What Does Life Cycle Assessment Have to Do with Global Warming?

Right now, you may be reading this article while wearing a shirt. When you bought it, you paid the sticker price. Long before that item reaches your hands, it leaves behind a hidden trail of drained water, heavy machinery energy, and carbon emissions.

We tend to judge an item's environmental footprint by how we use it, but the vast majority of its climate impact already happens miles away from store shelves.

The Hidden Impact of Everyday Items

Making truly sustainable choices is often more complex than it seems. Take a cotton T-shirt, for example. Before you wear it, a farmer grew the cotton, a factory processed it into fabric, a mill dyed it, and cargo ships carried it across global trade routes. Once you buy it, you wash and dry it dozens of times. Years later, you toss it out, where it ends up in a local landfill or incinerator.

Every single step in that chain releases greenhouse gases, the heat-trapping gases warming our planet. Focusing only on how much energy an item uses while in your home misses the vast majority of its real climate footprint. 

Buying a cotton T-shirt might feel like the lower-impact choice, and carbon-wise, it often is. An LCA measures a product’s Global Warming Potential (GWP)—how much heat it traps in our atmosphere compared to carbon dioxide (CO2e). An LCA study revealed a deeper insight where a garment is made can matter just as much as what it is made of. While energy-intensive fibers like Lyocell generally carry a higher carbon footprint than cotton within the same country, producing Lyocell in regions with cleaner energy mixes actually generates fewer emissions than producing a basic cotton shirt in a coal-dominant electricity grid. By measuring these competing factors—from regional power sources to land and water usage—an LCA ensures we look at the full picture instead of relying on oversimplified rules. 

What is Life Cycle Assessment (LCA) Actually?

This is where a Life Cycle Assessment (LCA) comes in—a tool sustainability experts use to map out these hidden impacts. Think of an LCA like a complete medical checkup for a product. Just as a doctor pinpoints an illness, an LCA diagnoses a product’s hidden environmental “hotspots”, revealing the stage where emissions or resource waste are at their worst.

Standardised internationally under ISO guidelines, an LCA tracks four main processes:

1. Extraction (Cradle): Pulling raw materials like oil, metal, or cotton out of the earth.

2. Manufacturing (Gate): Turning those raw materials into a finished product using factory energy.

3. Distribution & Use: Shipping goods across global supply chains and using them at home.

4. End-of-Life (Grave): Recycling, incinerating, or landfilling the product when it breaks.

Instead of guessing, an LCA gives precise numbers on a product’s Global Warming Potential (GWP), a term to measure how much heat a product traps in our atmosphere compared to carbon dioxide (CO2).

Looking Past the Label

Without an LCA, well-meaning decisions may backfire. An LCA measures these trade-offs so businesses and consumers do not accidentally trade one environmental problem for a worse one.

As global regulations tighten and markets around the world demand transparent carbon disclosures, relying on gut feelings or vague "eco-friendly" claims no longer cuts it.

How EPDs Give Products a "Nutrition Label"

Once a company completes an LCA, how do they show it to the public? They publish an Environmental Product Declaration (EPD).

Think of an EPD as a nutrition label for the environment. Just as a food label tells you the calories, fat, and sugar in a snack, an EPD tells you the exact carbon footprint, water use, and waste generated by a product.

When a factory or construction firm publishes an independently verified EPD, buyers can instantly compare two competing products and pick the more sustainable option based on scientific data.

By tracking products from cradle to grave using Life Cycle Assessment, we turn environmental problems into clear, solvable data points.

Science-based Informed Decision is Important

Global warming cannot be addressed through assumptions alone. It requires understanding where environmental impacts occur across the entire life cycle of products and services.

LCA provides organisations with a scientific framework to identify improvement opportunities, support informed sustainability decisions, and reduce environmental impacts. As expectations for climate action continue to evolve, adopting a life cycle perspective is becoming increasingly important for organisations seeking to create long-term environmental and business value.

LCI Can Support Your Sustainability Journey

Better sustainability decisions begin with better understanding.

At LCI, we help organisations apply Life Cycle Thinking through science-based solutions, including Life Cycle Assessment (LCA), Product Carbon Footprint (PCF), Environmental Product Declarations (EPD), and sustainability advisory. Backed by experience from 500+ LCA projects across diverse industries, we help organisations translate complex environmental data into practical strategies that support long-term sustainability goals.

Interested in learning more? We also offer tailored training programmes on Life Cycle Assessment (LCA), Product Carbon Footprint (PCF), and other sustainability topics to help organisations build internal expertise and confidently advance their sustainability journey.