The Carbon Cycle

What is the Carbon Cycle?

By Luca (7th Grade)

The Carbon Cycle is a complex circle that shows how the world’s Carbon (Chemical Symbol: C, Atomic Number: 6) is transferred from form to form. The knowledge of this process is crucial to understanding Climate Change, and the Greenhouse Effect, on a whole new level.

Producers and um,

Photosinti-sintha-synthasesisis?:

It all starts with the Sun, which emits light and warmth into Earth's atmosphere. Some living things called producers capture the light in their tissues. Most of them are what we call plants. These plants also capture Carbon Dioxide (CO₂) from the atmosphere. They use the energy that they get from the light to break up the Carbon Dioxide molecules and use the Carbon, which is the C part of CO₂, to form long Carbon chains called glucose, or sugar. They use the sugars to form the tissues that capture the photons in the first place. When the Carbon is extracted, the plants release the excess Oxygen (Chemical Symbol: O, Atomic Number: 8) which is the O₂ part of CO₂. This process is called photosynthesis.

Consumers and Energy Switcheroos:

What happens to the Oxygen then? It gets released into the atmosphere, where other living things breathe it in. This category is called consumers, and they include animals, and humans as well. Some consumers also eat the sugars from the plants, and use the energy they get from the Oxygen to break apart the Carbon chains to get at the energy locked inside. They then use this energy to fuel their bodies. These are called herbivores. Other consumers eat other animals to get at the energy they have stored inside their bodies; and are called carnivores. Some consumers even do both, and are called omnivores. This process is called the Food Web. When the Carbon chains are broken, the excess Carbon is combined with the excess Oxygen from breathing to form Carbon Dioxide, which we breathe out along with any CO₂ or other useless gases we might have breathed in.

Earth’s Carbon and Random Atmospheric Gases like Krypton:

Together with the producers taking in Oxygen and releasing Carbon Dioxide, and the producers taking in Carbon Dioxide and releasing Oxygen, the Earth’s Carbon is relatively balanced between how much the plants take in, and how much the animals breathe out. However, throughout the Earth’s history, plants have been able to release a small amount more of oxygen than the animals can take in. This builds up over time, so today our atmosphere is about 78% Nitrogen, 21% Oxygen, 0.93% Argon, and <0.1% Carbon Dioxide. The rest is a hodgepodge of weird gases like Carbon Monoxide, Helium, Hydrogen, Krypton (no, not Kryptonite, which is not real, Krypton is a totally different thing that does not give you superpowers or take them away), Methane, Neon, Nitric Oxide, Ozone, Water Vapor, Xenon, you name it! But Oxygen is the 2nd most common gas in our atmosphere because of the producers. Thanks, plants!

Fossil Fuels and Zombie Plants:

But what happens to the Carbon chains inside the plants when they die? When land plants and microscopic plant-like plankton in the ocean die, the remains are buried under layers and layers of sediment that are deposited over millions of years. The sediment eventually hardens into stone, and the remains are crushed under the extreme pressure. The remains of the land plants are pressed into coal, and the plankton are pressed into oil (petroleum) and natural gas. These substances are called Fossil Fuels, because they are like fossils, not because Dinosaurs used them to run their cars. But, the Carbon chains and the energy they provide are still locked inside them.

How Humans Get Energy and Why Farting Cows are a Problem:

What happens to those Fossil Fuels? We humans dig them up and then burn them to get electricity that powers everything we do, from our lights to the computer I’m using to type this article right now. Liquid oil is even burned inside your car to fuel it! The problem is that burning Fossil Fuels breaks the Carbon chains locked inside them and releases the ancient Carbon Dioxide that these plants sucked in millions of years ago into the atmosphere. We humans also clear forests to make room for agriculture, and not only does burning trees release Carbon Dioxide into the atmosphere, but when the trees are gone, they can’t suck in any more Carbon Dioxide from the air. Another awful thing that we do is we keep millions, maybe even billions, of cows. This might not sound bad, but think about how much millions of cows must, um, let’s just say, pass gas. Farts are composed mainly of a gas called Methane, of which, given that there are millions of cows farting, a considerable amount leaks into the atmosphere.

Um, so What Does Any of This Have to do With Climate Change, and Why Should I Care?:

You should care because Carbon Dioxide and Methane are both potent greenhouse gases. greenhouse gases in the atmosphere are the main cause of human-induced Climate Change. To explain that, I’ll have to explain the Greenhouse Effect to you.

The Greenhouse Effect and What it Has to do With a Greenhouse:

I’m sure you have heard of the Greenhouse Effect, whether your level of recognition is “We’ve been studying this in Science Class, and I did my own private study to learn more about it” or “I heard my best friend mention it yesterday, but I have no idea what it means.” If you are in the second category, or have not heard of it all together, then I will explain it to you. To start, I will explain sunlight. The sun emits electromagnetic waves, which are a lot less complicated than they sound. These sunlight waves are made up mainly of photons, which are tiny sunlight particles that make up light and heat. They are also the same light particles that the producers take in. 51% of these photons are absorbed by the Earth, which then warms up. When the earth gets warm, it releases infrared light. Infrared is next to visible light in the light spectrum (see image), but, unlike Visible Light our eyes can’t see it. This infrared light is the heat of the earth, and it heads toward the edge of the atmosphere to escape. But the greenhouse gases (Methane and Carbon Dioxide, not to mention a few others like Water Vapor) capture that infrared light and bounce it back towards the earth. That means that the Earth warms up because of the extra heat. It’s sort of like a greenhouse, whose glass allows sunlight in, but doesn’t let the infrared light out, warming up the plants inside. Greenhouse gases aren’t bad in small amounts (actually, without them our planet would be well below 0 degrees Fahrenheit all the time), but humans have been putting so much into our atmosphere too quickly to be healthy for the Earth. Ice caps are melting due to the warmer arctic temperatures, and all that water means sea levels have been rising, and might start to flood coastal communities. Also, Climate Change can increase the number and severity of Natural Disasters like hurricanes, tornadoes, and wildfires.

The End, or is it?:

Well there you have it, the Carbon Cycle. This is how earth’s Carbon has been in balance between different forms over millions of years, and how humans are throwing it off balance like if someone much heavier than you sits on the other end of a see-saw. But it’s not over yet. There are lots of things that you can do to lessen the effects of Climate Change. You can plant a tree. You can buy Renewable Energy like Solar, Hydro, Wind, or Geothermal Power, instead of Fossil Fuels. And you can join groups like Climate Club DC who are devoted to making a real difference in our world.

GLOSSARY:

Argon -

A noble gas element (Chemical Symbol: Ar, Atomic Number: 18)

Atomic Number -

A number that each element on the periodic table has that shows the number of protons inside the atom.

Carbon -

An element of the periodic table (Chemical Symbol: C, Atomic Number: 6)

Carbon Cycle -

A cycle that Earth's Carbon goes through in different forms.

Carbon Dioxide -

A molecule made of one Carbon atom and two Oxygen atoms. It is a greenhouse gas.

Carbon Monoxide -

A toxic gas molecule that is made of one Carbon atom and one Oxygen atom.

Carnivore -

An animal that survives on mainly meat.

Chemical Symbol -

A letter or group of letters that defines an element no matter what language you speak. For example, Hydrogen = H, Helium = He, Lithium = Li.

CO2 -

The molecular name for Carbon Dioxide.

Coal -

A Fossil Fuel made from the remains of land plants. It is usually in the form of a black, chalky rock.

Consumer -

Any living thing that eats something else to survive.

Electromagnetic Waves -

Invisible waves of photon particles that make up light.

Food Web -

A system of which animals and plants eat other animals and plants.

Fossil Fuels -

Three substances made from ancient plant remains that are burned to make electricity.

Geothermal Power -

A form of Renewable Energy that involves sourcing heat from hot spots in the Earth's crust.

Glucose -

Sugars that plants make during photosynthesis. Glucose is essentially long chains of Carbon.

Greenhouse Effect -

A process in which greenhouse gases trap heat within the Earth's atmosphere.

Greenhouse Gases -

Gases that are able to reflect heat, such as Carbon Dioxide, Methane, and Water Vapor.

Helium -

A gas element in the periodic table (Chemical Symbol: He, Atomic Number: 2). It is used in balloons because it is only slightly heavier than Hydrogen and is non-flammable.

Herbivore -

An animal that survives on eating plant matter.

Hydrogen -

A gas element in the periodic table (Chemical Symbol: H, Atomic Number: 1), and the lightest element.

Hydro Power -

A source of Renewable Energy that harnesses the energy from moving water with a dam to turn it into electricity.

Infrared -

A type of invisible light (to the left of visible light on the light spectrum).

Krypton -

A noble gas element in the periodic table (Chemical Symbol: Kr, Atomic Number: 36) (Not to be confused with the mineral and planet from Superman)

Light Spectrum -

A system of measuring electromagnetic waves that defines different types of light/energy.

Methane -

A potent greenhouse gas that is made up of one Carbon atom and four Hydrogen atoms.

Natural Disaster -

A natural phenomena that endangers lives, such as a Hurricane or Tornado.

Natural Gas -

A type of Fossil Fuel that is burned for electricity, but is also used a lot in heating. It is extracted by way of Fracking.

Neon -

A noble gas element in the periodic table (Chemical Symbol: Ne, Atomic Number: 10). When electricity flows through it, it glows red-orange, and is used in Neon signs.

Nitric Oxide -

A molecule created by combining one atom of Oxygen and one atom of Nitrogen. It is a greenhouse gas.

Nitrogen -

An gas element in the periodic table, and the most common atom in the atmosphere (Chemical Symbol: N, Atomic Number: 7)

O2 -

The chemical name for molecular oxygen.

Oil -

A type of fossil fuel burned for electricity, but also used in tanks to power cars.

Omnivore -

An animal that survives by eating both plants and meat.

Oxygen -

A gas element in the periodic table (Chemical Symbol: O, Atomic Number: 8). It is also what most animals breathe.

Ozone -

A molecule created by combining three Oxygen atoms together.

Petroleum -

A synonym for Oil.

Photons -

Particles that make up Electromagnetic Waves.

Photosynthesis -

The process in which plants take in Carbon Dioxide, sunlight, and water, and produce Glucose and extra Oxygen.

Plankton -

Photosynthesizing microscopic ocean animals that give out 50% of our Oxygen.

Producer -

A living thing that produces its own energy using sunlight, water, and Carbon Dioxide.

Renewable Energy -

An energy source that does not run out, and does not contribute to Climate Change.

Sediment -

Mud and dirt carried by rivers that hardens into rock over time.

Solar Power -

A type of Renewable Energy source harnessing the power of the Sun.

Visible Light -

The Electromagnetic Wave types that we can see with our eyes.

Water Vapor -

The gas form of water (H2O).

Wind Power -

A type of Renewable Energy source harnessing the power of the wind.

Xenon -

A noble gas element in the periodic table (Chemical Symbol: Xe, Atomic Number: 54)