Mare Incognitum is maintained by researchers at the Institute for Arctic and Marine Biology at UiT The Arctic University of Norway. Mare Incognitum provides a platform to showcase ongoing and recently finished projects dealing with different aspects of Arctic marine ecology lead by researchers at UiT, colleagues within the ARCTOS network as well as international partners. Mare Incognitum also showcases infrastructure such as the Kongsfjorden and Rijpfjorden Observatory Program (KROP) and the ArcLight observatory in Ny-Ålesund.
Using acoustic records, Hobbs et al. show that zooplankton in an Arctic fjord position themselves vertically in relation to light. A depth-varying line of constant light intensity (isolume) bascially forms a ceiling above which zooplankton won’t venture.The value of this isolume is set at the lower limit of photobehaviour reponses of Calanus spp. and krill. These results suggest that zooplankton follow a foraging strategy that will keep visual predation risk roughly constant under changing light conditions. Thus they already have a strategy to cope with climate induced changes in the under water light climate, such as those caused by the reduction of sea ice.
We were lucky enough to get ship time with UiT’s research vessel Helmer Hanssen this autumn, despite all the social distancing restrictions. With a scientific crew consisting of only 13 people we went from Tromsø to Svalbard to service the ocean observatories (KROP) in Kongsfjorden and Rijpfjorden, maintain the photographic benthos time series in Kongsfjorden, Smeerenburg and Isfjorden, and to conduct some experimental work for CalAct. Everyone was happy to get out of the (home) office, the sea was mainly calm, and best of all: the Rijpfjorden mooring was still there! Ice conditions in 2019 made it impossible to get into Rijpfjorden last year, and the lost of the Kongsfjorden mooring due to corossion last year had made us a bit anxious, but the retrival was successfull and 2 years of data have been recorded!
In July 2019, a set of ArcticABC ice tethered observatories (ITOs) got deployed from R/V Kronprins Haakon at about 84°N. The ITOs consisted of an Acoustic Zooplankton Fish Profiler (AZFP), a Sea-Ice Mass Balance Array (SIMBA), an automated weather station (AWS) and the newly designed high-sensitivity Light & Temperature chain (LT-ITO). During the drift, the SIMBA, AWS and LT-ITO were unfortunately lost at some point. Their data is safe though, as it was transmitted by Iridium. The AZFP data was successfully downloaded by a data harvesting plane with the help of a broadband radio, only a short time before the AZFP-ITO was washed ashore on the northern coast of Iceland. The surface buoy has been recovered by Icelandic SAR, but the AZFP is unfortunately lost. We have the position of an object in the water closed to where the unit beached itself, which we will check out once the Corona restrictions are eased.
Mare Incognitum is an umbrella platform to showcase ongoing projects of researchers at UiT The Arctic University of Norway with other institutes and universities in northern Norway and across the globe. Mare incognitum provides a platform to post news, links, publications and to present team members. The site is maintain by the research group of Prof. Jørgen Berge at UiT, Tromsø, Norway.