Posters

Poster Session 3, Wednesday,  October  5, 16:00–18:00

Poster 103

A pilot study on DOM optical properties in surface waters of Kongsfjorden, Isfjorden and Hornsund (Svalbard) – DOMinEA project

The goal of the DOMinEA project is to characterize in detail the DOM optical properties in the West Spitsbergen Fjords. A pilot study on DOM optical properties in surface waters of Kongsfjorden, Isfjorden and Hornsund was conducted in the summer of 2018 – 2019. Water samples for determination of DOM absorption coefficient and DOM fluorescence were collected. The inherent optical properties were measured with the use of the Integrated Optical-Hydrological Probe. The initial results revealed significant differences in both quantitative and qualitative properties of DOM optical characteristics between the three investigated fjords. A five-component model has been developed based on 119 EEM spectra and the application of the PARAFAC. It indicated that the protein-like fluorophores dominate FDOM composition in investigated fjords. The contribution of fluorescence intensity of the identified protein-like components (Ip) to the total fluorescence intensity (It) varied from 59 % to 75 %, and it was the highest in Hornsund and the lowest in Kongsfjorden. The most distinct difference in FDOM composition was the dominance of fluorescence intensity of the tryptophan–like fluorophores. The high Ip in the surface waters in Hornsund may result from the glacier meltwater discharge or the autochthonous production. This statement is supported by measurements of vertical profiles of the agp(676). These findings suggest that several local scale and mesoscale processes could impact DOM composition in the study area, and that will be our focus in the later stages of the project.

Monika Zabłocka, Institute of Oceanology Polish Academy of Sciences, [email protected], 0000-0002-1803-7042

Piotr Kowalczuk, Institute of Oceanology Polish Academy of Sciences, [email protected]

Karolina Borzycka, Institute of Oceanology Polish Academy of Sciences, [email protected]

Marta Konik, Institute of Oceanology Polish Academy of Sciences, [email protected]

Katarzyna Dragańska-Deja, Institute of Oceanology Polish Academy of Sciences, [email protected]