Fundamental marine ecosystem change during rapid climate change events

Jan 24, 2014
Fundamental marine ecosystem change during rapid climate change events
Diatoms. Credit: Rovag [CC-BY-3.0]

(Phys.org) —Marine ecosystems – especially in nutrient-starved areas of the ocean – are very sensitive to abrupt climate change, according to new research from the University of Bristol.

The research, which involved scientists from the University of Bristol'sEarth Science department, Cardiff University, Woods Hole Oceanographic Institute and Columbia University, is published today in Nature Communications. The scientists have used evidence from deep-sea fossils to show that there were fundamental changes in the marine ecosystem during rapid climate change events, which ultimately changed how was buried in the .

The team studied algae known as diatoms, and some kinds of protists and sponges, which make their skeletons out of biogenic opal, a glass-like material made out of silicon. Using the chemistry of biogenic opal, the authors show that the physical and chemical structure of the North Atlantic Ocean was very different during Heinrich Stadial One, a rapid climate event approximately 16,000-19,000 years ago. During this event, the concentration of silicon in the ocean changed significantly and allowed for the growth of large diatoms. The expansion of large diatoms allowed more carbon to sink into the abyss and become locked into the sedimentary record.

Dr. Kate Hendry, a Royal Society Research Fellow and member of the Cabot Institute at the University of Bristol, said: "We know from climate records that there were abrupt changes in climate as the Earth warmed up after the last ice age between fifteen and twenty thousand years ago. These changes in climate had massive influence on the oceans, rapidly changing the physical circulation and essential nutrient supplies, which significantly impacted marine life.

"The implications of this work are that - especially in nutrient-starved areas of the oceans such as the North Atlantic gyre - are very sensitive to shifts in ocean circulation that are brought about by climate change, and that these ecological changes can have a big impact in carbon burial."

Although evidence exists for increased diatom burial in the North Atlantic during deglaciation, this study provides the first quantitative evidence for changes in silica cycling during this millennial-scale event. This new study also shows that changes in ocean chemistry and restructuring of the marine ecosystem helped to remove carbon from the ocean during a period where global atmospheric carbon dioxide was gradually increasing.

This research was funded by a number of research bodies, including the National Environment Research Council (NERC) and the Royal Society.

Further information: Paper "Silicon isotopes indicate enhanced carbon export efficiency in the North Atlantic during deglaciation" by Katharine Hendry, Laura Robinson, Jerry McManus and James Hays, is available in Nature Communications.

Explore further: Study examines iceberg shifts in North Atlantic

More information: "Silicon isotopes indicate enhanced carbon export efficiency in the North Atlantic during deglaciation." Katharine R. Hendry, Laura F. Robinson, Jerry F. McManus, James D. Hays. Nature Communications 5, Article number: 3107 DOI: 10.1038/ncomms4107. Received 18 June 2013 Accepted 13 December 2013 Published 23 January 2014

Related Stories

Study examines iceberg shifts in North Atlantic

Jan 16, 2014

(Phys.org) —Some Heinrich events – periodic massive iceberg surges into the North Atlantic that were previously thought to have weakened the global ocean conveyor belt circulation and sent Earth's climate ...

The fate of bioavailable iron in Antarctic coastal seas

Dec 13, 2013

Science is exploring many options for carbon dioxide sequestration in order to mitigate the climatological impact of CO2. One of these is geoengineering: deliberate, large-scale intervention in the Earth's ...

Recommended for you

Asian monsoon much older than previously thought

17 hours ago

The Asian monsoon already existed 40 million years ago during a period of high atmospheric carbon dioxide and warmer temperatures, reports an international research team led by a University of Arizona geoscientist.

Rules of thumb for climate change turned upside down

17 hours ago

With a new analysis of land regions, ETH climate researcher are challenging the general climate change paradigm that dry regions are getting drier and wet regions are getting wetter. In some regions they ...

Tropical Storm Odile taken on by two NASA satellites

Sep 12, 2014

As Tropical Storm Odile continues to affect Mexico's west coast and stir up dangerous surf, NASA's TRMM and Aqua satellites provided forecasters information on clouds and rainfall in the coast-hugging storm. ...

User comments : 0