BY GAUTAM RAMCHANDANI| APRIL 21, 2025 | Sustainability : The Fight Against GHGs
The climate crisis facing the world today is not a natural anomaly—it is the direct result of human activity. Since the dawn of the Industrial Revolution in the 1760s, the concentration of greenhouse gases (GHGs) in Earth’s atmosphere has steadily increased, driven by fossil fuel combustion, deforestation, and industrial growth. This surge in emissions has intensified the planet’s natural greenhouse effect, accelerating global warming and destabilising the climate systems we depend on.
But the truth is, greenhouse gases are not inherently bad. In fact, they’re essential to life on Earth. It’s the excess of these gases that poses a problem.
Understanding the Greenhouse Effect
The greenhouse effect is a natural phenomenon that makes life on Earth possible. Greenhouse gases like carbon dioxide (CO₂), water vapour, methane (CH₄), and nitrous oxide (N₂O) act like the glass of a greenhouse—allowing sunlight to enter the atmosphere and reach Earth’s surface, while trapping some of the heat that radiates back into space. This process keeps the planet warm enough to sustain life.
Without the greenhouse effect, Earth’s average surface temperature would plummet to a frigid -20°C, making it inhospitable to humans, animals, and plants. Greenhouse gases are crucial for processes like photosynthesis (carbon dioxide) and precipitation (water vapour), and they enable Earth’s climate to remain stable—when in balance.
When Balance Turns to Imbalance
The problem isn’t the greenhouse effect itself—it’s that human activities are disrupting it. Imagine wrapping yourself in one warm blanket on a cold night—cozy, right? But now, picture piling on five more or ten more. Suddenly, it’s stifling.
Now Imagine the Earth wrapped in a blanket that keeps it warm, and we keep piling on blanket after blanket. That’s what’s happening as GHG concentrations rise: more heat is trapped, and less is released, pushing global temperatures upward.
Ecosystems and species are struggling to adapt, to this rapid heating, leading to biodiversity loss, shifting weather patterns, rising sea levels, and extreme climate events. This is no longer a distant threat—it’s already happening.
The contribution of each greenhouse gas to climate change depends on three factors: How much of it is in the atmosphere, How long it stays thereHow effectively its traps heat.
Naturally Occurring Greenhouse Gases
Water Vapour (H₂O):
The most abundant GHG, it increases as the Earth warms, intensifying the greenhouse effect. However, its concentration is largely a result of temperature changes, not direct emissions from human activity.
Carbon Dioxide (CO₂):
Naturally released through respiration, volcanic activity, and decay of organic matter. Human activities—especially the burning of fossil fuels—have made CO₂ the primary driver of the enhanced greenhouse effect.
Methane (CH₄):
Emitted from wetlands and decaying matter, but also from human sources like livestock, landfills, and fossil fuel extraction. Methane is significantly more efficient than CO₂ at trapping heat, although it remains in the atmosphere for a shorter time.
Nitrous Oxide (N₂O):
Generated by soil bacteria and enhanced by synthetic fertilisers, fossil fuel combustion, and industrial activity. It is highly potent and lingers in the atmosphere for over a century.
Ozone (O₃):
While protective in the upper atmosphere, ozone in the lower atmosphere acts as a greenhouse gas and air pollutant, contributing to both warming and poor air quality. However O₃ typically dissipates within a few hours to a few days.
Anthropogenic Greenhouse Gases: The Human Contribution
Human-generated emissions, also known as anthropogenic greenhouse gases, are the main cause of climate change today. Let’s break down the major contributors:
Carbon Dioxide (CO₂): The Main Offender
Carbon dioxide remains the largest contributor due to its widespread release from burning coal, oil, and natural gas. Deforestation also plays a major role, as forests and peatlands that once absorbed CO₂ are being cleared or degraded, releasing their stored carbon. In fact, about 13% of current global carbon emissions are linked to tropical deforestation.
- Methane (CH₄): Small But Mighty
Methane is the second largest driver, responsible for around 16% of human-caused emissions. Though its concentration is lower, methane traps 72 times more heat than CO₂ over a 20-year period, making its impact disproportionately large. Human activity, particularly in agriculture and waste management, has greatly increased methane emissions.
- Nitrous Oxide (N₂O): The Silent Force
Nitrous oxide (laughing gas) accounts for around 6% of human-caused greenhouse gas emissions and is largely produced from synthetic fertilisers, fossil fuel burning, and industrial processes. It is even more potent than methane and stays in the atmosphere for more than a century, with one tonne of N₂O equaling the warming impact of 310 tonnes of CO₂ over a century.
- Fluorinated Gases (F-gases): The Synthetic Super Pollutants
Additionally, synthetic fluorinated gases—such as hydrofluorocarbons (HFCs), per-fluorocarbons (PFCs), and sulphur hexafluoride (SF₆)—make up a small but dangerous percentage of emissions. These gases are used in refrigeration, electronics, and various industrial processes. While they account for only around 2% of emissions, their global warming potential is thousands of times greater than carbon dioxide, and they can remain in the atmosphere for centuries.
Measuring and Mitigating GHG Emissions
Addressing greenhouse gas emissions is not simple, but essential, it requires a comprehensive approach from global policy makers to local actions, from corporate responsibility to individual choices.
All sectors, government, business, and individuals, have to play a role. Businesses, in particular, must adopt robust environmental, social, and governance (ESG) frameworks and aim to reduce emissions across all levels. This includes direct emissions (Scope 1), emissions from purchased energy (Scope 2), and indirect emissions from supply chains and consumers (Scope 3). Companies must commit to sustainable practices like switching to renewable energy, improving energy efficiency, embracing circular economy models, and prioritising responsible sourcing.
Innovation will be key in tackling emissions. Technologies such as carbon capture and storage (CCS), direct air capture (DAC), and biochar offer promising ways to remove carbon dioxide directly from the atmosphere. In agriculture, regenerative practices like cover cropping, reduced tillage, and rotational grazing not only reduce emissions but also improve soil health and resilience. These solutions must be scaled quickly to meet the urgency of the climate crisis.
The greenhouse effect gave us a planet we could live on. Now its up to us to restore the balance and protect our only home from the consequences of our disruption. We need science-based targets, transformative innovation, and widespread strategic collaboration to transits from being the cause of climate change to becoming the solution.
The time for action is now—before the planet’s warming becomes irreversible.