Photoproduction of nitric oxide in seawater

Ye Tian, Gui-Peng Yang, Chun-Ying Liu, Pei-Feng Li, Hong-Tao Chen, Hermann W. Bange
2019 Ocean Science Discussions  
<p><strong>Abstract.</strong> Nitric oxide (NO) is a short–lived intermediate of the oceanic nitrogen cycle. However, our knowledge about its production and consumption pathways in oceanic environments is rudimentary. In order to decipher the major factors affecting NO photochemical production, we irradiated artificial seawater samples as well as natural surface seawater samples in laboratory experiments. The seawater samples were collected during a cruise to the western tropical North Pacific
more » ... ical North Pacific Ocean (WTNP) from November 2015 to January 2016. NO photoproduction rates from dissolved nitrite in artificial seawater showed increasing trends with decreasing pH, increasing temperatures and increasing salinity. In contrast, NO photoproduction in from the natural seawater samples from the WTNP did not show any correlations with pH, water temperature and salinity as well as dissolved nitrite concentrations. NO photoproduction rates in the WTNP were significantly larger than the NO air–sea flux densities indicating a further NO loss process in the surface layer.</p>
doi:10.5194/os-2019-57 fatcat:6b3v55qearfchmyyrxw5gwmbmy