> ## Documentation Index
> Fetch the complete documentation index at: https://docs.greenzero.eu/llms.txt
> Use this file to discover all available pages before exploring further.

# Global Warming Potential (GWP)

> Understanding Global Warming Potential (GWP) in GREENZERO Journey LCA

<Info title="PEF naming">
  In the PEF method this category is called **Climate change**. It measures the same greenhouse gas
  emissions and also uses the unit **kg CO₂ eq**. The difference is only in terminology and does not
  affect calculations.
</Info>

## Definition

Global Warming Potential (GWP) measures the amount of heat trapped in the atmosphere by a greenhouse gas relative to carbon dioxide (CO₂). It is expressed in kilograms of CO₂ equivalent (kg CO₂ eq.) using ReCiPe 2016 characterization factors.

## Environmental Mechanism

Greenhouse gases (GHGs) such as carbon dioxide (CO₂), methane (CH₄), and nitrous oxide (N₂O) trap heat in the Earth's atmosphere, leading to global warming and climate change. Each GHG has a different capacity to trap heat and remains in the atmosphere for different periods.

The main environmental effects of increased GWP include:

* Rising global temperatures
* Sea level rise
* Increased frequency and severity of extreme weather events
* Changes in precipitation patterns
* Ocean acidification
* Biodiversity loss
* Agricultural impacts

## Calculation in GREENZERO Journey

GREENZERO Journey calculates GWP by:

1. Identifying all greenhouse gas emissions associated with a product throughout its lifecycle
2. Converting each gas to its CO₂ equivalent using characterization factors from ReCiPe 2016
3. Summing all CO₂ equivalents to determine the total GWP

<Info>
  **About ReCiPe 2016**

  ReCiPe 2016 is a life cycle impact assessment (LCIA) method that provides characterization factors for converting inventory data into environmental impact indicators. It is not a methodology itself, but rather a comprehensive database of impact assessment factors developed by Dutch research institutes.

  The method provides characterization factors that translate emissions and resource use into standardized impact units (e.g., kg CO₂ eq. for climate change, kg SO₂ eq. for acidification). GREENZERO Journey follows ISO 14040/44 methodological standards while using ReCiPe 2016 characterization factors for impact calculations.
</Info>

## Environmental Cost Conversion

The GWP impact is converted to environmental cost using the CE Delft cost factor:

**CE Delft Cost Factor for GWP: €0.13 per kg CO₂ eq.**

This factor represents the societal cost of damage from climate change, including:

* Economic damage from sea level rise
* Agricultural losses
* Human health impacts
* Extreme weather events
* Biodiversity loss

## Example Calculation

For a product with a GWP of 10 kg CO₂ eq. per piece:

```
Environmental Cost = GWP × CE Delft Factor
Environmental Cost = 10 kg CO₂ eq. × €0.13/kg CO₂ eq.
Environmental Cost = €1.30 per piece
```

## Interpretation

GWP is often the most recognized environmental impact category and frequently dominates the total environmental cost of products. Key contributors to GWP in product lifecycles typically include:

* Energy consumption (especially from fossil fuels)
* Transportation emissions
* Agricultural processes (particularly for food products)
* Chemical manufacturing processes
* Waste management emissions

## Reduction Strategies

Common strategies to reduce GWP include:

* Energy efficiency improvements
* Renewable energy sourcing
* Material reduction or substitution
* Process optimization
* Transportation mode shifts
* Carbon offsetting (as a last resort)

## Data Quality Considerations

When interpreting GWP results, consider:

* Data age and geographic relevance
* System boundary definitions
* Allocation methods used
* Uncertainty in emission factors

## Related Impact Categories

GWP often correlates with other impact categories, particularly:

* Photochemical Ozone Creation Potential
* Acidification Potential
* Fossil Resource Depletion

## References

* [IPCC Sixth Assessment Report Synthesis](https://www.ipcc.ch/report/ar6/syr/)