Navigation Links
Greenhouse ocean study offers warning for future
Date:5/17/2011

The mass extinction of marine life in our oceans during prehistoric times is a warning that the Earth will see such an extinction again because of high levels of greenhouse gases, according to new research by geologists.

Professor Martin Kennedy from the University of Adelaide (School of Earth & Environmental Sciences) and Professor Thomas Wagner from Newcastle University (Civil Engineering and Geosciences) have been studying 'greenhouse oceans' oceans that have been depleted of oxygen and suffered from increases in carbon dioxide and temperature.

Using core samples drilled from the ocean bed off the coast of western Africa, the researchers studied layers of sediment from the Late Cretaceous Period (85 million years ago) across a 400,000-year timespan. They found a significant amount of organic material marine life buried within deoxygenated layers of the sediment.

"Our research points to a mass mortality in the oceans at a time when the Earth was going through a greenhouse effect, with high levels of carbon dioxide in the atmosphere, and rising temperatures, leading to a severe lack of oxygen (hypoxia) in the water that marine animals are dependent on," Professor Kennedy says.

"What's alarming to us as scientists is that there were only very slight natural changes that resulted in the onset of hypoxia in the deep ocean. This occurred relatively rapidly in periods of hundreds of years, or possibly even less not gradually over longer, geological time scales, which suggests that the Earth's oceans are in a much more delicate balance during greenhouse conditions than originally thought, and may respond in a more abrupt fashion to even subtle changes in temperature and CO2 levels than previously thought."

Professor Wagner says the results of their research, published in the Proceedings of the National Academy of Sciences (PNAS), have relevance for our modern world: "We know that 'dead zones' are rapidly growing in size and number in seas and oceans across the globe. These are areas of water that are lacking in oxygen and are suffering from increases of CO2, rising temperatures, nutrient run-off from agriculture and other factors."

Professor Kennedy says: "If you consider that the amount of carbon dioxide in our atmosphere has doubled over the past 50 years, this is like hitting our ecosystem with a sledge-hammer compared to the very small changes in incoming solar energy (radiation) which was capable of triggering these events in the past. This could have a catastrophic, profound impact on the sustainability of life in our oceans, which in turn is likely to impact on the sustainability of life for many land-based species, including humankind."

Professor Kennedy says the geological record offers a glimmer of hope thanks to a naturally occurring response to greenhouse conditions.

"After a hypoxic phase, oxygen concentration in the ocean seems to improve, and marine life returns. Our results show that natural processes of carbon burial kick in. Importantly, this rescue comes from the land, with soil-formed minerals acting to collect and bury excess dissolved organic matter in seawater. Burial of that excess carbon ultimately contributes to CO2 removal from the atmosphere, cooling the planet and the ocean.

"This is nature's solution to the greenhouse effect and it could offer a possible solution for us. If we are able to learn more about this effect and its feedbacks, we may be able to manage it, and reduce the present rate of warming threatening our oceans."


'/>"/>

Contact: Martin Kennedy
martin.kennedy@adelaide.edu.au
61-883-035-378
University of Adelaide
Source:Eurekalert

Related biology news :

1. Carbon dioxide scrubber captures greenhouse gases
2. Greenhouse gas auction revenues can help cut Md. electric use significantly, says study
3. Potent greenhouse gas more prevalent in atmosphere than previously assumed
4. MIT analysis shows how cap-and-trade plans can cut greenhouse emissions
5. MIT: Safe storage of greenhouse-gas carbon dioxide
6. Oil spray reduces greenhouse gas emissions from pig finishing barns
7. Termite insecticide a potent greenhouse gas
8. Detecting disease in greenhouse plants
9. Termite killer lingers as a potent greenhouse gas
10. New greenhouse gas identified
11. Fish oils reduce greenhouse gas emissions from flatulent cows
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/15/2016)... , June 15, 2016 ... market report titled "Gesture Recognition Market by Application Market - Global ... 2016 - 2024". According to the report, the  global ... billion in 2015 and is estimated to grow ... 48.56 billion by 2024.  Increasing application ...
(Date:6/2/2016)... The Department of Transport Management (DOTM) ... million US Dollar project, for the , Supply ... Enrolment, and IT Infrastructure , to ... implementation of Identity Management Solutions. Numerous renowned international vendors participated ... was selected for the most compliant and innovative ...
(Date:5/20/2016)... -- VoiceIt is excited to announce its new marketing ... working together, VoiceIt and VoicePass will offer an ... slightly different approaches to voice biometrics, collaboration between ... Both companies ... "This marketing and technology partnership allows VoiceIt ...
Breaking Biology News(10 mins):
(Date:6/23/2016)... 2016   EpiBiome , a precision microbiome engineering ... debt financing from Silicon Valley Bank (SVB). The financing ... advance its drug development efforts, as well as purchase ... "SVB has been an incredible strategic partner to us ... bank would provide," said Dr. Aeron Tynes Hammack ...
(Date:6/23/2016)... Ky. , June 23, 2016 ... two Phase 1 clinical trials of its complement ... placebo-controlled, single and multiple ascending dose studies designed ... pharmacodynamics (PD) of subcutaneous injection in healthy adult ... subcutaneously (SC) either as a single dose (ranging ...
(Date:6/23/2016)... San Francisco, CA (PRWEB) , ... June 23, ... ... capture (EDC) software, is exhibiting at the Pennsylvania Convention Center and will showcase ... DIA Annual conference. ClinCapture will also be presenting a scientific poster on Disrupting ...
(Date:6/23/2016)... June 23, 2016 ReportsnReports.com ... report to its pharmaceuticals section with historic and ... and much more. Complete report on ... pages, profiling 15 companies and supported with 261 ... http://www.reportsnreports.com/reports/601420-global-cell-culture-media-industry-2016-market-research-report.html . The Global Cell ...
Breaking Biology Technology: