Weather and Climate 7th Grade ESS 7.2 and LS 7.2

Engagement Why is weather important in Ohio? Is climate important in Ohio? Spend 2 minutes sharing your thoughts with 1 partner.

“Climate is what you expect; Weather is what you get “Climate is what you expect; Weather is what you get.” ~Mark Twain “Weather is what you wear each day, and climate is what’s in your closet!”

Show video http://video. nationalgeographic

Vocabulary Terms Weather Radiation Absorption Meteorology Atmosphere Convection Currents Meteorology Atmosphere Forecast Climate Air pressure Water Cycle Fronts Humidity Temperature Precipitation

How does the Sun’s energy drive our weather and climate systems? Recognize that the Sun provides the energy that drives convection within the atmosphere and oceans, producing winds and ocean currents; How does the Sun’s energy drive our weather and climate systems?

Think-Pair-Share The Sun warms the Earth’s 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.

Earth’s Radiation Budget Visible Light From NASA CERES brochure The 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. From http://ceres.larc.nasa.gov/ceres_brochure.php?page=2

The solar radiation heats the surface of the Earth. 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 don’t seem to remember.) Reviewing: slides from http://greenslime.info/notes.html Heat is transferred to air molecules that come in contact with the ground or ocean.

Convection As the Warmer Air Rises… Cooler air is pulled in from other places Cooler air is pulled in from other places Read through parts of the slide as they appear. Allow time for students to answer the question. Reviewing: slides from http://greenslime.info/notes.html Convection

Where 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 stove…as the pan heats, it heats the water touching it…the warmer water rises to be replaced by the cooler, more dense water sinking.

Low Pressure WIND High Pressure Convection current – the transfer of heat energy through a fluid due to gravity Low Pressure WIND Why 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 pressure…We 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 High Pressure

Image from http://pubs.usgs.gov/gip/deserts/atmosphere/

How does a convection current work? Why do we have wind? Think, Pair, Share… How 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 pressure…this flow of air is what we call WIND!

How does the Sun’s energy drive ocean currents? Information at http://www.windows2universe.org/earth/Water/ocean_currents.html Image from Windows to the Universe

Visuals of Currents and Winds http://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

The Wind Result of uneven heating of the Earth’s surface causes 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 notes Ask students if they like being under a lot of pressure (think stress). Explain that the air doesn’t like high pressure because it doesn’t 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 that’s 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 slowly…what does the water do? It FLOWS from the Hill (AREA OF HIGH PRESSURE) to the Hole (AREA OF LOW PRESSURE).

Frontal Boundaries Leading edge of an air mass 4 kinds of fronts: Cold front Warm front Stationary front Occluded front front boundary

Weather Terms/Symbols Cold Front: mass of cold air moving into area of warmer air Warm Front: mass of warm air moving into area of cooler air Stationary Front: masses of cold & warm air meet from opposite directions and stop moving Occluded Front: mass of cold air overtakes mass of warm air moving in same direction Emphasize shape and color of each symbol More information about fronts can be found on the NOAA web site: Surface Fronts and Boundaries [http://www.hpc.ncep.noaa.gov/html/fntcodes2.shtml]

Image courtesy of http://www.srh.noaa.gov/crp/?n=education-airmasses Cold Front mass of cold air moving into area of warmer air cold air forces warm air up & over the cold air; often creating storms 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 mass…therefore, 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 Image courtesy of http://www.srh.noaa.gov/crp/?n=education-airmasses

Image courtesy of http://www.srh.noaa.gov/crp/?n=education-airmasses Warm Front mass of warm air moving into area of cooler air As front enters, rain showers, then light rain, then clearing and warmer More information: http://www.physicalgeography.net/fundamentals/7r.html (PhysicalGeography.net) Image courtesy of http://www.srh.noaa.gov/crp/?n=education-airmasses

Stationary Fronts air masses are not moving against each other forms when a cold front or warm front stops moving may stay put for days often cloudy with rain or snow Image from http://www.windows2universe.org/earth/Atmosphere/tstorm/stat_front.html

Occluded Fronts forms when a cold air mass overtakes a warm front Light to moderate rain before and during Clearing and cooler after Image courtesy of the http://www.windows2universe.org/earth/Atmosphere/tstorm/occl_front.html

Oceans Show movie http://svs.gsfc.nasa.gov/vis/a010000/a011000/a011056/The_OCEAN.mov

Where 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.

Lower Layers of Atmosphere Troposphere: 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 layer’s heat is from Earth. Temperature cools about 6.5 degrees Celsius per kilometer of altitude.

Lower Layers of Atmosphere Stratosphere – directly above troposphere, extending from 10 km to about 50 km above Earth’s surface Portion 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.

Upper Layers of Atmosphere Mesosphere – extends from the top of the stratosphere to about 85 km above Earth Coldest layer. Meteors burn up in the mesosphere. *Ionosphere* is found here – layer of charged particles The ionosphere and exosphere is housed within the Thermosphere.

Upper Layers of Atmosphere Thermosphere – thickest atmospheric layer found between 85 km and 500 km above Earth’s surface The 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.

Upper 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.

World Biomes

What 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

Click on the Biome you wish to explore World Biomes EXIT Click on the Biome you wish to explore Tundra Desert Temperate Forest Taiga Rainforest Grassland Biome Activity Go to Specific Activity Question

Tundra Deserts Grasslands Taiga Temperate Forests Rainforests Group Project Tundra Deserts Grasslands Taiga Temperate Forests Rainforests