The global worming category aggregates the greenhouse gas emissions into C02-equivalents in a 100 year perspective. For the reference scenario the total saved impact on
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global warming was found to be 322 kg C02-eq. per tonne of managed waste, in Fig. 3 we can see how a ±15% change in each component of the waste gives a variation in outcome for Case 1 between 14% more and 12% less savings than the reference scenario, and in Case 2 between 10% more and 10% less savings. Uncertainty ill waste composition has therefore a relatively large influence on the total impact from the system in this category. The most important fractions for both Case 1 and 2 are paper and plastic. A large paper fraction is impor¬tant for both the heating value of the waste to the incinerator and the favourable replacement of virgin paper production. While the C02-emissions from burning paper are counted as carbon neutral, the plastic is a non-renewable resource and the C02-emissions are accounted for in the total impact. More paper in favour of less plastic is therefore positive for tile total savings in impact in this category.