Uncertainty Analysis for the Computation of Greenhouse Gas Concentrations in IMAGE

Uncertainties in simulations of greenhouse gas concentrations are analyzed. Greenhouse gas concentrations are simulated using the Atmospheric Composition model of IMAGE. Uncertainties arise from, amongst others, uncertainties in greenhouse gas emissions and in parameters in the description of atmospheric processes. The total uncertainty in the greenhouse gas concentrations is quantified as well as the contributions of the individual sources of uncertainty to this total uncertainty, by making a multi-dimensional Monte Carlo analysis using Latin Hypercube sampling. Focus is on the non CO2 gases like methane and ozone, for which atmospheric processes play a key role in determining the changes in concentration.