Everyone Should Understand The Carbon Cycle

Carbon capture is a critical sector required for global decarbonization. (Image: Envato)
Carbon capture is a critical sector required for global decarbonization. (Image: Envato)

Earth’s burning. Literally. And finally, we are beginning to see large swaths of our population turn their heads towards the threat of increasingly obnoxious global warming and begin to ask what they can do to help. The best way that I think I can add value is by helping address one of climate change’s most time-sensitive variables: the atmospheric oversaturation of carbon dioxide. When I brightly proclaim my aspirations to have a career in this less popular Earth-saving field called carbon capture, I’m most often met with blank stares and uncomfortable chuckles as if I’ve suddenly started speaking in tongues. So, I’ll usually give a quick explainer: “our skies are already oversaturated with carbon dioxide and other harmful particulates, and it’s crucial to suck as much of it out as we can ASAP to survive climate change.

What has really fascinated me is that the second reaction I’m met with most often is: “Well, what about the trees? Can’t we just plant more trees?”  

I usually struggle at this point with how to articulate a neat description of the practical and scientific reasons why a mass effort to plant trees will not simply solve this issue, or whether I should just scream “NO” and find the nearest bag to hyperventilate into. The global warming puzzle we now must solve is complex. Many of its pieces are wrought out of fires that we have forged ourselves. Others are linked to the very fabric of the natural world and its codependent ecosystems.

Carbon capture, an essential tool that’s finally starting to receive the attention it deserves as a necessity to combat climate change, is still a field that much of the population does not understand. Even without the heavy touch of humanity-induced climate change, capturing carbon atoms is still a pivotal component of Earth’s interconnected carbon cycle. It works well independently and can put up with a moderate number of unasked contributions. Understanding how Earth did it before we came around messing up the balance and needing more aggressive means to control our pollution propensity is the first step to appreciate why we should really all become some type of tree hugger.

The Earth & Atmosphere's Operational Relationship with Carbon

The Science Behind the Cycle

To appreciate the impact of trees, one has to first understand what their role is in the big picture of Earth’s normal operations. So, let’s talk about the carbon cycle. On the most basic level, photosynthesis (CO2 absorption) and respiration (CO2 release) are the two fundamental processes involved in exchanging carbon atoms between Earth’s atmosphere and its terrestrial biosphere (aka land-based vegetation). Through the process of photosynthesis, plants emit oxygen and store carbon to become what we call a carbon sink. Respiration provides what’s known as a carbon source. The oldest, expected emitters are animals and slain/decaying plants. However, older and larger concentrations of carbon, previously undisturbed until human intervention, have become a more venerable carbon source. Our impact has been so significant that we’ve even given our pollution contribution from human activities its own name: anthropogenic carbon emissions. In the past 80,000 years, the planet hasn’t seen anywhere near as high a concentration of particles in the atmosphere as there are right now.

The Scourge of Anthropogenic Emissions

The carbon cycle does the best that it can to balance the massive excess of carbon atoms we’ve been emitting. The terrestrial biosphere absorbs approximately one-fourth of anthropogenic CO2 emissions annually. The ocean absorbs another fourth, and the remaining half of our emissions remain in the atmosphere. While there are many other polluting particulates, COis a favorite to focus on because it accounts for the highest percentage of emissions at about 80% and has been proven to be the key gas that sets the Earth’s temperature. It stays in the atmosphere for the longest period of time(scientists estimate this lifespan to be between 300 and 1,000 years), and hotboxes the Earth by trapping heat that would otherwise escape and re-emitting it back down to us.  

A resounding theme we can see in nature from a macro to subatomic particle level is an innate propensity for homeostasis. Without our help or knowledge, our planet has already figured out many clever mechanisms that it deploys to create its own checks and balances system. When temperatures rise, the rate of photosynthesis and respiration naturally increase. However, at the aptly named climate tipping point, this balance is predicted to cease. At this point of atmospheric oversaturation, although the rate of respiration will continue to function normally, photosynthesis will begin to decline. So, as the scales become imbalanced, we’ll find that we all have much less oxygen to go around.


Measuring carbon levels is important because it is our planet’s natural thermometer. Earth’s atmosphere regulates temperature and will respond to extreme imbalances much like how the human body does once it reaches an internal temperature of around 104°F (40°C): the major organs that give us life will begin to break down. At 107°F (41.67°C), the body’s most likely not going to bounce back. Scientists have determined that after the Earth’s temperature rises past 2°C (which is expected to happen by the end of this century), the planet will experience a similar phenomenon. We’re currently predicted to hit the 1.5°C marker by 2030, so expect even bigger, more dramatic changes on the murky, clogged horizon.

The doomsday level temperature increase is equivalent to a rise in the atmospheric concentration of CO2 of between 425-450 parts per million (ppm). Before humanity went all-in for fossil fuels, preindustrial levels of carbon dioxide were 280 ppm. According to NASA’s James Hansen, a top climate scientist, the “safe” upper limit was really 350 ppm. Earth, by herself, needed 20,000 years to go from 185 ppm to that preindustrial 280 level measured in 1850. According to Hansen’s op-ed, at 550 ppm, we’d reach catastrophic temperatures previously last seen when sea levels were 80 feet higher. So, we all have that to look forward to, too.

According to CarbonTracker, the global monthly mean of anthropogenic emissions sitting in the atmosphere was 416.49 ppm as of May of this year. Overall, the data shows an easy to interpret summary: the concentration of particulates in our atmosphere is consistently still on the rise every single year.

With this newfound appreciation of the carbon cycle’s importance in keeping our planet cool, we can see how and why our pollution propensity is pulling us towards catastrophic climate change. There is an urgent need to start pulling as much carbon out of the atmosphere as possible. Now begins our tree-hugging trekk to appreciate why we must both plant and protect trees, and deem the strength of their role as a carbon sink. For the sake of simplicity, this series will only examine the tree-related variables helping and hindering our progress to dial back Earth’s rising fever.

About The Author

Stephanie Zulman

Stephanie Zulman

Partner • Editor-in-Chief @ The Impact

Stephanie holds a BBA in Supply & Value Chain Management and in Entrepreneurship & Innovation from TCU (Go Frogs!!) and minored in both Energy and History because… why not. After a stint in LA working in lean manufacturing for a large industrial company, her most recent educational foray was as a part of the LEAP program at Boston University to explore the field of Material Science & Engineering. Stephanie’s most recent work has been volunteering with a small DAC startup in Reykjavik called Carbon Iceland. Now, she’s living the dream working in supply chain as a Procurement Analyst at the carbon capture company, LanzaTech. An aspiring tree hugger, she hopes to spend the rest of her career aiding the massive societal transition to cleaner industrial and business practices– ideally through work pertaining to carbon capture, sequestration, and the processes’ byproduct utilization to unite her love of science, sustainability, business, and supply chain. In her free time she enjoys both the American and English versions of football, growing her working knowledge of plant cultivation, and reading.

Share this post →


A weekly newsletter helping climate founders and investors discover undercover climate startups, technologies and opportunities before everyone else. Written by founders, executives and investors with years across the climate-tech space. Subscribe for free today to grow your climate positive impact.

Related posts...

Discover Pre Series-A Climate Startups Weekly

Develop your market map of up-and-coming climate startups and market opportunities by subscribing to our weekly newsletter for free.