Getting Started

The Earth is a dynamic system that transfers heat energy through convection, conduction, and radiation. This heat transfer, along with the energy from the sun , drives the weather on the planet.

In this section, students will discover how to measure how much energy the sun produces that reaches the Earth, how heat from the Earth's core reaches the surface, and how differences in air pressure means a storm is brewing.

Here are the scientific concepts:

  • Many phenomena on the Earth's surface are affected by the transfer of energy through radiation and convection currents.
  • The sun is the major source of energy for phenomena on the Earth's surface, powering winds, ocean currents, and the water cycle.
  • Solar energy reaches Earth through radiation, mostly in the form of visible light.
  • Heat from Earth's interior reaches the surface primarily through convection.
  • Convection currents distribute heat in the atmosphere and oceans.
  • Differences in pressure, heat, air movement, and humidity result in changes of weather.
  • The complex patterns of the changes and the movement of water in the atmosphere, determined by winds, landforms, and ocean temperatures and currents, are major determinants of local weather patterns.
  • Because these patterns are so complex, weather can only be predicted probabilistically.
  • The ocean exerts a major influence on weather and climate by absorbing energy from the sun, releasing it over time, and globally redistributing it through ocean currents.

By the end of the labs in this unit, students will be able to:

  • Know how to demonstrate how solar energy reaches Earth through radiation, mostly in the form of visible light.
  • Design and build an experiment that demonstrates convection currents.
  • Understand how to measure how much energy the sun produces.
  • Record data for atmospheric temperature, pressure, and humidity.
  • Differentiate observation from inference (interpretation) and know scientists’ explanations come partly from what they observe and partly from how they interpret their observations.
  • Measure and estimate the weight, length and volume of objects.
  • Formulate and justify predictions based on cause-and-effect relationships.
  • Conduct multiple trials to test a prediction and draw conclusions about the relationships between predictions and results.
  • Construct and interpret graphs from measurements.
  • Follow a set of written instructions for a scientific investigation.

Select a Lesson

Special Science Teleclass: Renewable & Alternative Energy
This is a recording of a recent live teleclass I did with thousands of kids from all over the world. I've included it here so you can participate and learn!Discover the world of clean, renewable energy that scientists are developing today! Explore how they are harnessing the energy of tides and waves, lean how cars …
Can a Battery Be Used to Store Energy?
A battery is a device that produces electrical energy from a chemical reaction. Another name for a battery is voltaic cell. Voltaic means to make electricity.Most batteries contain two or more different chemical substances. The different chemical substances are usually separated from each other by a barrier. One side of the barrier is the positive …
Can Insulation Save Energy?
An insulator is a substance that partly blocks or slows the flow of heat through it. Styrofoam is a lightweight plastic used in drinking cups. Styrofoam is a good insulator. A cooler or ice chest that is made of Styrofoam or some other insulator tends to block the flow of heat through it. Heat flows …
Can a Salt Be Used for Heating and Cooling?
Cooling and heating are opposite processes. Cooling is the removal of heat energy from an object or space and heating is the addition of heat energy to an object or space. We use these opposite processes a great deal in our daily lives. For example, in the kitchen we use the cooling provided by a …
How Can Shade Trees Keep Things Cool?
Having shade trees around a house can decrease the cost of cooling the house with air conditioning. A house not shaded from the sun absorbs some of the light from the sun and heats up the outside surface of the house. If the house is poorly insulated, some of this heat will penetrate into the …
Can the Evaporation of Water Be Used for Cooling?
The evaporation of water for cooling purposes is called evaporative cooling. An important example of this type of cooling is the removal of body heat by humans through sweating. When your body needs to cool, perspiration is released to the surface of your skin where it evaporates. The evaporation of the water in the perspiration …
Can Expanding Gases Be Used for Cooling?
In a typical air conditioning or refrigeration system, a liquid at high pressure is allowed to pass through a valve from a higher pressure to a lower pressure. As the liquid enters the lower pressure region, it changes from a liquid to a gas. This change causes a cooling effect. The liquid cools as it …
Can the Sun Be Used to Heat Water?
The energy of sunlight powers our biosphere (air, water, land, and life on the earth’s surface). About 50 percent of the solar energy striking the earth is converted to heat that warms our planet and drives the winds. About 30 percent of the solar energy is reflected directly back into space. The water cycle (evaporation …
How Can the Sun Be Used for Cooking?
Cooking involves heating food to bring about chemical changes. Sometimes foods are heated simply because the food tastes better warm than cold. In making tea, we sometimes heat water to help dissolve tea or help dissolve sugar if the tea is sweetened. Normally the water used to make tea is heated on a range top …
Can Solar Energy Be Concentrated?
The curved shape of the magnifying lens causes light rays to bend and focus on an image. When we look through the lens, we can use it to make writing or some other object appear larger. However, the magnifying lens can also be used to make something smaller. The light from the bulb is bent …
Can Electricity Be Made From Sunlight?
The solar cell you are using for this experiment is made from the element silicon. Silicon solar cells consist of two thin wafers of treated silicon that are sandwiched together. The treated silicon is made by first melting extremely pure silicon in a special furnace. Tiny amounts of other elements are added which produce either …
Can Water Be Heated With Composting Plant Material?
Fossil fuels, which include petroleum, natural gas, and coal, supply nearly 90 percent of the energy needs of the United States and other industrialized nations. Because of their high demand, these nonrenewable energy resources are rapidly being consumed. Coal supplies are expected to last about a thousand years. We must find other sources of energy …
Do Plants Store Energy?
A peanut is not a nut, but actually a seed. In addition to containing protein, a peanut is rich in fats and carbohydrates. Fats and carbohydrates are the major sources of energy for plants and animals. The energy contained in the peanut actually came from the sun. Green plants absorb solar energy and use it …
Can a Fuel be Made From Plant Material?
Yeast is a simple living organism that can break down sugars into ethyl alcohol (ethanol) and carbon dioxide. The process by which yeast breaks down sugars into ethyl alcohol and carbon dioxide is called fermentation. The tiny gas bubbles rising in the liquid mixture in the bottle are carbon dioxide gas bubbles that are made …
Atmospheres
Scientists do experiments here on Earth to better understand the physics of distant worlds. We’re going to simulate the different atmospheres and take data based on the model we use. Each planet has its own unique atmospheric conditions. Mars and Mercury have very thin atmospheres, while Earth has a decent atmosphere (as least, we like to …
How Much Energy Does the Sun Produce?
Without the sun, there would be no life on Earth. The sun warms the earth, generates wind, and carries water into the air to produce rain and snow. The energy of the sun provides sunlight for all the plant life on our planet, and through plants provides energy for all animals. The sun is like …
How Can Water Be Used to Store Heat Energy?
Temperature is a measure of the average hotness of an object. The hotter an object, the higher its temperature. As the temperature is raised, the atoms and molecules in an object move faster. The molecules in hot water move faster than the molecules in cold water. Remember that the heat energy stored in an object …
Can Wind Be Used as a Source of Energy?
The United States has large reserves of coal, natural gas, and crude oil which is used to make gasoline. However, the United States uses the energy of millions of barrels of crude oil every day, and it must import about half its crude oil from other countries. Burning fossil fuels (oil, coal, gasoline, and natural …
Cartesian Diver
Rene Descartes (1596-1650) was a French scientist and mathematician who used this same experiment show people about buoyancy. By squeezing the bottle, the test tube (diver) sinks and when released, the test tube surfaces. You can add hooks, rocks, and more to your set up to make this into a buoyancy game!
Instant Ice
Supercooling a liquid is a really neat way of keeping the liquid a liquid below the freezing temperature. Normally, when you decrease the temperature of water below 32oF, it turns into ice. But if you do it gently and slowly enough, it will stay a liquid, albeit a really cold one! In nature, you’ll find …
Hot Ice Sculptures
Did you know that supercooled liquids need to heat up in order to freeze into a solid? It’s totally backwards, I know…but it’s true! Here’s the deal: A supercooled liquid is a liquid that you slowly and carefully bring down the temperature below the normal freezing point and still have it be a liquid. We …
Cloud Tracker Weather Instrument
One of the most remarkable images of our planet has always been how dynamic the atmosphere is a photo of the Earth taken from space usually shows swirling masses of white wispy clouds, circling and moving constantly. So what are these graceful puffs that can both frustrate astronomers and excite photographers simultaneously? Clouds are frozen …
Thermometer
First invented in the 1600s, thermometers measure temperature using a sensor (the bulb tip) and a scale. Temperature is a way of talking about, measuring, and comparing the thermal energy of objects. We use three different kinds of scales to measure temperature. Fahrenheit, Celsius, and Kelvin. (The fourth, Rankine, which is the absolute scale for …
Hygrometer
Hygrometers measure how much water is in the air, called humidity. If it's raining, it's 100% humidity. Deserts and arid climates have low humidity and dry skin. Humidity is very hard to measure accurately, but scientists have figured out ways to measure how much moisture is absorbed by measuring the change in temperature (as with …
Anemometer
Most weather stations have anemometers to measure wind speed or wind pressure. The kind of anemometer we’re going to make is the same one invented back in 1846 that measures wind speed. Most anemometers use three cups, which is not only more accurate but also responds to wind gusts more quickly than a four-cup model. …
Barometer
A barometer uses either a gas (like air) or a liquid (like water or mercury) to measure pressure of the atmosphere. Scientists use barometers a lot when they predict the weather, because it’s usually a very accurate way to predict quick changes in the weather. Barometers have been around for centuries – the first one …
Rain Gauge
Also known as an udometer or pluviometer or ombrometer, or just plan old ‘rain cup’, this device will let you know how much water came down from the skies. Folks in India used bowls to record rainfall and used to estimate how many crops they would grow and thus how much tax to collect! These …
Desalination
This experiment is for advanced students. Lewis and Clark did this same experiment when they reached the Oregon coast in 1805. Men from the expedition traveled fifteen miles south of the fort they had built at the mouth of the Columbia River to where Seaside, Oregon now thrives. In 1805, however, it was just men …
Convection Currents
Every time I’m served a hot bowl of soup or a cup of coffee with cream I love to sit and watch the convection currents. You may look a little silly staring at your soup but give it a try sometime! Convection is a little more difficult to understand than conduction. Heat is transferred by …
Sensing Temperature
Temperature is a way of talking about, measuring, and comparing the thermal energy of objects.
Food Dye Currents
When something feels hot to you, the molecules in that something are moving very fast. When something feels cool to you, the molecules in that object aren’t moving quite so fast. Believe it or not, your body perceives how fast molecules are moving by how hot or cold something feels. Your body has a variety …
Making Clouds
Indoor Rain Clouds Making indoor rain clouds demonstrates the idea of temperature, the measure of how hot or cold something is. Here’s how to do it: Take two clear glasses that fit snugly together when stacked. (Cylindrical glasses with straight sides work well.) Fill one glass half-full with ice water and the other half-full with …
Soaking Up Rays
Heat is transferred by radiation through electromagnetic waves. Remember, when we talked about waves and energy? Well, heat can be transferred by electromagnetic waves. Energy is vibrating particles that can move by waves over distances right? Well, if those vibrating particles hit something and cause those particles to vibrate (causing them to move faster/increasing their …
Liquid Crystals
If you’ve completed the Soaking Up Rays experiment, you might still be a bit baffled as to why there’s a difference between black and white. Here’s a great way to actually “see” radiation by using liquid crystal thermal sheets. You’ll need to find a liquid crystal sheet that has a temperature range near body temperature …
Water Purification
Ever wonder how the water draining down your sink gets clean again? Think about it: The water you use to clean your dishes is the same water that runs through the toilet.  There is only one water pipe to the house, and that source provides water for the dishwasher, tub, sink, washing machine, toilet, fish …
Streaming Water
Fill the bathtub and climb in. Grab your water bottle and tack and poke several holes into the lower half the water bottle. Fill the bottle with water and cap it. Lift the bottle above the water level in the tub and untwist the cap. Water should come streaming out. Close the cap and the …
Sneaky Bottles
This experiment illustrates that air really does take up space! You can’t inflate the balloon inside the bottle without the holes, because it’s already full of air. When you blow into the bottle with the holes, air is allowed to leak out making room for the balloon to inflate. With the intact bottle, you run …
Squished Balloon
Fire eats air, or in more scientific terms, the air gets used up by the flame and lowers the air pressure inside the jar. The surrounding air outside the jar is now at a higher pressure than the air inside the jar and it pushes the balloon into the jar. Remember: Higher pressure pushes! Materials: …
Fountain Bottle
As you blow air into the bottle, the air pressure increases inside the bottle. This higher pressure pushes on the water, which gets forced up and out the straw (and up your nose!). Materials: small lump of clay, water, a straw, and one empty 2-liter soda bottle.
Ping Pong Funnel
As you blow into the funnel, the air under the ball moves faster than the other air surrounding the ball, which generates an area of lower air pressure. The pressure under the ball is therefore lower than the surrounding air which is, by comparison, at a higher pressure. This higher pressure pushes the ball back …
Magic Water Glass Trick
Where’s the pressure difference in this trick? At the opening of the glass. The water inside the glass weighs a pound at best, and, depending on the size of the opening of the glass, the air pressure is exerting 15-30 pounds upward on the bottom of the card. Guess who wins? Tip, when you get …
Hot Air Balloon
About 400 years ago, Leonardo da Vinci wanted to fly… so he studied the only flying things around at that time: birds and insects. Then he did what any normal kid would do—he drew pictures of flying machines! Centuries later, a toy company found his drawing for an ornithopter, a machine that flew by flapping …
Diaper Wind Bag
Lots of science toy companies will sell you this experiment, but why not make your own? You’ll need to find a loooooong bag, which is why we recommend a diaper genie. A diaper genie is a 25′ long plastic bag, only both ends are open so it’s more like a tube. You can get three …
Genie in a Bottle
While this isn’t actually an air-pressure experiment but more of an activity in density, really, it’s still a great visual demonstration of why Hot Air Balloons rise on cold mornings. Imagine a glass of hot water and a glass of cold water sitting on a table, side by side. Now imagine you have a way …
Soda Can Trick
When air moves, the air pressure decreases. This creates a lower air pressure pocket right between the cans relative to the surrounding air. Because higher pressure pushes, the cans clink together. Just remember – whenever there’s a difference in pressure, the higher pressure pushes. You will need about 25 straws and two empty soda cans …
Air Takes Space
You’re about to play with one of the first methods of underwater breathing developed for scuba divers hundreds of years ago.! Back then, scientists would invert a very large clear, bell-shaped jar over a diver standing on a platform, then lower the whole thing into the water. Everyone thought this was a great idea, until …
Squished Soda Can
An average can of soda at room temperature measures 55 psi before you ever crack it open. (In comparison, most car tires run on 35 psi, so that gives you an idea how much pressure there is inside the can!) If you heat a can of soda, you’ll run the pressure over 80 psi before …
Can Fish Drown?
If you’ve ever owned a fish tank, you know that you need a filter with a pump. Other than cleaning out the fish poop, why else do you need a filter? (Hint: think about a glass of water next to your bed. Does it taste different the next day?) There are tiny air bubbles trapped …
Special Science Teleclass: Solar Astronomy
This is a recording of a recent live class I did with an entire high school astronomy class. I’ve included it here so you can participate and learn, too! Light is energy that can travel through space. How much energy light has determines what kind of wave it is. It can be visible light, x-ray, radio, …
Solar Cookies
Can you use the power of the sun without using solar cells? You bet! We’re going to focus the incoming light down into a heat-absorbing box that will actually cook your food for you. Remember from Unit 9 how we learned about photons (packets of light)?  Sunlight at the Earth’s surface is mostly in the …
Marshmallow Roaster
Do you like marshmallows cooked over a campfire? What if you don’t have a campfire, though? We’ll solve that problem by building our own food roaster – you can roast hot dogs, marshmallows, anything you want. And it’s battery-free, as this device is powered by the sun. NOTE: This roaster is powerful enough to start …
Earthquakes!
When two blocks of the Earth slip past each other suddenly, that’s what we call an earthquake! From a physics point of view, earthquakes are a release of the elastic potential energy that builds up. Most energy is released as heat, not as shaking, during an earthquake. 90% of all earthquakes happen along the Ring …