A research cruise was conducted onboard the research vessel Kronprins Haakon from April 17th to April 24th 2023. The main objective was to recover a K-lander deployed on 14 April 2022 and a mooring deployed on 7 March 2023 to observe the intense methane seep at the pingo south in Storfjordrena. The scientific objectives of the K-lander and the mooring are to estimate i) the seasonal and inter-annual variability of methane release from an intense methane release site south of Svalbard; ii) how high methane is transported; iii) the influence of oceanic setting in this potential variability.
The K-lander was designed in a collaboration between Kongsberg Maritime and CAGE (Centre of Excellence for Arctic Gas Hydrate, Environment and Climate) in 2015 and was deployed several times offshore Svalbard and in the Barents Sea. It is an infrastructure of 3.6m in diameter and 1.6m in height. Its centre is the most protected and robust, and therefore contains all instruments: an ADCP (Acoustic Doppler Current Profiler Workhorse Long Ranger 75 Khz) to measure the current in the water column as well as the backscatter signal, a methane and a CO2 CONTROS sensors, and a SeapHOx (Seabird) to measure temperature, salinity, oxygen and pH.
The mooring is 300m and includes an ADCP Workhorse 300 kHz from Teledyne looking upward, two Seabird CTDs and a CONTROS methane sensor connected by fishing grade floating polypropylene ropes, steel wires and chains and balanced by buoyancy (Vitrovex FS-6700-17 glass spheres from NAUTILUS MARINE SERVICE).
Author(s): Benedicte Ferré