Abstract
Carbon monoxide (CO) influences the radiative budget and oxidative
capacity of the atmosphere over the Arctic Ocean, which is a source of
atmospheric CO. Yet, oceanic CO cycling is understudied in this area,
particularly in view of the ongoing rapid environmental changes.
Therefore, incubation experiments were conducted in the Fram Strait in
August/September 2019 under light, dark and pH-manipulated conditions.
Lower pH did not affect CO cycling. Enhanced CO production and
consumption correlated with high absorption of colored dissolved organic
material and low dissolved nitrate concentrations, suggesting microbial
CO uptake under oligotrophic conditions which, in turn, controls the CO
surface concentrations. Both production and consumption of CO will
likely increase in the future, but it is unknown which process will
dominate. Our results will help to improve models predicting future CO
concentrations and emissions and their effects on the radiative budget
and the oxidative capacity of the Arctic atmosphere.