Partnerships Implementing Engineering Education Worcester Polytechnic Institute – Worcester Public Schools

Supported by: National Science Foundation

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Weather: 4.H.3 _________________________________________________________________ Weather and Classical Instruments Grade Level 4

Sessions 45 min. Seasonality N/A Instructional Mode(s) Whole class Team Size N/A WPS Benchmarks 04.SC.ES.01

04.SC.ES.07 04.SC.ES.08

MA Frameworks 3-5.ES.6 3-5.ES.8

Key Words Meteorologist, Atmosphere, Weather, Instrument, Component

Summary This session is aimed to help the students understand the components of weather and how we measure the components. The teacher will present a lecture of what the weather consists of and what instruments may be used to determine the different levels of this weather.

Learning Objectives 2002 Worcester Public Schools (WPS) Benchmarks for Grade 4 04.SC.ES.01 Describe how global patterns such as the jet stream and water currents influence local weather in measurable terms such as temperature, wind direction and speed, and precipitation. 04.SC.ES.07 Explain how air temperature, moisture, wind speed and direction, and precipitation make up the weather in a particular place and time. 04.SC.ES.08 Use a collection of classical (not digital) weather instruments that clearly shows the physical principle that makes them work.

Additional Learning Objectives 1. Explain how air temperature, moisture, wind speed and direction, and

precipitation make up the weather in a particular place and time. 2. Describe how global patterns such as the jet stream and water currents influence

local weather in measurable terms such as temperature, wind direction and speed, and precipitation.

Partnerships Implementing Engineering Education Worcester Polytechnic Institute – Worcester Public Schools

Supported by: National Science Foundation

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Required Background Knowledge None

Essential Questions 1. What is weather?

Introduction / Motivation None

Procedure The instructor will: 1. Ask students what weather is and have them write their ideas in their journal. 2. Give them to correct definition of weather and have them write it down. 3. Go over the components that make up weather. (See attachment) 4. Explain that a weather instrument measures each component. 5. Show transparencies of classical weather instruments and explain how each

works. (See attachments)

Materials List Materials per Class Amount Location

None None None

Vocabulary with Definitions (in alphabetical order) 1. Meteorologist – Meteorologist: a person who studies the earths atmosphere

and weather conditions. 2. Atmosphere – Atmosphere: A layer of gases surrounding a planet 3. Weather – Weather: It describes the condition of the air at a particular time

and place. Weather also tells how the air moves (wind) and describes anything it might be carrying such as rain, snow or clouds. Thunder, lightning, rainbows, haze and other special events are all part of weather.

4. Instrument – Instrument: a device that is used to make measurements of something

5. Component – Component: one piece of a larger system

Partnerships Implementing Engineering Education Worcester Polytechnic Institute – Worcester Public Schools

Supported by: National Science Foundation

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Assessment / Evaluation of Students The instructor may assess the students in any/all of the following manners:

1. None

Lesson Extensions None

Attachments 1. Components of Weather 2. Weather Instruments (pictures for transparencies)

Troubleshooting Tips None

Safety Issues None

Additional Resources None

Key Words Meteorologist, Atmosphere, Weather, Instrument, Component

Components of Weather Note: This is intended for the teacher to teach, not as vocabulary words.

Depending on where you look for information, weather is classified by the first 4

components or by all 6.

INTRODUCTION

Weather happens every day. But what exactly is weather? Weather is made up of many parts. One part is temperature. Temperature is how hot or cold the air is. Another part of weather is precipitation. Precipitation is water that falls from the sky to Earth. The water can be a liquid. It can be a solid. Or it can be a mixture of the two. Rain, snow, sleet, and hail are types of precipitation. A third part of weather is wind. Wind can be a gentle breeze. It can also be a strong tornado. All of these parts are affected by air pressure. Air pressure is the fourth major part of weather. As the phrase implies, air pressure is the pressure that air exerts on Earth's surface.

TEMPERATURE

The measurement of how hot or cold something is. Atmospheric temperature can be affected by sunlight, wind, latitude, altitude, and the land surface.

Temperature can also be affected by surface reflections. Heat is a form of energy caused by the internal motion of molecules. The slower the molecules are moving, the less heat is present. Temperature is a

measure of heat energy in a substance

WIND

- The movement of air relative to the surface of the earth. It’s considered to be severe if 58 m.p.h. or greater. Hurricane winds are 74 m.p.h or greater and the highest tornado winds are about 318 m.p.h.

Winds are created when there are differences in air pressure from one area to another. In an area where there is low-pressure (rising air), air at ground level comes in to replace the air that is rising. In areas of high-pressure (sinking air), air at ground level spreads out.

If a high and low pressure area are close to each other a strong wind will develop, because a natural circulation of air will occur (see diagram below.) The greater the difference in pressure is, the stronger the wind.

Winds can be produced in a localized area, to expanses of several hundred miles. An example of a local wind is a land-sea breeze. During the day, land will heat up faster than water, which makes air rise over the land – a low-pressure area is formed. Since the water is cooler, there is higher air pressure over the water. Air from over the water comes inland to replace the rising air, making a sea breeze. At night, things are reversed – the land cools down quickly, while the water stays warmer. High pressure is formed over the land and low-pressure forms over the water, so air flows offshore. This is called a land breeze.

PRECIPITATION

The General name for water in any form falling from clouds. This includes rain, drizzle, hail, snow and sleet.

Although, dew, frost and fog are not considered to be precipitation. ( we will study this in detail is session 2)

AIR PRESSURE

The weight of air pressing down on earth. Air pressure can change from place to place, and this causes air to

move, flowing from areas of high pressure toward areas of low pressure. It’s the same as barometric pressure.

HUMIDITY

The amount of water vapor in the air (water vapor is a gas in the atmosphere. There is very little of it in the air. Water vapor is only 1 to 4% of the atmosphere, but without it we would have no clouds, rain, or snow.

Water vapor is one of the greenhouse gases, which help to trap the earth's heat).

CLOUDS

A visible collection of tiny water droplets or, at colder temperatures, ice crystals floating in the air above the surface. Clouds come in many different sizes and shapes. Clouds can form at ground level, which is fog, at

great heights in the atmosphere, and everywhere in between. Clouds offer important clues to understanding and forecasting the weather. Clouds not only provide rain and snow, but help retain heat, so it does not all

escape into space.

Weather Instruments Barometer:

Definition:

The aneroid barometer is an instrument that measures the pressure of the air. How it works:

The atmospheric pressure changes as the weather changes. It goes up and down. We say the pressure is rising, is falling, or is steady. An aneroid barometer works with a small capsule that acts like a bellows. Air

has been removed from the capsule. When the air pressure increases, the sides of the capsule are pushed in and the connected needle rises (clockwise). If the air pressure decreases or falls, the sides of the small

capsule puff out and the needle moves in the counter clockwise direction. The numbers are based on the principle that atmospheric pressure supports 30 inches of mercury in a tube of mercury with one end sealed.

What it tells us: When the air is dry, cool, and pleasant, the mercury or barometer reading rises. When the air is warm and

wet, the barometer reading falls. When the air pressure falls, it usually indicates some type of storm or wet weather is coming. When it rises, it often means clear weather. If the barometer remains steady, there will

be no immediate change in the weather. The more rapid the change, the sooner the weather will change. A change of even one-tenth of an inch is a significant change.

Anemometer

Definition: The anemometer measures wing speed How it works:

There is a free moving turbine suspended in the middle of the anemometer. This turbine, when held correctly, moves at the speed of the wind. The speed of the turbine is sensed by an infrared light that relays the signal to an electrical circuit that digitally displays it. What it tells us: The electronic model can accurately show the speed of the wind in miles per hour or knots.

Force Speed mph Describe Effect 0 1 Calm Smoke straight up 1 3 Light breeze Smoke slightly bent 2 7 Light air Leaves rustle 3 11 Gentle breeze Leaves move 4 19 Moderate breeze Small branches move 5 24 Fresh breeze Small trees sway 6 31 Strong breeze Large branches move 7 38 Moderate gale Whole trees move 8 46 Fresh gale Twigs break off 9 54 Strong Gale Roofs damged 10 63 Gale Trees uprooted 11 73 Storm Widespread damage 12 74+ Hurricane Widespread destruction

Rain Gauge Definition: The rain gauge measures the amount of liquid precipitation that falls. How it works: The rain gauge has an outer cylinder, a measuring tube, and a funnel. The measuring tube measures to a hundredth inch. When it is full, it contains one inch of rain. When more than an inch falls, the extra flows into the outer cylinder. By carefully pouring the rain from the outer cylinder back into the measuring tube, a total rainfall amount can be accurately measured. What it tells us: It measures the total rainfall in a specific area.

Hygrometer Definition: The mechanism in a hygrometer measures the amount of moisture in the air (humidity). How it works: The hygrometer contains a humidity sensitive element that absorbs and disperses the humidity (moisture) in the air around it. In this case, the element is a small spiral floating in fluid. The spiral winds and unwinds as the moisture from the surrounding air is absorbed or released. This motion is transferred to the indicator hand, which moves on the reading surface. It takes approximately four hours in a fairly windless atmosphere for the indicator to relate the change in humidity level. What it tells us: It tells us the relative humidity (The ratio of water vapor in the air to the maximum amount of vapor the air can hold at a given temperature and pressure; the "wetter or damper" the air feels the higher the relative humidity. The drier the air feels the lower the relative humidity.)

Thermometer Definition: A thermometer is an instrument used for measuring temperature. How it works: Bulb thermometers rely on the simple principle that a liquid changes its volume relative to its temperature. Liquids take up less space when they are cold and more space when they are warm. When you look at a regular outside bulb thermometer, you'll see a thin red or silver line that grows longer when it is hotter. The line goes down in cold weather. This liquid is sometimes colored alcohol but can also be a metallic liquid called mercury. Both mercury and alcohol grow bigger when heated and smaller when cooled. Inside the glass tube of a thermometer, the liquid

has no place to go but up when the temperature is hot and down when the temperature is cold. What it tells us:

The temperature can be read by looking at the numbers on the tube that corresponds to the height of the line.

Barometer

Anemometer

Rain Gauge

Hygrometer

Thermometer