Navigation Links
Ocean geoengineering scheme no easy fix for global warming
Date:2/18/2010

Pumping nutrient-rich water up from the deep ocean to boost algal growth in sunlit surface waters and draw carbon dioxide down from the atmosphere has been touted as a way of ameliorating global warming. However, a new study led by Professor Andreas Oschlies of the Leibniz Institute of Marine Sciences (IFM-GEOMAR) in Kiel, Germany, pours cold water on the idea.

"Computer simulations show that climatic benefits of the proposed geo-engineering scheme would be modest, with the potential to exacerbate global warming should it fail," said study co-author Dr Andrew Yool of the National Oceanography Centre, Southampton (NOCS).

If international governmental policies fail to reduce emissions of carbon dioxide to levels needed to keep the impacts of human-induced climate change within acceptable limits it may necessary to move to 'Plan B'. This could involve the implementation of one or more large-scale geo-engineering schemes proposed for reducing the carbon dioxide increase in the atmosphere.

One possible approach is to engineer the oceans to facilitate the long-term sequestration of carbon dioxide from the atmosphere. It has been suggested that this could be done by pumping of nutrient-rich water from a depth of several hundred metres to fertilize the growth of phytoplankton, the tiny marine algae that dominate biological production in surface waters.

The aim would be to mimic the effects of natural ocean upwelling and increase drawdown of atmospheric carbon dioxide by phytoplankton through the process of photosynthesis. Some of the sequestered carbon would be exported to the deep ocean when phytoplankton die and sink, effectively removing it from the system for hundreds or thousands of years.

A previous study, of which Yool was lead author, used an ocean general circulation model to conclude that literally hundreds of millions of pipes would be required to make a significant impact on global warming. But even if the technical and logistical difficulties of deploying the vast numbers of pipes could be overcome, exactly how much carbon dioxide could in principle be sequestered, and at what risk?

In the new study, the researchers address such questions using a more integrated model of the whole Earth system. The simulations show that, under most optimistic assumptions, three gigatons of carbon dioxide per year could be captured. This is under a tenth of the annual anthropogenic carbon dioxide emissions, which currently stand at 36 gigatons per year. A gigaton is a million million kilograms.

One surprising feature of the simulations was that the main effect occurred on land rather than the ocean. Cold water pumped to the surface cooled the atmosphere and the land surface, slowing the decomposition of organic material in soil, and ultimately resulting in about 80 per cent of the carbon dioxide sequestered being stored on land. "This remote and distributed carbon sequestration would make monitoring and verification particularly challenging," write the researchers.

More significantly, when the simulated pumps were turned off, the atmospheric carbon dioxide levels and surface temperatures rose rapidly to levels even higher than in the control simulation without artificial pumps. This finding suggests that there would be extra environmental costs to the scheme should it ever need to be turned off for unanticipated reasons.

"All models make assumptions and there remain many uncertainties, but based on our findings it is hard to see the use of artificial pumps to boost surface production as being a viable way of tackling global warming," said Yool.


'/>"/>

Contact: Dr. Rory Howlett
r.howlett@noc.soton.ac.uk
44-238-059-8490
National Oceanography Centre, Southampton (UK)
Source:Eurekalert  

Related biology news :

1. Canadian ocean science in the spotlight at AAAS 2010
2. Oceans reveal further impacts of climate change, says UAB expert
3. Bubble physicist counts bubbles in the ocean to answer questions about climate, sound, light
4. Melting tundra creating vast river of waste into Arctic Ocean
5. Glacial watersheds may contribute to oceanic food web
6. Zoning the ocean may help endangered whales to recover
7. Oceans day at International Climate Change Conference
8. Beyond sunlight: Explorers census 17,650 ocean species between edge of darkness and black abyss
9. Paleontologists find extinction rates higher in open-ocean settings during mass extinctions
10. SEA to conduct expedition dedicated to measuring plastic marine debris in the North Atlantic Ocean
11. North Atlantic fish populations shifting as ocean temperatures warm
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Ocean geoengineering scheme no easy fix for global warming
(Date:3/23/2016)... 2016 Einzigartige ... und Stimmerkennung mit Passwörtern     ... MESG ), ein führender Anbieter digitaler Kommunikationsdienste, ... SpeechPro zusammenarbeitet, um erstmals dessen Biometrietechnologie einzusetzen. ... Möglichkeit angeboten, im Rahmen mobiler Apps neben ...
(Date:3/17/2016)... LONDON , March 17, 2016 ... market intelligence, forecasts the global biometrics market will ... an impressive 118% increase from 2015. Consumer electronics, ... with embedded fingerprint sensors anticipated to reach two ... Dimitrios Pavlakis , Research Analyst ...
(Date:3/11/2016)... Germany , March 11, 2016 http://www.apimages.com ... - Cross reference: Picture is available at AP Images ( http://www.apimages.com ... from DERMALOG will be used to produce the new refugee identity ... other biometric innovations, at CeBIT in Hanover ... scanner from DERMALOG will be used to produce the new refugee ...
Breaking Biology News(10 mins):
(Date:5/23/2016)... (PRWEB) , ... May 23, 2016 , ... ... interest organization focused on molecular nanotechnology, announced the winners for the 2015 Foresight ... physicist Richard Feynman, are given in two categories, one for experiment and the ...
(Date:5/20/2016)... , ... May 20, 2016 , ... Kablooe Design, a ... companies, today announced its official 25th anniversary of the business. “We have worked hard ... grateful to our customers for the privilege and honor of serving their product design ...
(Date:5/19/2016)... ... , ... Anton Paar USA, located in Ashland, Virginia is pleased to announce ... structure adds a third office building to the current facilities. , Growth is ... land, along with office space adjacent to the previous main building. Through remodels and ...
(Date:5/19/2016)... ... May 19, 2016 , ... ... (CRO) has welcomed Abu Siddiqui as Director, Large Molecule & Biomarker Bioanalysis. , ... vaccine and translational biomarker discovery studies for preclinical and clinical safety programs. “We’ve ...
Breaking Biology Technology: