Forty years after the discovery of hydrothermal vents, research into these unique habitats and their ecosystems is still in the exploratory phase. These recent discoveries have changed the way we understand life on Earth, have challenged knowledge of the origin of life and are now fueling exploration for extra-terrestrial life in our solar system. The remote Arctic Gakkel Ridge, though briefly investigated in regions by previous exploratory cruises, remains largely unexplored and ecosystems in this northerly, under-ice region, largely unknown. Despite evidence of venting at the ultra-slow spreading Gakkel Ridge being available since 2001 (Edmonds et al., 2003), visual confirmation of the Aurora vent field was not obtained until 2014, with a handful of images collected by a towed camera (Boetius et al., 2015). HACON proposes to return to the Gakkel Ridge with the new Norwegian icebreaker Kronprins Haakon, deep-diving ROV Ægir, the newly developed hybrid AUV Nereus Under Ice (NUI) from Woods Hole Oceanographic Institution (USA) and the towed Ocean Floor Observation and Bathymetry System (OFOBS) from AWI (Germany), to conduct the first full-scale multidisciplinary study of hydrothermal vents under permanent ice cover.
HACON will push the frontiers of deeps-sea and Arctic research, unraveling the physical, geochemical and ecological processes that shape the Aurora faunal communities and test the hypothesis that the Gakkel Ridge provides a connecting pathway for gene flow between the Pacific and Atlantic oceans. HACON will provide the first comprehensive study of deep (4000 m) hydrothermal vent ecosystems under ice in the Arctic region. HACON targets a key missing piece of the global vent biogeographic puzzle in a region that remains mostly unexplored because of its remote and climatologically challenging location. The project will provide empirical robust data of a pristine system prior to expected climate-change variations and increased human activities in the Arctic.
HACON will be developed under an ecosystem approach that integrates research in geology, geochemistry, physical oceanography, microbiology, micropaleontolgy, ecology, molecular biology and modelling. HACON will answer 3 main questions addressed in 4 integrated work packages: 1) What are the geologic controls on the vent-site formation on northerly ultra-slow spreading ridges and how do chemical signatures above these vents evolve within the water column (WP1)? 2) Which microbial and faunal communities are supported by such geochemical settings (WP2) and how do these function (WP3)? 3) What are the pathways and barriers to population connectivity between the deep Pacific, Arctic and Atlantic oceans (WP4)?
The hypothesis to be tested is that the Gakkel Ridge is a stepping stone for connectivity of vent fauna between the Pacific vents and Arctic Mid-Ocean Ridge. The alternative hypothesis is that the Gakkel Ridge communities have evolved in isolation and represent a new province in the global puzzle of vent biogeography.
TITLE: Hot vents in an ice-covered ocean: the role of the Arctic as a connectivity pathway between ocean basins – HACON.
TIMING: Nov. 2018 – Oct. 2021.
NATIONAL PARTNERS: NIVA (coordinator), UiT, UiB, HI.
INTERNATIONAL PARTNERS: AWI (Germany), WHOI (USA), UAVR (Portugal).