Their results, which are published this month in the Journal of Geophysical Research, show that there is a mismatch between what goes into the Arctic Ocean and what comes out.
This is the first study to look at the transport of dissolved inorganic nutrients nitrate, phosphate and silicate together, all of which are essential for life in the ocean. The study combined measurements of nutrient concentrations with measurements of how much water was transported across the main Arctic gateways – Davis Strait, Fram Strait, the Barents Sea Opening and Bering Strait – in summer 2005.
Growth of the tiny plants at the base of marine food chains, microalgae, in the Arctic Ocean is fuelled by nutrient inputs from the Pacific and Atlantic Oceans, and from rivers around the Arctic Ocean rim. These riverine inputs are increasing as a result of increasing temperatures, because nutrients previously locked up in frozen soils – or 'permafrost' – are being released as the permafrost thaws.
While scientists are trying to understand how this increase in nutrients is influencing the growth of Arctic microalgae, the final fate of the nutrients is also of interest because they may support marine ecosystems elsewhere, carried there by ocean currents.
In the study, the researchers looked at all oceanic inputs and outputs of the three nutrients. They found that the nitrate coming into the Arctic Ocean balanced how much goes out. But for silicate and phosphate, more goes out into the North Atlantic than comes into the Arctic Ocean.
"These findings have important implications," says Dr Sinhué Torres-Valdés of the National Oceanography Centre, lead author of the paper.
"Firstly, the imbalances indicate that the Arctic Ocean is an important source of phosphate and silicate to the North Atlantic. Secondly, while nitrate transports are balanced, in the Arctic large amounts of nitrogen are lost to the atmosphere as nitrogen gas through a process called denitrification."
So where do the extra nutrients come from?
"Data suggest that rivers can provide most of the silicate that is transported to the North Atlantic, which implies that further alterations on Arctic river nutrient loads will have a direct impact on nutrient transports to the Atlantic.
"In the case of nitrate and phosphate, no obvious sources seem to provide enough to offset the imbalance. We are therefore investigating the possibility that the extra nitrate and phosphate comes from dissolved organic matter – the decaying remains of microorganisms in the ocean and decaying remains from soils in river loads.
"We suggest that this work can serve as a baseline for monitoring how nutrient availability varies as the Arctic continues to respond to the changing climate," says Dr Torres-Valdés.
The study, funded by the Natural Environment Research Council as part of the International Polar Year project 'Arctic Synoptic Basin-wide Oceanography', was a collaboration between the National Oceanography Centre, University of Southampton Ocean and Earth Science, Institute of Ocean Sciences Canada, Bedford Institute of Oceanography, Alfred Wegener Institute for Polar and Marine Research, and University of Alaska Fairbanks.
The paper 'Export of nutrients from the Arctic Ocean' was featured in Research Spotlight of EOS Transactions, American Geophysical Union.
Notes for editors
1. Reference: Torres-Valdés, S., T. Tsubouchi, S. Bacon, A. C. Naveira-Garabato, R. Sanders, F. A. McLaughlin, B. Petrie, G. Kattner, K. Azetsu-Scott, and T. E. Whitledge (2013), Export of nutrients from the Arctic Ocean, J. Geophys. Res.: Oceans, 118, doi:10.1002/jgrc.20063
2. Research Spotlight, EOS Transactions, American Geophysical Union highlights exciting new research from AGU journals. The paper was featured in Volume 94, Number 13, 26 March 2013.
3. The photo was taken during one of the expeditions to the Arctic aboard the Russian icebreaker Kapitan Dranitsyn in 2008 as part of the International Polar Year NERC-funded project Arctic Synoptic Basin-wide Oceanography (ASBO). The image shows the back of the icebreaker, which was carving out a circular opening in the ice at a sampling station. Credit Sinhué Torres-Valdés.
4. The National Oceanography Centre (NOC) is the UK's leading institution for integrated coastal and deep ocean research. NOC operates the Royal Research Ships James Cook and Discovery and develops technology for coastal and deep ocean research. Working with its partners NOC provides long-term marine science capability including: sustained ocean observing, mapping and surveying, data management and scientific advice.
5. NOC operates at two sites, Southampton and Liverpool, with the headquarters based in Southampton.
6. Among the resources that NOC provides on behalf of the UK are the British Oceanographic Data Centre (BODC), the Marine Autonomous and Robotic Systems (MARS) facility, the National Tide and Sea Level Facility (NTSLF), the Permanent Service for Mean Sea Level (PSMSL) and British Ocean Sediment Core Research Facility (BOSCORF).
7. The National Oceanography Centre is wholly owned by the Natural Environment Research Council (NERC).
Catherine Beswick, National Oceanography Centre
Catherine Beswick | EurekAlert!
Further reports about: > American Geophysical Union > Arctic Ocean > Atlantic mollies > EOS > Environment > Environment Research > Facility Management > Marine science > Natural Environment Research > Oceanography > Pacific Ocean > Polar Day > Synoptic > deep ocean > food chain > marine ecosystem > sea snails
WAKE-UP provides new treatment option for stroke patients | International study led by UKE
17.05.2018 | Universitätsklinikum Hamburg-Eppendorf
First form of therapy for childhood dementia CLN2 developed
25.04.2018 | Universitätsklinikum Hamburg-Eppendorf
So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics
Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...
The historic first detection of gravitational waves from colliding black holes far outside our galaxy opened a new window to understanding the universe. A...
A team led by Austrian experimental physicist Rainer Blatt has succeeded in characterizing the quantum entanglement of two spatially separated atoms by observing their light emission. This fundamental demonstration could lead to the development of highly sensitive optical gradiometers for the precise measurement of the gravitational field or the earth's magnetic field.
The age of quantum technology has long been heralded. Decades of research into the quantum world have led to the development of methods that make it possible...
Cardiovascular tissue engineering aims to treat heart disease with prostheses that grow and regenerate. Now, researchers from the University of Zurich, the Technical University Eindhoven and the Charité Berlin have successfully implanted regenerative heart valves, designed with the aid of computer simulations, into sheep for the first time.
Producing living tissue or organs based on human cells is one of the main research fields in regenerative medicine. Tissue engineering, which involves growing...
A team of scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg investigated optically-induced superconductivity in the alkali-doped fulleride K3C60under high external pressures. This study allowed, on one hand, to uniquely assess the nature of the transient state as a superconducting phase. In addition, it unveiled the possibility to induce superconductivity in K3C60 at temperatures far above the -170 degrees Celsius hypothesized previously, and rather all the way to room temperature. The paper by Cantaluppi et al has been published in Nature Physics.
Unlike ordinary metals, superconductors have the unique capability of transporting electrical currents without any loss. Nowadays, their technological...
02.05.2018 | Event News
13.04.2018 | Event News
12.04.2018 | Event News
18.05.2018 | Power and Electrical Engineering
18.05.2018 | Information Technology
18.05.2018 | Information Technology