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Weather planning information

Weather - inspired by CoraLynn Malmberg

Some people are weatherwise, but most are otherwise.
Benjamin Franklin

From where we stand the rain seems random.
If we could stand somewhere else, we would see the order in it.

Tony Hillerman, Coyote Waits

Introduction

A variety of people have studied weather over the years who have added to our knowledge about the causes and effects of weather.

Prior knowledge:

Boat in weather

For learners to conceptualize concepts related to weather, the water cycle , and how weather changes, it's necessary for them to have some background knowledge in temperature, thermometers, heat energy and air pressure. For example. Knowing air has mass and the mass of the Earth’s atmosphere exerts pressure (air pressure barometric pressure) or pushes on us and all objects from every direction. That pressure changes with altitude (1kg / cm 2 or 15 pounds / square inch at sea level) and temperature.

Therefore, prior activities such as:

are necessary if learners are to understand what causes weather and how it changes.

That doesn't mean younger learners can't benefit with weather related experiences. A good place for them to start is to make weather instruments and record their own weather observations and match them to drawings and photos of weather related pictures in books or in other media.

Intermediate learners are able to create weather instruments (engineering activities related to technology and science) to collect meteorological data and use it to look for weather patterns. Learners may also research weather and use weather databases to investigate weather patterns. For example how does the barometric pressure change before and after storms?

Weather instruments & suggestion for making them

Barometer or Thermometer?

Concepts

  • Volume of air and water change with temperature.
  • Volume of air and water change with pressure.
  • Atmospheric pressure is created by the mass of the atmosphere.
  • Temperature equipment can be constructed and calibrated to record temperature.

Barometer

Materials

Coffee stirrer or very narrow straw, wide mouth jar, 14 inch balloon, heavy rubber bands, white glue, ruler.

Barometer plan

Procedure

Cut a piece of balloon large enough to stretch over the mouth of the jar and hold it in place securely with the rubber bands. Glue the stir to the center of the balloon. Set it beside a card stock poster

Explore

  • Is this instrument more sensitive to pressure or temperature?
  • How might you calibrate it?

 

Thermometer

Materials

Straw, ruler, silicon or glue, food coloring, small glass or plastic bottle, screw cap with a hole the size of the straw, or modeling clay.

Procedure

  • Fill the bottle half way with water and add a few drops of food coloring
  • If you have a cap with a hole, put a straw through the hole in the cap and adjust it so it will be near the bottom of the bottle, but not on the bottom. Then seal it, with the (silicon, glue, or clay) so the straw extends above the cap. Do not pinch the straw or seal it or it will not work.
  • Or you could just seal the straw in the bottle in the same way with the modeling clay.

Explore

  • Is your instrument more sensitive to pressure or temperature?
  • How might you calibrate it?
    • Make marks for different temperatures on the bottle or add a strip of tape to write on.
    • Place your thermometer in different places along with a calibrated thermometer and add the temperatures beside the mark the water is closest to. Try ice water, hot water, and at room teperature to calibrate yur scale.
  • Is water or alcohol more sensitive to temperature? Make another one so have two: one with water and the other with rubbing alcohol.

 

Find the Dew point

Concepts

  • Dew point is the temperature (F) that water in the air will condense.

Materials

Metal can, water, ice, thermometer.

Procedure

Fill a metal can about a third full of water at room temperature. Add one ice cube at a time and stir with a thermometer until the ice cube melts or there is condensation on the side of the can. When there is condensation on the side of the can the temperature of the water is the dew point.

To measure the dew point when the temperature is below freezing, use salt and record the temperature when there is frost on the can. If salt is used, handle the can with winter gloves as it may cause frost bite. Water vapor will condense directly into frost.

 

Measure Relative Humidity with a psychrometer

Concepts

  • Air has the capacity to support water (moisture) and the amount of moisture varies by temperature.
  • Humidity is the water vapor in the air.
  • Absolute humidity is the actual amount of water in the air.
  • Relative humidity is the ratio between the actual amount of water vapor (absolute humidity) at a certain temperature and the maximum amount of water vapor the air can hold at that temperature.
  • Percent of relative humidity equals 100 times the amount of water vapor actually in the air divided by the maximum amount of water vapor the air at that temperature can hold.

Materials

Thermometers, shoe string or cheese cloth, small container for water reservoir.

Psychrometer

Procedure

You can make a psychrometer by attaching two thermometers to a hard piece of craft board or thin plywood. Then drilling a hole for string so it can be gently swung around in a circle. The dry bulb can be covered with a bottle cap that has a slit to allow the stem of the thermometer to enter.

The wet bulb can be wrapped with cheese cloth or a piece of a shoe string so water can be added before operating it and kept wet while it is in use. If you have distilled water, you can use it to avoid calcium build up over time.

Take the psychrometer out doors and getly move it around in a circle checking the thermometers after every six - eight circles. When the temperatures do not change after a couple of checks record the wet and dry temperatures and use the chart to find the relative humidity.

Relative humidity chart

Heat index

 

Why is the wet bulb temperature different? When water evaporates into the air it creates a cooling effect, but the amount of this cooling varies, depending on the overall air temperature and the relative humidity. The wet-bulb temperature measures how cool the air can become through water evaporation.

A Hygrometer uses two different materials that interact with humidity differently and compare how they change to determine the relative humidity.

Hygrometer

Wind Vane and Anemometer

Concepts

  • Wind has speed and direction
  • Wind direction is measured by a wind vane
  • Wind speed is measured by an anemometer
  • Beaufort Scale is a measurement system of wind speeds, in numbers from 0-17.

Materials

Straws, pins, stapler, poster board, small paper drinking cups

Procedure

Cross two straws in the middle, attach the cups at each end all facing the same direction,

Flag observation method

Another way to determine the wind speed of a flag is how much it is moving in the wind. When watching a flag flying on an in-ground flagpole, there are few ways it could be waving. Who knew there were multiple ways a flag could fly.

  • If the flag is not moving, then the wind speed is below 11 mph.
  • If the flag is moving subtly and sporadically, then the wind speed is between 12-18 mph.
  • If the flag is waving it’s entire length but in a gentle motion then the wind speed is between 19-24 mph.
  • If the flag is waving more violently over its entire length then the wind speed is 25-31 mph.
  • If your flag is fully extended and constantly flapping then the wind speed is 32 mph or more.

When there is a high wind day, you should take your flag down, if possible, to extend the life of your flag. A flag will start to fray and will last longer if you take it down for a day or two.

Measuring degrees of flag from its pole to determine

When a flag is on a pole perpendicular to the ground, you can use the angle between the pole and the bottom side of the flag to estimate the wind speed by dividing the anglee by 4. For example, if the angle of your flag from the pole is approximately 40 degrees, the wind speed is roughly 10 mph (40/4).

Using a wind sock

Wind sock

Weather station

A simple weather station that has a rain gage, thermometer, wind vane, and device to measure wind.

Weather station

Rain gauge

Materials

Two liter plastic bottles with the top cut off touse as a funnel & ruler;

A tall olive jar or other jar may be used if it has the same size opening as its bottom. Another idea is to place a funnel on top of another container. Again make sure the size of the funnel mouth is the same size as the bottom of the container in which it is placed.

Procedure

Cut the top off the bottle, put about an inch of sand or water into the bottom of the bottle to level the bottom of the container and add ballast so the bottle won't blow away. Invert the top and place in on the bottom, attach a ruler, calibrate, and set it out side away from obstructions.

 

 

Activities

Snow

Concepts

Materials

Snow

Procedure

  1. Collect snow.
  2. Observe it. Temperature, size - mass, volume, weight, ...
  3. Melt it.
  4. What changes do you observe?
  5. How did the amounts change or not change?
  6. Was there something more than water in the melt? If so, what was included?
  7. Where did it come from?

Water cycle

Materials

Plastic soda bottle, sand or gravel (optional will retain heat longer), hot water, food coloring, aluminum foil or aluminum container, ice.

Concept map

Water cycle map

For learners who understand volume and pressure try the activity Cloud in a bottle

Procedure

  1. Take the plastic soda bottle and cut off the top.
  2. Mold foil or aluminum container to fit around the top of the bottle and has a bowl shape on top of the bottle to hold four or more ice cubes.
  3. Place the sand or gravel into the bottle and pour enough very hot water into the bottle to cover the sand and gravel and have about 2 cm of water above the sand and gravel.
  4. Drop two drops of food coloring into the water. For effect!
  5. Put the aluminum bowl cap onto the soda bottle.
  6. Check the aluminum foil for leaks.
  7. Place the ice into the aluminum container.
  8. Watch the entire system and see what happens.

Solar Energy and Weather

Concepts

  • The Sun transfers heat to the Earth.
  • Seasons are caused by the tilt of the Earth’s axis (23.5 degrees)
  • A variety of variables (water, land forms, vegetation, color, soil,) effect the suns transfer of energy (radiation creates different amounts of heat depending on the matter that absorbs it).
  • Differences in the amount of heat energy and differences in the rate of transfer from different materials create convection currents.
  • Convection currents create weather changes.

Procedure

Graph or sketch the relative position of the sunrise or sunset for a period of time. How does the sun's position in the sky affect heat energy on Earth?

Procedure

  1. Graph the solar energy for a period of time (local forecast or Online).
  2. Graph the temperature over the same a period of time.
  3. Compare the solar energy graph to the temperature graph.
  4. What patterns do you notice?

Materials : Thermometer, plastic storage bags, three different colored sheets of paper

Procedure

Fill each plastic bags with the same amount of water, place outside in the sun with different colored sheets of paper under each, record the temperature after ... hours

Materials

Thermometer, different outside areas

Procedure

Place thermometers outside on different soils or kinds of vegetation and record the temperatures.

Materials

Thermometer, outside areas

Procedure

  1. Place thermometers outside at different heights (6 inches below ground, surface, above surface).
  2. Record the temperatures.
  3. What variables affected the temperature?

Materials

Thermometer, outside areas

Procedure

Record the temperature at the bottom of a hill, at intervals up the hill, at the top, down the other side, and at the bottom of the other side.

Materials

Thermometer, plastic bags, and student made solar house.

Procedure

  1. Put 1 liter of water, and a thermometer into a plastic bag.
  2. Seal the plastic bag and place it into the solar house.
  3. Place the solar house outside in the sun for 4-5 hours.
  4. Read the thermometers, compare, and discus.

Relation of energy costs to temperature

Concepts

There is a relationship to temperature and heating and cooling costs.

Materials

Source of monthly temperature averages, energy bills.

Procedure

Graph the temperature averages for a series of months and the cost of energy to heat and cool a building.

Climate is?

Concepts

  • Temperature and precipitation are variables that effect climate.
  • Earth's climate is controlled by its oceans and their circulations.
    • Ocean water at the polar regions freeze, which removes salt and causes the water around it to increase its density and makes it heavier. This heavy cold water sinks to 13,000 feet or more and begins to flow north into the Earth's ocean basins. Over decades of time it flows slowly toward the subtropics where it moves to the surface and pushes the warm water there toward colder latitudes (north toward the north pole and south toward the south pole). Where it cools, begins to freeze and starts the loop over.
    • These ocean currents are important to move nutrients, heat, carbon , oxygen, and organisms around the globe to feed phytoplankton, which fuels the ecosystem as well as control the climate.
    • If the temperature differences are decreased (by global warming) the polar water will be less salty, less dense, and thus slow the current as less dense water will not sink as fast and slow the flow of the current. If there is no ice, then the current will stop all together.
  • With global warming reducing the temperature differences in seasonal change, the Earth will not be cold enough to create enough ice to maintain ocean currents, the Earth will warm and melt large amounts of ice, which will create larger amounts of fresh water, which will decrease the saltiness of the oceans. Without currents to stir the oceans there will be a collapse in the present ecosystems that relies on the nutrients and other resources the ocean provides. Without ocean life all life on the planet will change.

Materials

Source of temperature averages and precipitation.

Procedure

Make a climograph (a graph with monthly temperature and precipitation).

Iceberg
Ice shelf break off makes an iceberg and floats off to make sea ice

 

How do temperatures change?

Concepts

Temperature ranges vary consistently with the normal temperature.

Materials

Source for daily normal, high, and low temperatures.

Procedure

Make a temperature scroll. Graph the normal temperature, observed highs, observed lows, and shade the area above and below different colors.

Temperature and place

Concepts

  • Position of a thermometer effects the temperature it records.
  • Fact - Meteorologists from around the world have agreed to record temperatures from inside a white louvered building at a height of 4-5 feet (1.2-1.5 m) above the ground in a grassy area.

Materials

Thermometers, outside areas

Procedure

Collect information for the following question:

  1. Where is the thermometer on the bank or other places?
  2. How much of a difference does it make if thermometers are located at different places?
  3. Does it really make a difference?

Land formations and weather

Concepts

  • A variety of variables (land formations, water masses, man made objects, plants, Earth’s rotation, pressure) affect wind.
  • Friction from (land formations, water masses, person made objects, plants)

Materials

Safety concerns - Matches, candle, objects.

Procedure

  1. Make sure learners are aware of safety procedures necessary with candles.
  2. Try to blow out the candle with different objects between them.
  3. Diagram how the wind moves around the objects.

Wind and land formations

Concepts

Wind affects land formations on Earth.

Procedure

Take a field trip and pictures of dunes or snow drifts. Explain how they were created.

Find other activities on erosion 1 and/or erosion 2.

Wind and weather

Concepts

  • Earth's rotation (Corollas Force)
  • High pressure air spirals out (Pressure, Corollas, and friction)
  • Low pressure air spirals toward the center.
  • Buys Ballot's law (Christoph Buys Ballot) With your back to the wind, turn 30 degrees to your right and the high pressure is to your right and the low pressure is to your left. (120 degrees from where originally facing).

Weather fronts / cold and warm air

Concepts

  • Differences in temperature create winds.
  • Isotherms are lines created by connecting places with equal temperatures.
    • If you stand on an isotherm with the cold temperature to your left and warm temperatures to your right, the upper level winds would be blowing from your back to your front.
    • Generally the closer the isotherm lines the greater the winds. Where the isotherms are the closest is generally where the jet stream is found.
  • The jet streams usually carry the ground-level weather systems along with them.

Materials

Clear container (about 5 liters), hot water, cold water or ice, pepper, plastic bag.

Procedure

Put the ice or cold water into the plastic bag and seal it. Fill the container with hot water, stir in some pepper until you have a fair distribution of pepper. Place the bag into it and observe the convection current.

Materials : Clear container (about 5 liters), hot water, and 100 ml of cold milk.

Procedure

Put the hot water into the clear container. Slowly pour the milk down a narrow side of container. You should see a convection current know as a downburst.

Clouds

Concepts

Clouds shape and height of clouds determine the type of precipitation.

Materials

Camera, drawing materials to record clouds (white chalk & blue paper), media with pictures of cloud types identified

Procedure

Take pictures or draw pictures of clouds and research the type. How high they are, what kind of moisture they contain, what kind of weather usually accompanies them.

Clouds, how fast are they?

Materials

Watch, sky

Procedure

  1. Locate some cirrus clouds
  2. Select a starting point and stopping point so the cloud you are timing will travel half way across the sky.
  3. The distance from a person to the horizon varies depending on how far off the ground their eyes are and if there are mountains on the horizon. However, on the ocean a 6 foot tall person can see 3 miles. The equation to calculate this is: Square Root(height above surface / 0.5736) = distance to horizon
  4. Assume your eyes are 5.5 feet above the ground, then
  5. Square Root(5.5 / 0.5736) = 3 miles.
  6. The speed = 3 miles / time in hours
  7. Can you figure how fast clouds travel?

Water cycle, precipitation, and weather

Concepts

  • Change in pressure causes changes in weather.
  • High pressure: winds clockwise, good weather,
  • Low pressure: winds counterclockwise, means bad weather
  • Water particles attract (adhesion) to other water particles.
  • Air can support water vapor.
  • The most water vapor air can support is about 4%.
  • Water drops will grow (coalesce) when other drops collide.
  • Dew point is the temperature at which condensation will occur.
  • Warmer air can hold more water vapor than cold air.
  • Precipitation can be of different sizes
  • Precipitation (rain, drizzle, sleet, snow, hail, virga) is a result of the water cycle .
  • Condensation, evaporation, transpiration, sublimation, deposition,
  • A variety of variables affect the rate of evaporation (amount of heat, surface area, humidity, wind speed, air pressure) and condensation.
  • Evaporation and condensation result in an energy transfer.
  • The total amount of water on Earth is constant.
  • Dew point, relative humidity, and temperature are related.
  • Clouds form from water vapor.
  • When air cools below its dew point water vapor condenses (into water (dew fog, clouds) or ice (frost)) on particles (dust, pollution, volcanic ash, smoke, salt spray) and forms clouds.
  • Water vapor in clouds is so small that air can easily support it (like fog).
  • When water vapor particles collide they coalesce and may eventually become heavy enough not to be supported.
  • Rising air expands due to less pressure and transfers heat energy into motion and cools to its dew point temperature.
  • Conduction, convection, and radiation transfer energy to form clouds.
  • Looking for cloud shapes is called nephelococcygia, or "cloud cuckooland".
  • Contrails are condensation trails from high aircraft. Created when moist warm air from the aircraft exhaust is quickly chilled.

Foggy mirror

Materials

Mirror

Procedure

  1. Put a mirror by your mouth and breathe.
  2. What happens? Explain why.

Sweaty glass

Materials

Ice, small glass or plastic container, lid, water.

Procedure

  1. Put the ice and water into the glass or plastic container.
  2. Observe.
  3. From where did the moisture come?
  4. Inside the container?
  5. Put a lid on the container and repeat the experiment.

Spray and drip

Materials

Water mister or spray bottle, water, plastic or glass surface.

Procedure

Spray water on the surface, observe, repeat the process and see what happens.

Rain drop fossils

Materials

Corn starch, cookie sheet, strainer, rain storm.

Procedure

  1. Lightly sprinkle the cookie sheet with corn starch and place it in the rain for 5 seconds.
  2. Pour the cornstarch through a fine mesh strainer.
  3. Most of the starch will pass through the strainer and you will be left with raindrop fossils.
  4. These will be larger than the original raindrops. Why?
  5. Sort and count the rain drops.
  6. Record the rain event and save the raindrops in a carefully marked and sealed plastic bag.
  7. Repeat the process on other rainy days.
    • Is there a relationship between the size and number of drops?
    • The kind of rain and the number of drops?
    • How much rain there was and the size of drops?
    • Compute the area of the rain drop collector.
    • How many raindrops fell per square inch in a minute? Per hour?
    • How many would fall on a football field? City block? Square mile?

Snow prints

Materials

Scotch tape, snow, construction paper.

Procedure

  1. Collect snow flakes on the scotch tape.
  2. Answer the same kinds of questions for the rain fossils activity.

Evaporation

Materials

Alcohol, water, other liquids, cotton balls.

Procedure

  1. Swab some liquid onto your skin.
  2. What happens?
  3. Which of the liquids cause your skin to feel the coolest?
  4. Why?
  5. How does this fit with perspiration?

Model atmosphere

Materials

Plastic containers, water, masking tape, lamp, sack of sand.

Procedure

  1. Put water in one of the containers with the sand bag on one end.
  2. Invert another container onto the first.
  3. Seal the two with masking tape.
  4. Set the device under the lamp and let sit for a few hours.
  5. What do you observe?
  6. What would happen if ice were set onto the top of the top container?
  7. What would happen if the lamp were on the opposite end?

Holding water

Materials

Cotton balls, string, eye dropper, water.

Procedure

  1. Hang a cotton ball on a piece of string.
  2. Drop water on the cotton ball.
  3. What happens?
  4. What would happen if you added twice as much water to a second cotton ball?
  5. What would happen if you had a cotton ball that could hold twice as much water?

Materials

Sponges of different sizes, string, eye dropper, water.

Procedure

  1. Hang a sponge piece on a string.
  2. Drop water onto the sponge.
  3. How much will it hold?
  4. Repeat with different sizes of sponges.
  5. What do you discover?

 

Dew Point Temperature degrees F Water Vapor grams/cubic meter of air Temperature degrees F
0 1.31 0
10 2.03 10
20 3.06 20
30 4.53 30
40 6.57 40
50 9.4 50
60 13.33 60
70 18.58 70
80 25.49 80
90 34.49 90
100 46.05 100
110 60.73 110

 

Dew point

Find a pattern between the recorded dew point, relative humidity, and temperature.

 

What will air hold?

Materials

Vacuum cleaner, ping pong ball.

Procedure

  1. Put the hose of the vacuum cleaner so it is blowing air.
  2. Float the ping pong ball in the stream of air.
  3. Can you float larger balls?

Cloud in a bottle

Materials

2 liter plastic pop bottle, warm water.

Procedure

  1. Fill the bottle three-fourths full of very warm water, quickly cap the bottle, gently squeeze and release the bottle.
  2. You should see a cloud.
  3. Squeeze again and see what happens.
  4. If you have a bottle keeper or pump you might want to see how pressure affects clouds.
  5. If the bottle gets foggy shake the bottle to clear the fog.
  6. If you can’t see a cloud you may want to use a flash light.
  7. Try all these again with the bottle one-fourth filled with water.

Clouds and Other sky events - Facts and Concepts

  1. Shapes of clouds are determined by how they are formed (cooling air moving vertically form large billowy clouds (cumulus) and horizontal moving cooling air form layers of clouds (stratus). Clouds can be classified into groups with common properties:
  2. Cirrus means curl and are thin wisps, streams, or waves 4.5 or more km high of ice crystals.
  3. Cumulus means heap and pile up like balls of cotton as they show where air is rising. They usually appear in the day, 1.5 km or lower, and disappear at night and are associated with good weather.
  4. Stratus means layer and are low layers of clouds at .6 km. They usually cover the whole sky and are associated with storms. Only drizzle or small grains of snow precipitate from true stratus. Sometimes two of these names are combined to describe clouds.
  5. Cirrostratus high thin curly layers of clouds that are transparent to sunlight. Many times they make a halo around the sun or moon indicating the coming of rain or snow.
  6. Stratocumulus layers of cumulus clouds that cover the sky at 1.5 km, contain more water than altocumulus and generally do not precipitate, especially during the winter.
  7. Cirrocumulus very small cumulus puffs of fluffy clouds at the cirrus level that are usually ice crystals. Sometimes prefixes are also added like alto meaning high, nimbus or nimbo meaning rain, and fracto meaning broken.
  8. Altostratus high stratus clouds (2.4 - 3.7 km) that are true rain and snow clouds Sun may shine dimly through these or be hidden.
  9. Nimbostratus are rain clouds.
  10. Cumulonimbus are thunder heads, can bring hail, high winds, and tornadoes. Height from .9 - 3.0 km with tops as high as 18 km or more. From a distance tops may look like an anvil.
  11. Fractocumulus broken cumulus clouds.
  12. Altocumulus are rounded cumulus at 2.4 - 3.7 km. Generally a fair weather cloud with puffs larger than cirrocumulus. Other sky events
  13. Sun dogs are bright colored spots in cirrus clouds at opposite angles to the sun.
  14. A halo is a ring around the sun or moon
  15. Crepuscular rays are rays of the sun that shine between clouds.
  16. Sunspots are dark spots or patches appearing from time to time on the sun's surface. Dark relative to its surrounding surface. The amount of sunspots tend to happen in cycles. See the chart of sunspots from 1750-1980.

Classify cloud pictures into categories.

Materials

Paper and pencil or white chalk and blue paper, optional camera, collection of cloud pictures.

Procedure

Keep a log of the clouds in the sky

Cloud height

Materials : temperature, dew point.

Procedure to estimate the height of cumulus clouds

  1. If the temperature is 60 degrees F and dew point is 60 degrees F, then there is fog and the cloud is at ground level.
  2. If the temperature is 70 degrees F and the dew point 60 degrees F, then the height is 2,000 feet.
  3. If the temperature is 80 degrees F and the dew point is 60 degrees F, then the height is 4000 feet.
    1. Subtract the dew point from the current air temperature.
    2. For every degree F add 200 feet or 60 m for the height of the cloud base.
  4. Check a airport weather report for the ceiling to see how accurate you are.

What color are clouds and the sky?

Materials

Paint chips or paint

Procedure

  1. Use paint chips of blue and gray colors or make your own by putting white paint on a pallet and adding one drop of blue, mix thoroughly and paint a 1 inch square around the edge of the paper. Add one more drop of blue, mix, and paint. Repeat the process until you have the darkest blue you think the sky will ever be. Then repeat the process with gray.
  2. Use color chips or your color chart to record the colors of the sky from day to day or hourly.

Destructive Weather

Concepts

  • Storms, thunder, wind, hail, tornado, hurricane, tropical storms, tropical cyclones, typhoons, cyclones, water spout, lightning, floods
  • Warm fronts move up through colder retreating air. The slope of the warm front is gradual and may travel 1600 km (1000 miles) to rise 8 km (5 miles).
  • As air rises it becomes cooler and water vapor condenses into large masses of clouds.
  • Cold fronts move through warm air and push the warm air up.
  • The cold front moves quicker because the cold front is heavier and pushes the lighter front out of the way.
  • As the warn air rises very quickly it condenses.
  • The quicker it rises the more violent the storm.
  • Stationary fronts have the air between the two masses mix over a long period of time and the slope is very gentle like that of a warm front.
  • Cold air masses have higher pressures than warm air masses because the cold air is heavier.
  • Low pressures have the lowest pressure in their centers and air blows toward the center in a counterclockwise direction (due to the rotation of the Earth).
  • High pressure have the highest pressure in their centers and air blows away from the center in a clockwise direction (due to the rotation of the Earth).
  • Lows usually bring bad weather because the warmer lighter in the center of the low pressure is pushed away by the heavier colder around it.
  • The warmer air rises, cools, and forms precipitation.
  • Lows usually travel about 1100 km (700 miles) per day in the winter and 800 km (500 miles) per day in the summer.
  • Highs usually bring good weather as the colder heavier air is falling toward the Earth.
  • As the cold air falls it becomes warmer and can hold more water vapor and hence no precipitation.
  • Tornadoes have wind speeds of 70-300 mph. (120-480 kph).
  • The forces from the wind, the sudden change of direction, and flying debris cause great damage.
  • Hail is created by accretion and updrafts.
  • Thunder and lightning are electric discharges. Lightning is hotter than the sun.
  • Why is lightning dangerous?
  • Thunder is caused when the air around the lightning is superheated. in less than a second, to 8,000-33,000 degrees Celsius. When air is heated this quickly it explodes.
  • In a six hour period in the Midwest there were 15,422 lightning strikes recorded.
  • In Florida from 1983-1990 the most common fatalities or injuries from lightning were, in order,
    • 1. near or in the water;
    • 2. near or under a tree;
    • 3. near a vehicle, home, or building;
    • 4. On a golf course, ball field, or similar situation.

Downburst

Materials

Clear container (about 5 liters), hot water, and 100 ml of cold milk.

Procedure

  1. Put the hot water into the clear container.
  2. Slowly pour the milk down a narrow side of container.
  3. You should see a convection current know as a downburst.

Materials

Clear container (about 5 liters), hot water, cold water or ice, pepper, plastic bag.

Procedure

  1. Put the ice or cold water into the plastic bag and seal it.
  2. Fill the container with hot water, stir in some pepper until you have a fair distribution of pepper.
  3. Place the bag into it and observe the convection current.
  4. Try different temperature differences and see if faster or slower currents are created.

Materials

Box or folded oak tag, strip of paper, pencils.

Procedure

  1. Cut the box or oak tag so the strip of paper can slip through a hole and create the effect of a moving picture.
  2. Draw a scene on the oak tag or box.
  3. Create the weather for three or four days that could travel over and through the scene.
  4. Label the warm air, cold air, draw clouds, high pressure, low pressure, and other weather events and be ready to explain how the events could actually interact to create a real life series of events.
  5. Or use weather data and illustrate the events related to the weather data.
  6. Remember weather is three dimensional.

Procedure

Describe how each of the following might be explained or try to prove or disprove one or more:

  • Red at night, sailor’s delight. Red in the morning, sailor take warning.
  • When clouds appear like rocks and towers the Earth’s refreshed by frequent showers.
  • When the wind is in the east, it is neither good for man or beast.
  • With dew before midnight, the next day will surely be bright.
  • The more cloud types present, the greater the chance of rain or snow.
  • When high and \/or middle-level clouds move from north to south and southwest, precipitation is more likely.
  • Precipitation is more likely to occur when clouds at different levels move from different directions.
  • A ring around the sun or moon, means rain or snow coming soon.

Hail

Materials

Safety Use winter gloves to handle the salt and ice container as the container may get cold enough to cause frost bite.

Crushed ice, several large test tubes, 500 ml beaker, salt, water, thermometer, stirring rod.

Procedure

  1. Fill a beaker three-fourths full with equal amounts of ice and cold water.
  2. Use winter gloves to protect hands from frost bite.
  3. Pour salt into the beaker and stir until salt doesn't dissolve and some remains on the bottom.
  4. Make sure the test tubes are totally clean and fill with cold water so the level of water is the same as the beaker when they are placed into the salt water in the beaker.
  5. Put the thermometer into the beaker.
  6. Put the test tubes into the beaker.
  7. Allow them to sit for ten minutes and stir inside the beaker occasionally with a stirring rod.
  8. At the end of ten minutes record the temperature.
  9. Remove the test tubes and immediately drop a small piece of ice into each.
  10. Remove the ice and repeat dropping it in.
  11. Record.
  12. Compare results from the other pieces of ice.
  13. Discuss your results.

Tornado in a bottle

Materials

2 liter pop bottle, water, drop of soap.

Procedure

  1. Put water into the pop bottle
  2. Cap the bottle.
  3. Turn it upside down, swirl it and observe (funnel).
  4. Might want to add less than a drop of soap and try again.
  5. Add different objects to the bottle and notice the direction of the current around the funnel and how it changes.

Lightning in bed

Materials

Objects with static cling, socks and carpet.

Procedure

  1. Create a static spark and snap.
  2. At night when you go to bed turn all the lights out.
  3. Get under the covers.
  4. Separate two blanks or a sheet and blanket and watch your own personal lightning show.

How far to a lightning strike

Materials

Thunderstorm.

Procedure

  1. Watch for lightning.
  2. When you see some start to count.
  3. When you hear the thunder stop.
  4. Take the number you counted to and divide by 5 (light travel about 5 times faster than sound 186,000 mph or 299,000 kph to 1000 feet/sec or 300 m/sec) that will give you the distance the lightning was from where you are.

Make a spark

Materials

Styrofoam plates, aluminum pie pan, tape, scissors, wool or felt pieces of cloth, small fluorescent tube.

Procedure - works best on a low humidity day. Won't work on rainy days.

  1. Cut two pie shaped pieces from one Styrofoam plate to make a handle for the aluminum pan.
  2. Fold them and tape them to the middle area of the aluminum pan.
  3. Set them on top of the other Styrofoam plate.
  4. See picture.
  5. Lift the aluminum pan with the Styrofoam handles.
  6. Rub the bottom of the pan with the wool. This will transfers electrons from the wool to the aluminum (charging it).
  7. As you put the pan back on the Styrofoam plate, so as much of each surface is touching, twist it a little to spread the charge.
  8. Then slowly move a finger toward the edge of the pan ... zap!
  9. Repeat and slowly move a small fluorescent tube toward the edge of the pan. Flash!

Research Benjamin Franklin and his experiments with electricity.

Franklin and kite

Hurricane related activities


Hurricane Classification
Saffir-Simpson Hurricane Intensity Scale
Hurricane Classification Saffir-Simpson Hurricane Intensity Scale
Category Pressure Winds Storm Surge Damage
1 28.94 or more 74-95 mph 4-5 feet minimal
2 28.5-28.91 96-110 mpg 6-8 feet moderate
3 27.91-28.47 111-130 mph 9-12 feet extensive
4 27.17-27.88 131-155 mph 13-18 feet extreme
5 27.17 or less Over 155 mph Over 18 feet catastrophic

 

Materials

Cookie sheet, water, hair dryer.

Procedure

  1. Fill the cookie sheet with water.
  2. Hold a hair dryer about 2 feet from the sheet.
  3. Blow air on low.
  4. What happens?

Materials

Cookie sheet, water, bowl, plastic tube.

Procedure

  1. Fill the cookie sheet with water.
  2. Place the bowl upside down into the water.
  3. Insert a plastic tube through the water into the bowl and suck air from the bowl.
  4. What happens to the water level in the bowl?

Materials

Sand and lake or ocean.

Procedure

  1. Make a sand castle near the shore.
  2. What happens when the waves wash at the castle?

Materials

Cookie sheet, clay, water.

Procedure

  1. Create a shore line that looks like Tampa bay or Mobile Bay.
  2. Add water and tilt the container to simulate a storm surge.
  3. What happens?

Materials

Procedure

Research newspaper microfilm or other sources from historic hurricanes such as

  • Camellia August 14-22, 1969;
  • Gilbert September 8-19, 1988;
  • Hugo September 16-24 1989;
  • Andrew August 22-26, 1993 Miami Herald;
  • Hurricane Sandy, 2012;
  • Hurricane Katrina, 2005

Hurricanes 1980 -2021

Hurricanes 1980 to 2021

Wind chill or feels like temperature

Materials

Wind-chill = air temperature - 1.5 * wind speed wind chill chart

Humidity

Humiture Chart

Air is composed of 99% nitrogen and oxygen, the rest is carbon dioxide, water vapor, and argon.

What is Wet Bulb Temperature?

When water evaporates into the air it creates a cooling effect, but the amount of this cooling varies depending on the overall air temperature and the relative humidity. Wet-bulb temperature measures how cool the air can become through water evaporation. Which is influenced by both temperature, sunlight, and humidity. Essentially, it reflects the body’s ability to cool itself through sweating.

Materials

2 test tubes, 500 ml beaker, iron filings or steel wool, stand with supporting clamps, glass marking pencil or pen.

Procedure

  1. To find the percent of oxygen in air.
  2. Put some steel wool or sprinkle some iron filings into a damp test tubes.
  3. Fill the beaker with water until it is two thirds full
  4. Invert the two test tubes and attach them so that their mouths are below the surface of the water.
  5. Let the apparatus sit for 24 hours.
  6. Mark the water level in both test tubes.
  7. Let the apparatus sit for 24 more hours.
  8. Repeat until the water level remains the same for two consecutive days.
  9. Mark the test tube and calculate the volume of water that has displaced the air.
  10. This was the percentage of oxygen in the air.
  11. Why?

Wet Bulb Globe Temperature (WBGT)

Wet Bulb Globe Temperature (WBGT), is designed to give a more accurate measure of heat stress the weather can have on your body.

It uses measurements of environmental factors that affect heat transfer between the human body and our immediate environment: air temperature, relative humidity, the sun’s angle of intensity, wind speed, and cloud cover (solar radiation) to calculate a holistic determination of a weather heat stress index.

Knowing the WBGT isn’t just for meteorologist, it’s important for anyone who spends time outdoors to know so they can maintain a healthy body temperature and avoid heat related illnesses.

Think of it as a simplified weather report to keep you safe. Whether you’re an athletic trainer or participating in outdoor activities, knowing WBGT can be a life saver for heat safety.

WBGT numbers indicate your body’s true heat stress. It is different than the heat index, or feels like temperature, which only uses temperature and humidity to calculate it.

Calculating the WBGT

While it is easier to use a WBGT calculator than crunch the numbers yourself, it is interesting to understand how this metric is determined.

An easy way to calculate WGBT is using the OSHA.gov calculator by entering the required information. Doing so will familiarize you with the measurement of what environmental factors are used in its determination.

Another way to calculate it is to take measurements and plugging them into a WBGT formula such as one of the two below:

Wet bulb globe temperature (in Fahrenheit) is calculated with a formula:

WBGT = (0.7 * Tw) + (0.2 * Tg) + (0.1 * T)

In this WBGT formula, there are three important variables to note:

  1. T = Temperature in Celsius
  2. Tg = Globe Thermometer Temperature (in Celsius) – this is measured by a thermometer placed in a special black globe to estimate solar radiation without the effects of the light itself
  3. Tw = Wet-bulb Temperature (in Celsius)

Here is a rather complex equation for wet bulb temperature (WBGT):

  • Tw = T * arctan[0.151977 * (rh% + 8.313659)^(1/2)] + arctan(T + rh%) – arctan(rh% – 1.676331) + 0.00391838 *(rh%)^(3/2) * arctan(0.023101 * rh%) – 4.686035
  • T is the temperature in Celsius,
  • rh represents the relative humidity.

How to use the WBGT

Values of the heat stress index for the WBGT (wet-bulb globe temperature)

  • Below 80, require no extra precautions for normal activities, just monitor fluids.
  • 76-82 Plan intense or prolonged exercise with discretion and monitor fluids.
  • Between 80-90, the body will stress within 20-45 minutes of work or exercise in direct sunlight, with the time it takes to become stressed shortening as the WGBT goes up. Limit intense or prolonged exercise with discretion and replenish fluids accordingly.
  • Above 90, the body will stress in just 15 minutes and it is crucial to drink plenty of fluids and take very frequent breaks in the shade. as the index reaches and rise above 95 consider canceling exercise or provide appropriate fluids and cooling.

Considerations

  • WBGT should be checked every 20 to 30 minutes during the event with activities being adjusted accordingly.
  • Weather apps can be used to check the WBGT, however they are not timely with a lag time of several minutes
  • A handheld device for the specific purpose is more accurate as it can give real time readings.

What is Wet Bulb Temperature?

When water evaporates into the air it creates a cooling effect, but the amount of this cooling varies depending on the overall air temperature and the relative humidity. Wet-bulb temperature measures how cool the air can become through water evaporation. Which is influenced by both temperature, sunlight, and humidity. Essentially, it reflects the body’s ability to cool itself through sweating.

What is heat stress?

Heat stress experienced by a person depends on: The production of heat inside the body, that results from physical activity and its rate of transfer between the body and the weather conditions of the environment it is in.

To understand heat stress created by the interactions of the body and the environment, you need to consider temperature, humidity, wind speed, sun angle, and cloud cover (solar radiation).

The clothing that is worn by individuals, will modify the exchange of heat.

WBGT heat stress measurement should take all the contributing factors listed above into consideration. The resulting WBGT calculation can aid in mitigating the risk of heat-related illness.

Heat-related illness can vary from mild to severe. For example;

  • Mild heat-illness can be a person experiencing dizziness or weakness.
  • Heat exhaustion is mid-spectrum where a person may collapse, experience headaches, low blood pressure, and lethargy.
  • Heat-stroke is a dangerous form of heat illness; this is a severe condition and can result in permanent injury or death.

Reading weather maps

Weather maps

Materials: weather map.

Activity procedure

Use the data to interpret your map.

Weather map  symbols key examples

 

Atmospheric pressure. millibars (mb). Air pressure at sea level averages 1013 mb (14.7 lb./in2 or 1.04 kg/cm2 or 760 mm Hg or 29.92 in. Hg)

Wind speed. Each line represents 10 knots (kt) 1 kt = 1.5 mph = 1.8 kph) Short lines represent 5 knots. Add the lines to get the total air speed.

Wind direction. The circle represents the arrow head. The arrow points the direction the wind is blowing, but wind direction is referenced from the direction the wind is blowing. An arrow may point to the east and the wind is from the west.

Temperature is measured in degrees F every hour.

Dew point is the temperature in degrees F the air would have to be cooled to for the air to become saturated and for water vapor in the air to condense.

Cloud cover is the amount of the circle that is blackened. White = clear, All black is 100% covered, An X means the sky is obscured.

Present weather is illustrated with symbols

l One dot is intermittent rain

l l Two dots is continuous rain (light)

A triangle is hail

A triangle with a dot in it is sleet

* is intermittent snow

** Continuous snow (light)

, is intermittent drizzle

,, is continuous drizzle

Four crocked lines with an arrow is thunderstorm

= is fog

A triangle with a dot above the top edge is slight rain showers

A triangle with a line in the middle and a dot above the top edge is moderate or heavy rain showers

 

Many national forcast maps are available at NOAA

 

Resources

NOAA national weather service heat index temperature in degrees farenthiet

 

Heat index

 

Actual tracking data of a hurricane

 

Hurricane Andrew 16 - 28 August, 1992
Date and Time Latitude. degrees N Longitude degrees W Wind Speed knots
August 21 0000 23.2 62.4 45
0600 23.9 63.3 45
1200 24.4 64.2 50
1800 24.8 64.9 50
August 22 0000 25.3 65.9 55
0600 25.6 67 60
1200 25.8 68.3 70
1800 25.7 69.7 80
August 23 0000 25.6 71.1 90
0600 25.5 72.5 105
1200 25.4 74.2 120
1800 25.4 75.8 135
August 24 0000 25.4 77.5 125
0600 25.4 79.3 120
1200 25.6 81.2 110
1800 25.8 83.1 115
August 25 0000 26.2 85 115
0600 26.6 86.7 115
1200 27.2 88.2 115
1800 27.8 89.6 120
August 26 0000 28.5 90.5 120
0600 29.2 91.3 115
1200 30.1 91.7 80
1800 30.9 91.6 50
August 27 0000 31.5 91.1 35
0600      
1200      
1800      

 

For more information, maps & details for Andrew here at NOAA

 

 

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