Reduction of atmospheric N deposition to the Yellow Sea of Northeastern Pacific Ocean for COVID-19 period

Abstract

Rapid population growth and industrialization in Northeast Asian countries have caused the excessive input of atmospheric N to the Yellow Sea of the Northeastern Pacific Ocean. Since the Yellow Sea is located between Northern China and Korean Peninsula, the abundant atmospheric N has been deposited to the Yellow Sea with 71% of total new N input, implying an increase in marine primary productivity. We monitored atmospheric N deposition and analyzed isotopic values of [NO3–] and total carbon, nitrogen, and sulfur concentrations for COVID 19. During COVID-19, The depositions of [NO3–] and [NH4+] decreases by 38% and 68.7% for summer and 49.5% and 49.6% for winter, respectively. The isotopic values of [NO3–] for COVID-19 indicated that the fossil fuel combustion and vehicles were main sources for atmospheric N depositions for winter and summer, respectively. The isotopic information was not different from those of pre-COVID-19, implying the reduction of N deposition and no change of N pol