Greenhouse Gases
Where they come from, where they go, and how they cause climate disasters.
The gist of it
🥵 Greenhouse gas emissions heat up the air, land, and oceans, causing climate disasters — from catastrophic floods in Pakistan and Puerto Rico to heat waves in California and China.
⛽️ The vast majority of greenhouse gas emissions come from burning fossil fuels.
🌞 We can’t derail the impacts of climate change without transitioning away from fossil fuels, and that only happens with systemic change.→ Estimated reading time: 8 minutes
What are greenhouse gases?
Greenhouse gases are a critical climate metric. If there was a climate change scoreboard, greenhouse gas emissions would be the points. Even though greenhouse gases make up less than 0.1% of Earth’s atmosphere, this small slice of the atmospheric pie has caused a drastic, global shift in temperatures.1
Greenhouse gases (GHGs) come from various sources, but most come from human activities — mainly, burning fossil fuels. When GHGs take up occupancy in the atmosphere, land, and oceans, they capture and emit heat for decades (or even centuries).
Carbon dioxide makes up nearly 80% of human-made greenhouse gases. Here are the main GHGs contributing to climate change2:
Carbon dioxide (CO₂)
Nitrous oxide (N₂O)
Methane (CH₄)
Chlorofluorocarbons (CFCs)
🔥 Hot tip: Because carbon dioxide is the most abundant greenhouse gas, other GHG measurements are often converted to a CO₂ equivalent. Where do greenhouse gases come from? (Or, Why we can’t talk about emissions without talking about fossil fuels)
Way back in the day, emissions were a more balanced give-and-take:
🌱 Plants consumed carbon from the atmosphere.
🐿 Animals ate the plants.
🪦 Animals and plants decomposed, releasing carbon emissions in the air.
🔁 Repeat, repeat. It’s the circle of life 🦁.
But burning fossil fuels (coal, gas, and oil) has drastically thrown off that balance, releasing emissions at a breakneck pace. The more fossil fuels we use, the more GHGs we emit. In the past decade, fossil fuels were the cause of around 89% of our greenhouse gas emissions. [Fig. A]
Just 20 oil companies were responsible for 35% of global carbon dioxide and methane since 1965.
😤 Not-so-fun fact: BP (British Petroleum) coined the term "carbon footprint" in 2004 as part of a marketing plan to pass the responsibility of emissions onto consumers. 
GHGs from burning fossil fuels:
🚗 Transportation: cars, buses, boats, trains, and planes
🏠 Temperature control: space heating, water heating, air conditioning, refrigeration, and cooking
💡 Lighting in residential and commercial buildings
🏭 Manufacturing and machinery, aka the energy required to make food and products.
🛢 Methane and other leakage from “producing” fossil fuels: oil, coal, and gas
GHGs that aren’t directly from burning fossil fuels:
🪓 Deforestation and crop burning for food production (agriculture and livestock grazing).3 Trees and forests — key tools for carbon capture — are replaced with agriculture that requires fertilizers and gas-powered machinery.
📈 Synthetic fertilizers produce nitrous oxide when added to soil.4
🐄 Gas and manure from cows and other livestock (Cow burps!)
🗑 Waste emissions from landfills, combustion, and wastewater treatment.
🪨 Making cement surprisingly makes up around 8% of global emissions.
How are greenhouse emissions measured?
Emissions are often measured by weight in metric tons (aka tonnes). One metric ton = 2,204 pounds. It’s hard to imagine how much space 2,204 pounds of gas takes up, but if you wanted to fill a balloon with CO₂ until it weighed 1 metric ton, you’d need a 33ft balloon [Fig. B].
Now that we can picture a metric ton of CO₂, let’s get some context on personal emissions impact. If you strapped a 33ft balloon onto the tailpipe of your Camry and drove 10 miles a day, you’d fill up the balloon with CO₂ about once per year.
Let’s zoom out to see how your Camry CO₂ balloon compares to some big businesses:
👚 ASOS filled over 27 balloons every hour in 2019.*
🥤 Coca-Cola filled over 10 balloons every minute in 2021.
🛢 ExxonMobil filled over 24 balloons every second in 2020.
On average, each person in America emitted ~14 metric tons of CO₂ in 2020 — that’s twice as much as each person in China. Still, it would take one American 18 months to rack up the amount of greenhouse gases that ExxonMobil emits in one second.
That’s why systemic shifts away from fossil fuels — in companies, cities, and countries — can make a bigger impact than personal changes.
*This metric is based on the ASOS Carbon Report (p.24), but it’s worth noting that measuring emissions in the fashion industry is difficult and opaque.
How do greenhouse gases affect temperatures?
Greenhouse gases were in Earth’s atmosphere long before humans. But when we started burning fossil fuels for things like electricity and transportation, we started emitting high volumes of GHGs much faster than people, plants, or animals could absorb them, causing a massive GHG buildup.
With more GHGs comes more heat. Greenhouse gases keep more heat on Earth and slow the release of heat out into space.5 Here’s an approximate breakdown of where greenhouse gases go6:
☁️☁️☁️☁️☁️☁️☁️☁️☁️☁️ ~50% go into the atmosphere
🌳🌳🌳🌳🌳 ~25% go into plants and soil
🌊🌊🌊🌊🌊 ~25 go into oceans
🤯 Each gas has a different lifespan, but carbon dioxide stays in our atmosphere for 300-1,000 years! That means that emissions from the Titanic boiler room — where Rose and Jack gleefully gallivanted — those are still in the atmosphere.
Here are some effects of the atmosphere warming:
🥵 Extreme heat is deadly — it’s the deadliest severe weather in the world.
🌵 More drought because hot air absorbs more moisture from soil and plants.
⛈ Extreme rain, flooding, and storms due to more water vapor in the hot air.
🔥 Wildfires start more easily without consistent rain.
🛒 Food shortages from drought-ridden crops and dire working conditions.
Greenhouse gas emissions aren’t just heating up the atmosphere — they’re heating up the oceans too. Oceans absorb 1/3 of humans' CO₂.7 To try and regulate water temperatures, oceans release some heat by evaporating water, melting ice, reheating the atmosphere, or putting GHGs into mysterious underwater reservoirs.8
Oceans are the largest carbon sink on the planet — meaning they absorb more carbon than they release. But with enough greenhouse gas buildup over time, they could become carbon emitters 🤯.
Here are some effects of oceans warming:
🌊 Sea levels rise because water expands when it’s heated.
🌪 More cyclones, hurricanes, and typhoons due to warming waters.
🏚 Disastrous flooding, especially on islands and in coastal communities.
🐟 Dying sea life and coral reefs due to an increase of greenhouse gases.
Where are all these emissions coming from? And where are they having the biggest effect?
Geographically, the five countries with the most total emissions are the US, China, Russia, Germany, and the UK. But these are not the countries experiencing the most dire effects of their own emissions.
Instead, the past decade has left these countries paying the highest price of climate change with their lives and livelihoods: Puerto Rico, Myanmar, Haiti, Philippines, Mozambique, Bahamas, Bangladesh, Pakistan, and Thailand.9
But cumulatively, those 9 at-risk countries have only added 1.08% to our global greenhouse gas emissions 10:
🇺🇸 25% US
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🇨🇳 14% China
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🇷🇺 7% Russia:
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🇩🇪 5% Germany
▋▋▋▋▋▋
🇬🇧 5% United Kingdom
▋▋▋▋▋
🚩 1% The 10 countries most affected by extreme weather events
▋
Compare the map of cumulative greenhouse gas emissions to the map of global risk. You can see that many of the countries pumping out the most greenhouse gases are not the ones dealing with the most disastrous effects. In some areas, the two maps even look inverted. [Fig. D]
How can we lower greenhouse gas emissions?
Most GHG emissions come from fossil fuels, so burning less of them is a critical way to lower greenhouse gas emissions. Fossil fuels are so ingrained in our economies that the transition away from them can’t happen without systemic change.
🗺 Global systems: The final agreement of the 2021 UN Climate Change Conference mentioned fossil fuels for the first time since the 90s. This vague goal to phase down coal was met with a lot of pushback, especially from more vulnerable countries experiencing a higher death toll from climate disasters.
🇺🇸 US systems: The new Inflation Reduction Act is the biggest climate bill that’s ever passed in the US. It aims to drive down reliance on fossil fuels with $369 billion to fund a decade of incentives for businesses and residents to transition to more clean energy. It’s forecasted to bring pollution down to 2005 levels by 2030.11
But the bill also includes perks for fossil fuel companies like tax credits for carbon capture and new allowances for offshore drilling. There are also financial penalties like fees for methane leaks and drilling on federal land.
My last two cents on greenhouse gas emissions:
¢ Advocate and act on plans to lessen your company, city, and country’s systemic reliance on fossil fuels.
¢ Scrutinize any and all sustainability marketing, especially from fossil fuel companies. Look for stats and context.
As climate change disasters become more frequent and catastrophic, oil companies and other big emitters are going to release more ads with images of immaculate forests, oceans, and palms cupping seedlings. But if the past couple centuries have taught us anything, it’s that we won’t derail climate change without transitioning away from fossil fuels.
Next month, I’m diving into fossil fuels! If you have questions you’d like answered, let me know.
✅ Corrections & suggestions 🧮 Check my math 📊 Sources & stats 📸 Instagram
Neato resources
EPA Power Profiler: See what type of energy each US state uses
Database of State Incentives for Renewables & Efficiency (US)
Ballotpedia’s Energy on the Ballot: An aggregate of US energy ballot measures
Eco-Bot.Net scrapes and analyzes social media ads paid for by big polluters