GWPværdier

GWPværdier, standing for Global Warming Potential values, are a crucial metric used to quantify the climate impact of different greenhouse gases. These values represent how much heat a greenhouse gas traps in the atmosphere over a specific time period, compared to carbon dioxide (CO2). CO2 is used as the baseline, with a GWPværdier of 1.

Gases with higher GWPværdier contribute more significantly to global warming per unit mass. For example, methane (CH4) has a GWPværdier of 28-36 over 100 years, meaning it traps 28 to 36 times more heat than CO2 over that period. Nitrous oxide (N2O) has a GWPværdier of 265-298 over 100 years.

The time horizon used is important; GWPværdier are typically reported for 20, 100, and sometimes 500 years. Shorter time horizons capture the more potent, immediate warming effects of gases like methane, which are less persistent in the atmosphere than CO2. Longer time horizons reflect the cumulative warming over extended periods.

These values are essential for greenhouse gas inventories, climate modeling, and the development of climate policies and regulations. They allow for a standardized comparison of the warming impact of various gases, enabling policymakers to prioritize mitigation efforts and track progress towards climate targets. Understanding GWPværdier helps in calculating the "CO2 equivalent" emissions of a mixture of gases, providing a single number to represent the overall climate forcing.