Nitrous oxide emissions from the Arabian Sea: A synthesis H. W. Bange1,7, M. O. Andreae1, S. Lal2, C. S. Law3, S. W. A. Naqvi4, P. K. Patra2,8, T. Rixen5,9, and R. C. Upstill-Goddard6 1Max Planck Institute for Chemistry, Mainz, Germany 2Physical Research Laboratory, Ahmedabad, India 3Plymouth Marine Laboratory, Plymouth, United Kingdom 4National Institute of Oceanography, Dona Paula, Goa, India 5University of Hamburg, Hamburg, Germany 6University of Newcastle, Newcastle upon Tyne, United Kingdom 7now at Institute for Marine Research, Kiel, Germany 8now at Frontier Research System for Global Change, Yokohama, Japan 9now at Center for Tropical Marine Ecology, Bremen, Germany
Abstract. We computed high-resolution
(1º latitude x 1º longitude) seasonal and annual nitrous oxide (N2O) concentration fields for the
Arabian Sea surface layer using a database containing more than 2400 values
measured between December 1977 and July 1997. N2O concentrations are
highest during the southwest (SW) monsoon along the southern Indian continental shelf. Annual emissions range from 0.33 to
0.70 Tg N2O and are dominated by fluxes from coastal regions during the SW and northeast
monsoons. Our revised estimate for the annual N2O flux from the Arabian
Sea is much more tightly constrained than the previous consensus derived using averaged in-situ data from a smaller number of studies. However, the
tendency to focus on measurements in locally restricted features in combination with insufficient seasonal data
coverage leads to considerable
uncertainties of the concentration fields and thus in the flux estimates, especially in the coastal zones of the northern and eastern Arabian Sea. The
overall mean relative error of the annual N2O emissions from the Arabian
Sea was estimated to be at least 65%.
Citation: Bange, H. W., Andreae, M. O., Lal, S., Law, C. S., Naqvi, S. W. A., Patra, P. K., Rixen, T., and Upstill-Goddard, R. C.: Nitrous oxide emissions from the Arabian Sea: A synthesis, Atmos. Chem. Phys., 1, 61-71, doi:10.5194/acp-1-61-2001, 2001.