GREENHOUSE-EFFECT OF NOX

Through various processes the nitrogen oxides (NO,) interact: with tra ce gases in the troposphere and stratosphere which do absorb in the sp ectral range relevant to the greenhouse effect (infrared wavelengths). The net effect is an enhancement of the greenhouse effect. The cataly tic role of NO, in the production of tropospheric ozone provides the m ost prominent contribution. The global waming potential is estimated a s GWP (NOx) = 30 - 33 and 7 - 10 for the respective time horizons of 2 0 and 100 years, and is thereby comparable to chat of methane. NO, emi ssions in rural areas of anthropogenically influenced regions, or thos e in the vicinity of the tropopause caused by air traffic, cause the g reenhouse effectivity to be substantially more intense. We estimate an additional 5 - 23 % for Germany's contribution to the anthropogenic g reenhouse effect as a result of the indirect greenhouse effects stemmi ng from NO,. Furthermore, a small and still inaccurately defined amoun t of the deposited NO, which has primarily been converted into nitrate s is again released from the soil into the atmosphere in the form of t he long-lived greenhouse gas nitrous oxide (N2O). Thus, anchropogenica lly induced NOx emissions contribute to enhanced greenhouse effect and to stratospheric ozone depletion in the time scale of more than a cen tury.