NITROUS-OXIDE EMISSIONS FROM THE ARABIAN SEA

Dissolved and atmospheric nitrous oxide (N2O) were measured on the leg s 3 and 5 of the RN Meteor cruise 32 in the Arabian Sea. A cruise trac k along 65 degrees E was followed during both the intermonsoon (May 19 95) and the southwest (SW) monsoon (July/August 1995) periods. During the second leg the coastal and open ocean upwelling regions off the Ar abian Peninsula were also investigated. Mean N2O saturations for the o ceanic regions of the Arabian Sea were in the range of 99-103 % during the intermonsoon and 103-230% during the SW monsoon. Computed annual emissions of 0.8-1.5 Tg N2O for the Arabian Sea are considerably highe r than previous estimates, indicating that the role of upwelling regio ns, such as the Arabian Sea, may be more important than previously ass umed in global budgets of oceanic N2O emissions.