Monitoring of chlorophyll concentrations in the Barents Sea: comparison of long-term in situ and satellite data

Abstract

Phytoplankton organisms are the basis of the trophic chain and primary producers in the pelagial of the Barents Sea. The variation in phytoplankton biomass during the growing season is closely related to the change in chlorophyll a concentration. The data on the concentration of chlorophyll a in situ collected during the long-term (2006, 2007, 2010, 2013, 2015–2019) MMBI expedition research were compared with remote satellite sensing data. More than 200 in situ samples and satellite data were analyzed on the same dates in a 5x5 km square centered on the sampling point. It was revealed that permanent cloud cover over the Barents Sea interferes with the complete remote monitoring of this water area. The small number of coincidences of concentrations in situ with satellite data does not allow achieve global monitoring goals. Having analyzed the relationship of sea surface temperature as a key factor affecting the spatial and temporal distribution of chlorophyll a, a high degree of correlation (r = 0.89) between the parameters under consideration was determined, which indicates a sufficiently high reproducibility of the data of field measurements by satellite instruments.