Navigation Links
Study of oceans' past raises worries about their future
Date:6/14/2013

The ocean the Titanic sailed through just over 100 years ago was very different from the one we swim in today. Global warming is increasing ocean temperatures and harming marine food webs. Nitrogen run-off from fertilizers is causing coastal dead zones. A McGill-led international research team has now completed the first global study of changes that occurred in a crucial component of ocean chemistry, the nitrogen cycle, at the end of the last ice age. The results of their study confirm that oceans are good at balancing the nitrogen cycle on a global scale. But the data also shows that it is a slow process that may take many centuries, or even millennia, raising worries about the effects of the scale and speed of current changes in the ocean.

"For the first time we can quantify how oceans responded to slow, natural climate warming as the world emerged from the last ice age," says Prof. Eric Galbraith from McGill University's Department of Earth and Oceanic Sciences, who led the study. "And what is clear is that there is a strong climate sensitivity in the ocean nitrogen cycle."

The nitrogen cycle is a key component of the global ocean metabolism. Like the proteins that are essential to human health, nitrogen is crucial to the health of oceans. And just as proteins are carried by the blood and circulate through the body, the nitrogen in the ocean is kept in balance by marine bacteria through a complicated cycle that keeps the ocean healthy. The phytoplankton (microscopic organisms at the base of the food chain) 'fix' nitrogen in the shallow, sunlit waters of the ocean, and then as they die and sink, nitrogen is eliminated (a process known as 'denitrification') in dark, oxygen-poor pockets of the ocean depths.

Using sediment gathered from the ocean floor in different areas of the world, the researchers were able to confirm that as the ice sheets started melting and the climate warmed up at the end of the last ice age, 18,000 years ago, the marine nitrogen cycle started to accelerate. The ocean had stabilized itself in its new, warmer state, in which the overall nitrogen cycle was running faster, by about 8,000 years ago. Given the current dramatic rate of change in the ocean nitrogen cycle the researchers are not sure how long it will take for marine ecosystems to adapt.

"We are changing the planet in ways we are not even aware of," says Galbraith. "You wouldn't think that putting carbon dioxide into the atmosphere would change the amount of nitrogen available to fish in the ocean, but it clearly does. It is important to realize just how interconnected everything is."


'/>"/>

Contact: katherine gombay
katherine.gombay@mcgill.ca
514-398-2189
McGill University
Source:Eurekalert

Related biology news :

1. Study helps managers identify regions with multiple threat potential, including wildfires
2. Dads life stress exposure can affect offspring brain development, Penn Study finds
3. NIH awards UCI $10 million to study early-life origins of adolescent mental disorders
4. New Loyola study on hepatitis C virus entry factor
5. Biofuels will play integral role in Californias energy future, says new EBI study
6. New study proposes solution to long-running debate as to how stable the Earth system is
7. Study finds disincentives to energy efficiency can be fixed
8. Study finds taking probiotics has benefits for patients in hospitals
9. New study explains cognitive ability differences among the elderly
10. Oncologists are stressed and have difficulty discussing death with patients -- Ben-Gurion U. study
11. Stem cell study could aid quest to combat range of diseases
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/3/2016)... 2016 Das DOTM ... Nepal hat ein 44 Millionen ... Kennzeichen, einschließlich Personalisierung, Registrierung und IT-Infrastruktur, an ... und Implementierung von Identitätsmanagementlösungen. Zahlreiche renommierte internationale ... teilgenommen, aber Decatur wurde als konformste und ...
(Date:5/24/2016)... IRVINE, Calif. , May 24, 2016 Ampronix facilitates superior patient care ... LMD3251MT  3D medical LCD display is the latest premium product recently added to ... ... ... Sony 3d Imaging- LCD Medical Display- Ampronix News ...
(Date:5/3/2016)... , May 3, 2016  Neurotechnology, a provider ... MegaMatcher Automated Biometric Identification System (ABIS) , ... multi-biometric projects. MegaMatcher ABIS can process multiple complex ... any combination of fingerprint, face or iris biometrics. ... SDK and MegaMatcher Accelerator , which ...
Breaking Biology News(10 mins):
(Date:6/27/2016)... , June 27, 2016   Ginkgo Bioworks , ... industrial engineering, was today awarded as one of ... of the world,s most innovative companies. Ginkgo Bioworks ... for the real world in the nutrition, health ... work directly with customers including Fortune 500 companies ...
(Date:6/23/2016)... (PRWEB) , ... June 23, 2016 , ... ... the release of its second eBook, “Clinical Trials Patient Recruitment and Retention Tips.” ... and retention in this eBook by providing practical tips, tools, and strategies for ...
(Date:6/23/2016)... , June 23, 2016 Houston Methodist ... the Cy-Fair Sports Association to serve as their ... agreement, Houston Methodist Willowbrook will provide sponsorship support, ... connectivity with association coaches, volunteers, athletes and families. ... the Cy-Fair Sports Association and to bring Houston ...
(Date:6/23/2016)... ... June 23, 2016 , ... Supplyframe, ... of the Supplyframe Design Lab . Located in Pasadena, Calif., the Design ... of how hardware projects are designed, built and brought to market. , The ...
Breaking Biology Technology: