Navigation Links
Humans 'damaging the oceans'
Date:7/29/2009

Mounting evidence that human activity is changing the world's oceans in profound and damaging ways is outlined in a new scientific discussion paper released today.

Man-made carbon emissions "are affecting marine biological processes from genes to ecosystems over scales from rock pools to ocean basins, impacting ecosystem services and threatening human food security," the study by Professor Mike Kingsford of the ARC Centre of Excellence for Coral Reef Studies and James Cook University and colleague Dr Andrew Brierley of St Andrews University, Scotland, warns.

Their review, published in the latest issue of the journal Current Biology, says that rates of physical change in the oceans are unprecedented in some cases, and change in ocean life is likely to be equally quick.

These include changes in the areas fish and other sea species can inhabit, invasions, extinctions and major shifts in marine ecosystems.

"In the past, the boundaries between geological ages are marked by sudden losses of species. We may now be entering a new age in which climate change and other human-caused factors such as fishing are the major threats for the oceans and their life," Andrew and Mike say.

"Given how essential the oceans are to how our entire planet functions it is vital that we intervene before more tipping points are passed and the oceans go down the sort of spiral of decline we have seen in the world's tropical forests and rangelands, for example."

Man-made carbon emissions are now above the 'worst case' scenario envisioned by the Intergovernmental Panel on Climate Change (IPCC), causing the most rapid global warming seen since the peak of the last Ice Age. At the same time the carbon is acidifying the oceans, with harmful consequences for certain plankton and shellfish.

"At current emission rates it is possible we will pass the critical level of 450 parts per million CO2 in the atmosphere by 2040. That's the level when, it is generally agreed, global climate change may become catastrophic and irreversible," they add. "At that point we can expect to see the loss of most of our coral reefs and the arctic seas."

"The climate is currently warming faster than the worst case known from the fossil record, about 56 million years ago, when temperatures rose about 6 degrees over 1000 years. If emissions continue it is not unreasonable to expect warming of 5.5 degrees by the end of this century."

Scientists expect ocean oxygen levels to decline by about six per cent for every one degree increase in temperature and areas in the sea which are low in oxygen to grow by at least 50 per cent. This has major implications for the world's most productive fishing waters in the cool temperate regions. The seas provide around one sixth of humanity's protein food and any loss in fisheries production will have a direct impact on us, he adds.

Besides the changes induced by carbon emissions, the oceans are also under assault from over-fishing, increased UV exposure, toxic pollution, alien species and disease. The combined effect is to weaken the ability of many species to withstand these multiple stresses.

Another risk is that warming will unlock vast reserves of frozen methane in the seabed, triggering uncontrollable, runaway global warming.

"In the face of such terrifying changes even large scale interventions such as establishment of very large networks of Marine Protected Areas are unlikely to be effective," Mike cautions. "On a global scale, an immediate reduction in CO2 emissions is essential to minimize future human-induced climate change."

The oceans can also play a role in the proposed solution of eliminating carbon emissions, by producing clean energy from wind, wave and tide potentially by triggering phytoplankton blooms with fertilisers to absorb more carbon from the atmosphere, or using the seabed to store CO2. However these require far more research to be sure.

"It may already be too late to avoid major irreversible changes to many marine ecosystems. As history has shown us, these marine-based changes could have major earth-system consequences," the scientists conclude.


'/>"/>

Contact: Michael Kingsford
Michael.Kingsford@jcu.edu.au
61-747-814-345
ARC Centre of Excellence in Coral Reef Studies
Source:Eurekalert

Related biology news :

1. Humans lend a hand to critically endangered waterbird
2. Ants more rational than humans
3. First direct evidence of substantial fish consumption by early modern humans in China
4. Dogs, humans, put heads together to find cure for brain cancer
5. Humans related to orangutans, not chimps, says new Pitt, Buffalo Museum of Science study
6. Test detects molecular marker of aging in humans
7. Researchers shed light on trading behavior in animals -- and humans
8. Geography and history shape genetic differences in humans
9. Zebrafish provide a model for cancerous melanoma in humans
10. Bolivian rainforest study suggests feeding behavior in monkeys and humans have ancient, shared roots
11. Opposites attract -- how genetics influences humans to choose their mates
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:3/1/2017)...  Aware, Inc. (NASDAQ: AWRE), a leading supplier of ... Moberg has resigned, effective March 3, 2017, as ... and Treasurer of Aware citing a desire to retire.  ... of the Board of Directors of Aware. ... and co-President, General Counsel has been named Chief Executive ...
(Date:2/26/2017)... -- Securus Technologies, a leading provider of civil and ... corrections and monitoring, announces the appointment of a ... often, too many offenders return to jail or ... to tackle this ongoing problem and improve the ... significant steps are underway, Securus continues to invest ...
(Date:2/16/2017)... , Feb. 16, 2017  Genos, a ... announced that it has received Laboratory Accreditation from ... Accreditation is presented to laboratories that meet stringent ... demonstrate scientifically rigorous processes. "Genos is ... in laboratory practices. We,re honored to be receiving ...
Breaking Biology News(10 mins):
(Date:3/29/2017)... 29, 2017 Research and Markets has ... and Global Markets" report to their offering. ... The study ... sequencing, biochips, RNA interference, synthetic biology tools and genome editing ... These technologies and products are analyzed to determine ...
(Date:3/28/2017)... ... 2017 , ... NetDimensions announced today that Scandinavian Health Limited ... management for consistent implementation of standards and regulatory requirements across SHL companies worldwide. ... improve and streamline their training and employee development programs, which are critical to ...
(Date:3/28/2017)... ... March 28, 2017 , ... Benchworks announced that ... Philadelphia. The event was offered by the Chamber of Commerce for Greater Philadelphia ... groups and interaction with speakers who are leaders in their industries. Topics included ...
(Date:3/28/2017)... March 28, 2017 Summary This ... Enzo Biochem and its partnering interests and activities since 2010. ... provides an in-depth insight into the partnering activity of one ... demand company reports are prepared upon purchase to ensure inclusion ... The report will be delivered in PDF format ...
Breaking Biology Technology: