Abstract:

339 gas samples above oceanic surface were collected on the cruise of "Xuelong" expeditionary ship and nitrous oxide concentrations were analyzed in the laboratory. Results showed that Atmospheric average N₂O concentration was 309±3.8 nL/L above the surface of northern Pacific and Arctic ocean. N₂O concentrations were significantly different on the northbound and southbound track in the range of the same latitude, 308.0±3.5 nL/L from Shanghai harbor to the Arctic and 311.9±2.5 nL/L from the Arctic to Shanghai harbor. N₂O concentration had a greater changing magnitude on the mid- and high-latitude oceanic surface of northern Pacific Ocean than in the other latitudinal ranges. The correlation between the concentrations of the compositions in the aerosol samples and atmospheric N₂O showed that continental sources had a great contribution on atmospheric N₂O concentration above the oceanic surface. Atmospheric N₂O concentration significantly increased when the expeditionary ship approached Shanghai harbor. The average N₂O concentrations were 315.1±2.5 nL/L, 307.2±1.4 nL/L and 306.2±0.7 nL/L, respectively, at Shanghai harbor, at ice stations and at floating ices. The distribution of N₂O concentrations was related with air pressure and temperature above the mid- and high-latitude Pacific Ocean.

Key words: Arctic Ocean, Northern Pacific Ocean, Nitrous oxide, Atmosphere