Carbon dioxide is the 4th most abundant component of dry air and the most abundant greenhouse gas. This means that CO2 is molecularly structured to capture and releasing heat throughout the atmosphere, much like the mirrors of a greenhouse.
While CO2 is produced naturally as part of the Earth’s carbon cycle, human activities and industrialization produce the vast majority of atmospheric CO2 in the Earth’s atmosphere today. For reference, human activities accounted for about 80% of all greenhouse gasses produced in 2019.
Read on for more details on the properties of CO2, where it comes from, and industrial data from the EPA.
What makes CO2 a greenhouse gas?
What separates CO2 as a greenhouse gas from any other gas is its ability to capture and release infrared energy. When the Sun’s light particles, a.k.a. photons, bumps into a CO2 molecule, the CO2 absorbs the photon’s energy.
This additional energy causes the CO2 molecule to vibrate and bump into other CO2 molecules which transfers that energy into the air surrounding it. Gas is typically measured by the molecular speed of the atoms in the air, so the faster and more frequently the CO2 molecules vibrate, the warmer the surrounding air becomes as they radiate infrared energy.
Again, greenhouse gasses are unique in their ability to capture and release infrared energy and not all gasses have this ability to capture and release infrared energy Like CO2. Gases like O2, N2, and H are not molecularly structured to capture energy on their own.
How is CO2 Produced naturally?
Depending on who you talk to, naturally produced CO2 might also be called biogenic emissions. On Earth, the most abundant sources of biogenic emissions come from forest fires, volcanic activity, and the byproduct of cellular respiration in animals.
These sources of CO2 are all components of the carbon cycle, the system which circulates carbon through chemical exchanges between Earth’s organisms, oceans, atmosphere, and soils. The carbon cycle is essential to sustaining life on Earth. For example, plants absorb airborne CO2, photons, and sugar molecules in a process called photosynthesis to generate the chemical energy need to produce new carbon-based plant cells. That carbon will be stored in the plant until it is eaten by another organism, combusted in a forest fire, or decomposed into the soil.
How do humans produce CO2?
Human sources of CO2, a.k.a anthropogenic emissions, come from The combustion of fossil fuels (coal, oil, and natural gas) and organic matter.
Here are a few human activities that emit CO2:
- Transportation
- Electricity generation
- Industrial manufacturing
- Deforestation
- Construction
Significant anthropogenic emissions can be traced back to the 18th century’s industrial revolution. This time in human history marks when civilizations began to shift from agriculturally dominated economies to more industrial economies powered by machine manufacturing.
These machines primarily relied on coal, oil, or steam, which was a byproduct of burning coal. The first combustion engines followed soon after and were eventually made affordable enough for the working class to own. From the industrial revolution to the present day, concentrations of atmospheric CO2 have experienced parabolic growth.
For comparison, concentrations of atmospheric CO2 were around 270ppmv. After the industrial revolution, that number has risen to 400ppmv. At the time of this article, the concentration of CO2 is now 409ppmv.
Which industries produce the most greenhouse gas?
The EPA has publicly available greenhouse gas inventory data from over 8,000 US companies. According to their data, the top 5 industries that emit the most carbon are:
- Petroleum Product Suppliers
- Power Plants
- Metal and mineral refineries
- Chemical treatment plants
- Waste and landfills
The industrial sector that emits the most CO2 belongs to the power plants and petroleum product suppliers category. On average, these companies produce about 7232854.09 Mega Tonnes of CO2 per year
That’s the equivalent of running your car on the highway for 32,194 years and 339 days.
Or it would take the entire US population 0f 328.2 million people a little over 13 years to burn that much fuel via car.
