is called the Earth's radiation budget.

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The solar radiation heats the surface of the Earth. Heat is transferred to air molecules that come in contact with the ground or ocean.Ask students how the ground transfers heat to the air before clicking the animation.Click to make the molecules appear.Ask students what happens when the molecules touch the ground? (heat is transferred, molecules gain energy, molecule move faster)Ask students what happens when the molecules become heated? (they rise)What type of energy does this show? (convection)

(Teacher Notes the vocabulary is a review from previous years but you may need to go over it multiple times if they dont seem to remember.) Reviewing: slides from http://greenslime.info/notes.html

As the Warmer Air RisesCooler air is pulled in from other placesConvectionCooler air is pulled in from other placesRead through parts of the slide as they appear.Allow time for students to answer the question.

Reviewing: slides from http://greenslime.info/notes.htmlWhere else do we see convection?As long as there is gravity, convection occurs any time there is a fluid with heating and cooling; i.e., convection in the atmosphere that causes wind, convection in the ocean that causes ocean currents, & convection in the mantle. It even happens when you boil water in a pot on the stoveas the pan heats, it heats the water touching itthe warmer water rises to be replaced by the cooler, more dense water sinking.11

LowPressureHighPressureWINDConvection current the transfer of heat energy through a fluid due to gravityWhy does the warm air rise? it is less dense (kids should remember this from the engage/explore activities)The rising air leaves room for more air to move in from other locations (click)As the air rises it cools and spreads out along the top of the troposphere (click)Cooler air is more dense and sinks creating an area of high pressure (click)The air move from the area of high pressure to the area of low pressureWe call this wind (click)This cycle of air is called a convection current (click)Allow students time to write the definition, the next click will make it disappear. (click)The part of a convection current that moves across the surface of the earth is called (click) wind.The rising air creates an area of low pressure (click) Low pressure means there are fewer air molecules per unit volume (less density).The more dense sinking air creates an area of high pressure (click). High pressure means there are more air molecules per unit volume (more density)

***NOTE: a FLUID is not a LIQUID but a LIQUID is a FLUID. Fluid is matter that flows. Liquid is a state of matter that has volume but no definite shape.

Reviewing: slides from http://greenslime.info/notes.html

Image from http://pubs.usgs.gov/gip/deserts/atmosphere/ 13Think, Pair, ShareHow does a convection current work?

Why do we have wind?CONVECTION CURRENT: Students should explain/diagram what they just learned.WIND: Since the Earth is heated unevenly, we have areas of high and low pressure all over because we also have gravity. The air is going to flow from areas of high pressure to areas of low pressurethis flow of air is what we call WIND!14How does the Suns energy drive ocean currents?

Image from Windows to the UniverseInformation at http://www.windows2universe.org/earth/Water/ocean_currents.html

15Visuals of Currents and Windshttp://www.nasa.gov/topics/earth/features/perpetual-ocean.html#.Uj9caNKsiSo

http://www.classzone.com/books/earth_science/terc/content/visualizations/es2401/es2401page01.cfm?chapter_no=visualization 16The WindResult of uneven heating of the Earths surfacecauses differences in air pressure to develop (cold air near the poles, warm air near the Equator)Molecules always move from areas of high pressure to areas of low pressure

Image courtesy of NASA.Student notesAsk students if they like being under a lot of pressure (think stress). Explain that the air doesnt like high pressure because it doesnt like being pushed down into the ground so it flows to a less dense area.

ANALOGY:Think of a hill of dirt next to a hole thats the dirt came from. Call the hill high (more dirt) pressure and the hole since its missing the dirt low pressure. Place a hose on the hill and turn on the water slowlywhat does the water do? It FLOWS from the Hill (AREA OF HIGH PRESSURE) to the Hole (AREA OF LOW PRESSURE).

Leading edge of an air mass

4 kinds of fronts:Cold frontWarm frontStationary frontOccluded frontfront boundaryFrontal Boundaries18Cold Front: mass of cold air moving into area of warmer airWarm Front: mass of warm air moving into area of cooler airStationary Front: masses of cold & warm air meet from opposite directions and stop movingOccluded Front: mass of cold air overtakes mass of warm air moving in same directionWeather Terms/Symbols

Emphasize shape and color of each symbolMore information about fronts can be found on the NOAA web site: Surface Fronts and Boundaries [http://www.hpc.ncep.noaa.gov/html/fntcodes2.shtml]19Cold Frontmass of cold air moving into area of warmer aircold air forces warm air up & over the cold air; often creating stormsImage courtesy of http://www.srh.noaa.gov/crp/?n=education-airmasses

Most (not all and not always) severe weather is associated with a cold front entering the area.Note: the leading edge of the cold air mass is the FRONT of the air masstherefore, the COLD FRONT (keep reviewing what an air mass is (mass of air with similar temperature and humidity throughout)More information: http://apollo.lsc.vsc.edu/classes/met130/notes/chapter11/cf_xsect.html AND http://www.physicalgeography.net/fundamentals/7r.html (PhysicalGeography.net)Aslo a basic animation: warm air ahead of front is lifted up and over 20Warm Frontmass of warm air moving into area of cooler airAs front enters, rain showers, then light rain, then clearing and warmerImage courtesy of http://www.srh.noaa.gov/crp/?n=education-airmasses

More information: http://www.physicalgeography.net/fundamentals/7r.html (PhysicalGeography.net)21Stationary Frontsair masses are not moving against each other forms when a cold front or warm front stops movingmay stay put for daysoften cloudy with rain or snow

Image from http://www.windows2universe.org/earth/Atmosphere/tstorm/stat_front.html 22Occluded Frontsforms when a cold air mass overtakes a warm frontLight to moderate rain before and duringClearing and cooler afterImage courtesy of the http://www.windows2universe.org/earth/Atmosphere/tstorm/occl_front.html

23OceansShow moviehttp://svs.gsfc.nasa.gov/vis/a010000/a011000/a011056/The_OCEAN.mov

24Where does weather take place?The Earth has 4 layers within its atmosphere. Almost all of the weather that occurs on Earth takes place in the lowest layer of the atmosphere known as the troposphere. 25

26Lower Layers of AtmosphereTroposphere: lowest layer extends up to 10km; contains 99% of the water vapor and 75% of the atmospheric gases.The troposphere is the first layer above the surface and contains most clouds (we live here).Most weather occurs in this layer. Most of the layers heat is from Earth.Temperature cools about 6.5 degrees Celsius per kilometer of altitude. 27Lower Layers of AtmosphereStratosphere directly above troposphere, extending from 10 km to about 50 km above Earths surfacePortion of the upper layer contains high levels of a gas called ozone. The ozone layer absorbs harmful rays from the Sun.Many jet aircrafts fly in the stratosphere because it is very stable.

28Upper Layers of AtmosphereMesosphere extends from the top of the stratosphere to about 85 km above EarthColdest layer. Meteors burn up in the mesosphere.

*Ionosphere* is found here layer of charged particlesThe ionosphere and exosphere is housed within the Thermosphere. 29Upper Layers of AtmosphereThermosphere thickest atmospheric layer found between 85 km and 500 km above Earths surfaceThe thermosphere is a layer with auroras, known for its high temperatures. Warms as it filters out X-rays and gamma rays from the Sun

*Ionosphere* here, too help carry radio waves.30Upper Layers of Atmosphere*Exosphere* The upper part of the Thermosphere that merges into space. The exosphere is the upper limit of our atmosphere and is extremely thin. Outer layer where space shuttle orbits.31

World Biomes33What is a Biome?Scientists have developed the term Biome to describe areas on the earth with similar climate, plants, and animals. The plants and animals that live in a specific biome are physically well adapted for that area. Plants and animals that live in a specific biome share similar characteristics with other plants and animals in that biome throughout the world. The types of biomes that will be explored during this exercise include: Tundra, Deserts, Grasslands, Taiga, Temperate Forests, and Rainforests

Tundra

Rainforest

Grassland

Taiga

Temperate Forest

DesertClick on the Biome you wish to exploreBiome ActivityWorld BiomesGo to Specific Activity QuestionEXIT

Group Project TundraDesertsGrasslandsTaigaTemperate ForestsRainforests

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