An international team of researchers analysed the available data taken from all previous studies of the Southern Ocean, together with satellite images taken of the area, to quantify the amount of iron supplied to the surface waters of the Southern Ocean.
They found that deep winter mixing, a seasonal process which carries colder and deeper, nutrient-rich water to the surface, plays the most important role in transporting iron to the surface. The iron is then able to stimulate phytoplankton growth which supports the ocean's carbon cycle and the aquatic food chain
They were also able to determine that following the winter iron surge, a recycling process is necessary to support biological activity during the spring and summer seasons.
Oceanographer, Dr Alessandro Tagliabue, from the University's School of Environmental Sciences, said: "We combined all available iron data, matched them with physical data from autonomous profiling floats and used the latest satellite estimates of biological iron demand to explore how iron is supplied to the phytoplankton in the Southern Ocean.
"This is important because iron limits biological productivity and air to sea CO2 exchange in this region. We found unique aspects to the iron cycle and how it is supplied by physical processes, making it distinct to other nutrients.
"This means that the Southern Ocean's nutrient supply would be affected by changes to the climate system (such as winds and freshwater input) differently to other areas of the ocean.
"We need to understand these unique aspects so that they can be used to better inform global climate predictions."
Dr Jean-Baptiste Sallée, from the Centre National de la Recherche Scientifique and the British Antarctic Survey, said: “We are really excited to make this discovery because until now we didn’t know the physical processes allowing iron to reach the ocean surface and maintain biological activity. The combination of strong winds and intense heat loss in winter strongly mixes the ocean surface and the mixing reaches deep iron reservoir.”
The Southern Ocean comprises the southernmost waters of the world oceans that encircle Antarctica. Researchers have long known the region is crucial in the uptake of atmospheric CO2 and that biological processes in the Southern Ocean influence the global ocean system via northward flowing currents.
The research involved the British Antarctic Survey, Southern Ocean Carbon and Climate Observatory, Sorbonne Universites, CNRS, University of Tasmania, University of Cape Town, University of Otago, University of Tasmania.
It is published in Nature Geoscience.
Sarah Stamper | EurekAlert!
Tundra study uncovers impact of climate warming in the Arctic
07.07.2015 | University of Edinburgh
NASA's infrared look at strengthening Typhoon Chan-Hom
07.07.2015 | NASA/Goddard Space Flight Center
When a duck paddles across a pond or a supersonic plane flies through the sky, it leaves a wake in its path. Wakes occur whenever something is traveling...
Researchers explore ultrafast control of magnetism across interfaces: A new study discovers how the sudden excitation of lattice vibrations in a crystal can trigger a change of the magnetic properties of an atomically-thin layer that lies on its surface.
A research team, led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter at CFEL in Hamburg, the University of Oxford, and the...
Wind turbines could be installed under some of the biggest bridges on the road network to produce electricity. So it is confirmed by calculations carried out by a European researchers team, that have taken a viaduct in the Canary Islands as a reference. This concept could be applied in heavily built-up territories or natural areas with new constructions limitations.
The Juncal Viaduct, in Gran Canaria, has served as a reference for Spanish and British researchers to verify that the wind blowing between the pillars on this...
New technique combines electron microscopy and synchrotron X-rays to track chemical reactions under real operating conditions
A new technique pioneered at the U.S. Department of Energy's Brookhaven National Laboratory reveals atomic-scale changes during catalytic reactions in real...
Think of an object made of iron: An I-beam, a car frame, a nail. Now imagine that half of the iron in that object owes its existence to bacteria living two and a half billion years ago.
Think of an object made of iron: An I-beam, a car frame, a nail. Now imagine that half of the iron in that object owes its existence to bacteria living two and...
25.06.2015 | Event News
16.06.2015 | Event News
11.06.2015 | Event News
07.07.2015 | Physics and Astronomy
07.07.2015 | Earth Sciences
07.07.2015 | Physics and Astronomy