Mooring Service Cruise (MSC) 2022
Authors: Lundesgaard Øyvind , Sundfjord Arild , Sortland Julie 
Published: February 2023

The main objective of the cruise was to retrieve and deploy ocean moorings in the north-western Barents Sea and on the continental slope north of Kvitøya for the Nansen Legacy and A-TWAIN projects. A secondary objective was to perform hydrographic surveys in regions of Atlantic Water inflow and other regions of interest. In addition, the cruise aided other research groups by deployment and recovery of minor equipment at sites along the cruise trajectory.
In general, mooring operations were conducted during day hours, while nights were used to collect CTD data along various transects. Mooring work was completed quickly, efficiently, and ahead of schedule. This left ample time for additional pre-planned hydrographic surveys after the mooring work was complete.
The cruise departed from Longyearbyen in the afternoon on 02.10.2022. An IMR ARGO float was deployed north of Spitsbergen the day after. On the following day, the ship operated for three days in the area around the A-TWAIN mooring array on the continental slope north of Kvitøya. Here, four moorings were recovered, and four were deployed, and hydrographic transects (CTDs) were conducted across the Atlantic Water inflow current and across northern Kvitøya Trough.
After transiting south from the A-TWAIN area on the evening of 06.10.2022, another transect was conducted at night across the southern outlet of Kvitøya Trough. Mooring work began the following morning at the Nansen Legacy M1 location in the north-western Barents Sea. Two moorings were recovered and redeployed. Afterwards, a cross-slope transect was conducted intersecting the M1 mooring location. In the following days, consecutive transects were conducted into the through extending from M1 to Hartogbukta, along the Storisstraumen glacier front, from Storisstraumen southeast across the ocean basin, and along the bathymetric saddle west of Kong Karls Land.
During the transit back north and west, an additional brief transect was conducted outward from Wahlenbergfjorden into the Hinlopen Trough, to obtain data from a fjord with tidewater glaciers that are likely not influenced by Atlantic Water. On 10.10.2022 an NPI radio transmitter was retrieved from the island of Moffen by small boat. The ship then transited back to Longyearbyen, arriving in port on the evening of 11.10.2022.
Overall, the cruise was highly successful. All planned operations were completed in good time, allowing room for extensive hydrographic surveying as well as two minor deployment and recovery operations for other research groups. The success was in part due to fair weather during the first five days of the cruise and completely sea ice-free seas throughout. This allowed mooring work to take place in favourable conditions in an area where operations are often hampered by wind, swell, and sea ice. However, we would also like to highlight the competence and professionalism of the crew of the Kronprins Haakon as a key factor in the success of the cruise. Cooperation and communication with crewmembers on deck and on the bridge were excellent throughout. In addition, the cruise participants efficiently completed all the planned objectives despite the small size of the team (7 team members).