THE AEGEAN SEA AS A SOURCE OF ATMOSPHERIC NITROUS-OXIDE AND METHANE

During the EGAMES (Evasion of GAses from the MEditerranean Sea) expedi tion in July 1993 we determined the concentrations of nitrous oxide an d methane in the atmosphere and in the surface waters of the Aegean Se a, the northwestern Levantine Basin, the eastern Ionian Sea and the Am vrakikos Bay. Both gases were found to be supersaturated in all sample d areas. Nitrous oxide was homogeneously distributed with a mean satur ation of 105 +/- 2%, showing no differences between shelf and open oce an areas, whereas methane saturation values ranged from about 1.2 time s (northwestern Levantine Basin) to more than 5 times solubility equil ibrium (Amvrakikos Bay estuary). Therefore the Aegean Sea and the adja cent areas were sources of atmospheric nitrous oxide and methane durin g the study period.