Quaternary contourite drifts of the Western Spitsbergen margin

The study of contourite drifts is an increasingly used tool for understanding the climate history of the oceans. In this paper we analyse two contourite drifts along the continental margin west of Spitsbergen, just south of the Fram Strait where significant water mass exchanges impact the Arctic climate. We detail the internal geometry and the morphologic characteristics of the two drifts on the base of multichannel seismic reflection data, sub-bottom profiles and bathymetry. These mounded features, that we propose to name Isfjorden and Bellsund drifts, are located on the continental slope between 1200 and 1800 m depth, whereas the upper slope is characterized by reduced- or non-deposition. The more distinct Isfjorden Drift is about 25 km wide and 45 km long, and over 200 ms TWT thick. We revise the 13 years-long time series of velocity, temperature, and salinity obtained from a mooring array across the Fram Strait. Two distinct current cores are visible in the long-term average. The shallower current core has an average northward velocity of about 20 cm/s, while the deeper bottom current core at about 1450 m depth has an average northward velocity of about 9 cm/s. We consider Norwegian Sea Deep Water episodically ventilated by relatively dense and turbid shelf water from the Barents Sea responsible for the accumulation of the contourites. The onset of the drift growth west of Spitsbergen is inferred to be about 1.3 Ma and related to the Early Pleistocene glacial expansion recorded in the area. The lack of mounded contouritic deposits on the continental slope of the Storfjorden is related to consecutive erosion by glacigenic debris flows. The Isfjorden and Bellsund drifts are inferred to contain the record of the regional palaeoceanography and glacial history and may constitute an excellent target of future scientific drilling

The Shell Ocean Discovery XPRIZE Competition Impact on the Development of Ocean Mapping Possibilities

The paper presents the impact that the XPRIZE Foundation competition, the Shell Ocean Discovery XPRIZE, has had on the development of current ocean mapping possibilities. A race for the prize has accelerated the development of innovative seabed mapping approaches that concentrated on new systems engineering or cutting-edge and innovative methods of existing equipment exploitation. The GEBCO - Nippon Foundation (NF) Alumni Team’s entry is presented in details as a state of the art example of mature and robust ocean-mapping solution utilizing a high degree of autonomy and providing the possibilities of deep-ocean mapping that were unattainable before.W artykule przedstawiono wpływ konkursu Shell Ocean Discovery XPRIZE na rozwój współczesnych technik mapowania głębokowodnych obszarów oceanicznych. Wyścig po główną nagrodę stał się motywacją do pracy nad innowacyjnymi metodami eksploracji głębin i nowatorskim wykorzystaniem istniejących systemów. Przykładem jest przedstawiony szczegółowo system zaproponowany przez drużynę GEBCO - Nippon Foundation (NF) Alumni. Połączenie sprawdzonego pojazdu podwodnego (Hugin) z nową, zaprojektowaną w ramach udziału w konkursie jednostką nawodną (SEA-KIT) tworzy nieistniejące wcześniej możliwości pozyskiwania danych o ukształtowaniu dna akwenów głębokowodnych

The International Bathymetric Chart of the Arctic Ocean (IBCAO) Version 4.0

Bathymetry (seafloor depth), is a critical parameter providing the geospatial context for a multitude of marine scientific studies. Since 1997, the International Bathymetric Chart of the Arctic Ocean (IBCAO) has been the authoritative source of bathymetry for the Arctic Ocean. IBCAO has merged its efforts with the Nippon Foundation-GEBCO-Seabed 2030 Project, with the goal of mapping all of the oceans by 2030. Here we present the latest version (IBCAO Ver. 4.0), with more than twice the resolution (200 × 200 m versus 500 × 500 m) and with individual depth soundings constraining three times more area of the Arctic Ocean (∼19.8% versus 6.7%), than the previous IBCAO Ver. 3.0 released in 2012. Modern multibeam bathymetry comprises ∼14.3% in Ver. 4.0 compared to ∼5.4% in Ver. 3.0. Thus, the new IBCAO Ver. 4.0 has substantially more seafloor morphological information that offers new insights into a range of submarine features and processes; for example, the improved portrayal of Greenland fjords better serves predictive modelling of the fate of the Greenland Ice Sheet