Weather TEKS 8.10 B Identify how global patterns of atmospheric movement influence local weather using weather maps that show high and low pressures and fronts. 8.10 C Identify the role of the oceans in the formation of weather systems such as hurricanes. Essential Questions How do global patterns of atmospheric movement influence local weather? How are weather maps used to identify global patterns of atmospheric movement? What is the role of oceans in the formation of weather systems?

Time for a Weather Report! http://www.youtube.com/watch?v=EK-9orptDhA

Fill out the before section of this comparison chart. Weather vs. Climate Which happens faster – a change in weather or a change in climate? What is weather? What is climate? Fill out the before section of this comparison chart. Warm-Up BEFORE AFTER WEATHER CLIMATE

This Week’s Forecast: What kind of weather do you expect this week? What do meteorologists predict about our local weather? http://www.weather.com/weather/5- day/Austin+TX+78757

If you said that weather and climate are different things, you’re right! The happenings in the atmosphere at a certain time. The meteorological conditions, including temperature, precipitation, and wind, that characteristically prevail in a particular region. A region of the earth having particular meteorological conditions: Ex: “lives in a cold climate.” Weather Climate

Meteorologists say climate is what you expect and weather is what you get. A perceptive middle school student said, “Climate helps you decide what clothes to buy, weather helps you decide what clothes to wear.”

In other words: Weather is what it is like outside right now. Climate is how the weather usually is in a particular area. For example, Austin is usually very hot in the summer, and we have mild winters. Climate change usually occurs over many years. Weather is what it is like outside right now. For example, a cold front came in this morning and now I want to stay inside. Weather can change in less than a minute! But what causes our weather to change?

Wind is simply the movement of air. Our weather depends a lot on the wind. Wind is simply the movement of air. What causes it and how does it impact our weather?

Explore Activity 1: The Movement of Air Masses Everyone stand very close together. Imagine 100 students from this school were tightly packed into this classroom with standing room only. If all doors and windows were closed, this room would be like a high pressure area. Would anyone want to come in to this area? Now, imagine that there is no one in the hall outside the classroom. The empty hall is like a low pressure area. Then, someone opens the door… Where would you want to go? Discuss different scenarios. What if there were people in the hall? How would that change your movement? There are actual classrooms in Uganda and Nepal. It looks like their desire to get an education is a strong enough force to keep them in a “high pressure” area.

We just modeled differences in air pressure. What is Air Pressure? Gravity pulls air molecules down toward the center of the Earth. Air pressure is the weight of the air resting on a given area of Earth’s surface.

Air Flows from High to Low Pressure! When a cool air mass sinks, it causes a high pressure area. Another air mass is not likely to move in because the pressure is already high…so weather in a high pressure area generally stays clear. When a warm air mass rises, it causes low pressure in the area left behind. Air from higher pressure areas will likely rush in and often cause cloudy and stormy weather!

Differences in Air Pressure Cause Wind! Because air is largely invisible to us, it is hard to picture the effects of air pressure. We can imagine molecules in the air are like people… they move from a high pressure area to a low pressure area! http://www.youtube.com/watch?v=ZcK3Avl4KgU Check out how differences in air pressure affect a balloon in a bottle… http://www.youtube.com/watch?v=Q3owA2hGMzE BrainPop: Wind! http://www.brainpop.com/science/weather/wind/preview.weml

Reflection… In your journal, revise your warm-up. Are climate and weather the same thing? Complete the AFTER section of your chart. Next, write a paragraph about the knowledge you gained today. Be specific. What did you learn? BEFORE AFTER WEATHER CLIMATE

Weather Vocabulary! Understanding the vocabulary is an important part of learning about weather. Fill in your graphic organizer!

High Pressure System In a high pressure system the atmospheric pressure of the air is higher than that of the air around it. (It’s more dense.) High atmospheric pressure systems are marked by an H on a weather map They will usually have clear weather. H

Low Pressure System In a low atmospheric pressure system, the atmospheric pressure of the air is lower than the air around it. The air is less dense. Low atmospheric pressure systems are symbolized by an L on a weather map. They mean storminess and precipitation. L

Front A boundary where two air masses meet that differ in temperature, pressure, and/or humidity.

Jet Stream A jet stream is a fast flowing, “river” of air. They form at the boundaries of connecting air masses that have big differences in temperature, such as of the polar region (VERY COLD AIR) and the warmer air to the south (VERY HOT AIR). Because of the Earth's rotation, jet streams flow west to east.

Measurements wind speed air pressure anemometer barometer [ORIGIN from Greek anemos ‘wind’] [ORIGIN from Greek baros ‘weight’]

Weather Map A map that shows weather conditions and can be used to predict weather.

Atmospheric Movement This is the large scale movement of air throughout the atmosphere. This movement is one of the ways heat is distributed all over our planet.

Global Pattern A global pattern is a trend seen throughout the world. Global winds and ocean currents are examples of global patterns. Climate has global patterns. These are systems that are important because they affect our entire planet.

Read the passage and complete the map of global wind patterns. Easterlies Westerlies Trade Winds Doldrums

Easterlies Westerlies Trade Winds Doldrums Trade Winds Westerlies Easterlies

Reflection… Write a paragraph about the knowledge you gained today and your experiences in a high pressure system. Be specific. What did you learn?

Can a Difference in Air Pressure Really Force Something to Move? Can air pressure alone force the egg into the bottle? In your science notebook, draw the demonstration set-up, and make a hypothesis about what will happen if your teacher heats the air inside the glass bottle.

What Happened to the Air & the Egg?

The burning piece of paper heats the molecules of air in the bottle and causes the molecules to move far away from each other. Some of the heated air molecules actually escape out past the egg that is resting on the mouth of the bottle. When the flame goes out, the molecules of air in the bottle cool down and move closer together. This is what scientists call a partial vacuum. Normally, the air outside the bottle would come rushing in to fill the bottle. However, that egg is in the way! The “push” or pressure of the air molecules outside the bottle is so great that it literally pushes the egg into the bottle! H L

How do we get the egg out again? Though there is always the simple mash it up and take it out in pieces option, there is a much more elegant and scientific strategy.  Hold the bottle upside down and blow into the bottle as hard as you can. Because you are blowing more air molecules into the bottle, you are increasing the air pressure inside the bottle! The egg should then be pushed out by the higher pressure air inside the bottle!

? Exit Ticket Look back in your journal about today’s lesson. Write either something you learned or a question you have on a post-it. Stick your post-it to the chart prepared for your class.

Warm-Up THINK, PAIR, SHARE: The movement of air in our atmosphere impacts life around the globe because _______________________________. Record your answer in your journal! Consider… Storm in Arizona: http://www.youtube.com/watch?v=DuMX9AM9BrE Flooding in Nebraska, Wild Fires in New Mexico, and Record Drought in Texas: http://www.youtube.com/watch?v=DbrT7nl7uVM

Weather can affect every aspect of life. The movement of air in the atmosphere greatly affect temperatures, how much precipitation we receive, and whether our homes and schools continue to stand or not. In Pictures: Horn of Africa in a record drought and famine Caledonia High School devastated by a tornado

We know that weather is… The happenings in the atmosphere at a certain time.

We also know that weather is greatly affected by wind…

What Causes Wind? One reason is… differences in pressure

What Causes Differences in Pressure? In general, pressure differences are caused by uneven heating of the earth’s surface by the sun. Low Pressure High Pressure

Why uneven? Remember that because of the shape and tilt of Earth, we don’t all get the same amount of the sun’s energy. Also, the earth’s surface is made of both land and water. Because the land and water are made of so many different materials with different properties, different areas absorb the sun’s radiation differently.

When you were in a high pressure situation, you wanted to move… so does the air! Warm air, which is less dense than cold air, rises. Then cool air moves in and replaces the rising warm air. This movement of air is what makes the wind blow. It is called a convection current.

Or look at it this way…

Wind blows from areas of This High Pressure Low Pressure Wind blows from areas of to areas of high pressure low pressure

(Describe at least 3 factors!) Reflection THINK, PAIR, SHARE: The movement of air in our atmosphere is caused by _______________________________. (Describe at least 3 factors!) Record your answer in your journal!

Because air flows from high to low pressure areas, we would expect…

However, global wind patterns look more like this: Why?

Earth’s Rotation & Inertia! The Coriolis Effect explains the patterns we see in the global winds (and ocean currents). Earth’s air and water have inertia. Because of this inertia as the Earth rotates, the air in the Northern hemisphere curves to the right and the air in the Southern hemisphere curves to the left.

Also, the Atmosphere is 3-D! Air does not just move N, S, E, and W along the surface, it also moves upward and downward in the atmosphere!

Is air rising or sinking at 30°N?

Is air rising or sinking at the equator?

Now, let’s look at patterns a little closer to home… using weather maps!