From March to May 2023, ESR Sonja visited Natalia and Lars-Eric at the MIO in Marseille for the analysis of the Southern Ocean mercury samples that she collected together with ESRs David and Jared during the SCALE winter cruise in July 2022. The data analysis is still ongoing.

Sample boxes from the Southern Ocean
A picture from Marseille (close to MIO)

Fieldwork: Arctic Ocean II cruise

In August 2024, ESR Sonja participated in the Arctic Ocean II cruise with the Norwegian Polar Institute onboard the research vessel Kronprins Haakon. The cruise track consisted of two transects across the slope from the shelf into the deep Nansen basin North of Svalbard. During the three weeks on board, Sonja collected a variety of samples for mercury speciation and distribution. The samples collected include CTD samples from the water column (picture 2) for total mercury, methylmercury and monomethylmercury analysis. Moreover, zooplankton samples were collected using an MIK-net and sorted by species at each of the stations (picture 3). Close to the stations, fish muscle tissue samples were collected from pelagic trawling and at one station benthic biota samples were collected. At four stations, surface sediment samples were collected from a box corer (picture 4). At the Northernmost station (84N), Sonja collected sea ice samples from three 140 cm long ice cores that were sectioned into 20 cm sections (Pictures 5-7). Currently, these samples are analyzed at Stockholm University.

Sonja sampling sea water from the CTD. Photo credit: Jessica Cook, Arctic Council Secretariat
Sonja sorting zooplankton in the wet lab. Photo credit: Jessica Cook, Arctic Council Secretariat
Sonja, Nalan and Flore with the box corer


Ice station with the RV Kronprins Haakon in the background. Photo credit: Jessica Cook, Arctic Council Secretariat
Collection of an ice core
Sonja and a 20 cm ice section for mercury samples
The scientific crew of the Polar Ocean II cruise. Photo credit: Jessica Cook, Arctic Council Secretariat