Navigation Links
Oxygen depletion: A new form of ocean habitat loss

An international team of physical oceanographers including a researcher from Scripps Institution of Oceanography at UC San Diego has discovered that oxygen-poor regions of tropical oceans are expanding as the oceans warm, limiting the areas in which predatory fishes and other marine organisms can live or enter in search of food.

The new study is led by Lothar Stramma from the Leibniz Institute of Marine Sciences (IFM-GEOMAR) in Kiel, Germany, and is co-authored by Janet Sprintall, a physical oceanographer at Scripps Oceanography and others. The researchers found through analysis of a database of ocean oxygen measurements that levels in tropical oceans at a depth of 300 to 700 meters (985 to 2,300 feet) have declined during the past 50 years. The ecological impacts of this increase could have substantial biological and economical consequences.

We found the largest reduction in a depth of 300 to 700 meters (985 to 2,300 feet) in the tropical northeast Atlantic, whereas the changes in the eastern Indian Ocean were much less pronounced, said Stramma. Whether or not these observed changes in oxygen can be attributed to global warming alone is still unresolved. The reduction in oxygen may also be caused by natural processes on shorter time scales.

Sprintall said the oxygen-poor areas have the potential to move into coastal areas via currents that flow from the mid-depth tropical oceans, where the oxygen changes were observed, and along the west coast of continents.

The width of the low-oxygen zone is expanding deeper but also shoaling toward the ocean surface, said Sprintall, a specialist in observing changes of fluxes in ocean properties such as heat distribution.

Sprintall contributed data to the study gathered during recent cruises undertaken as part of the Climate Variability and Predictability (CLIVAR) program, a long-running study operated by the World Climate Research Programme that seeks to understand climate through ocean-atmosphere interactions.

The study, Expanding Oxygen-Minimum Zones in the Tropical Oceans, appears in the May 2 edition of the journal Science. The research team includes Stramma, Sprintall, NOAA scientist Gregory Johnson, and Volker Mohrholz from the Institute for Baltic Sea Research in Warnemnde, Germany.

The team selected ocean regions for which they could obtain the greatest amount of data to document the decline in oxygen. Some of the more recent data came from oxygen sensors which have been added to about 150 of the profiling floats used in Argo, a worldwide network of sensors that track basic ocean conditions such as temperature and salinity. There are more than 3,000 Argo floats operating in the worlds oceans, and Sprintall said the quality of the data gathered by the Argo floats suggests that more units in the network should be outfitted with oxygen sensors.

Lisa Levin, a biological oceanographer at Scripps Oceanography who studies oxygen-minimum zones that intercept the seafloor, said an expansion of oxygen-minimum zones in the oceans could lead to diminished biodiversity and to the expanded distributions of organisms that have adapted to live in hypoxic, or oxygen-poor waters.

I think its uncharted territory, said Levin, who was not affiliated with the study. Thicker oxygen minimum zones could affect nutrient cycling, predator-prey relationships and plankton migrations. Where the expanding oxygen-minimum zones impinge on continental margins, we could see huge ecosystem changes.


Contact: Rob Monroe or Mario Aguilera
University of California - San Diego

Related biology news :

1. Viruses, oxygen and our green oceans
2. Oregon researchers study widespread areas of low oxygen off northwest coast
3. Crew oxygen for ISS loaded on Jules Verne
4. Why diving marine mammals resist brain damage from low oxygen
5. Researchers detect hint of oxygen 50 to 100 million years earlier than first believed
6. Low oxygen in coastal waters impairs fish reproduction
7. Scripps Oceanography Research pegs ID of red tide killer
8. Researchers to develop ocean sanctuary noise budget to evaluate potential impact on marine mammals
9. Continents loss to oceans boosts staying power
10. Oceanic sharks worldwide at serious risk from high-seas fishing, rising demand for shark products
11. Giant ocean eddy shadows Sydney
Post Your Comments:
Related Image:
Oxygen depletion: A new form of ocean habitat loss
(Date:5/12/2016)... DALLAS , May 12, 2016 ... has just published the overview results from the Q1 ... of the recent wave was consumers, receptivity to a ... wearables data with a health insurance company. ... choose to share," says Michael LaColla , CEO ...
(Date:4/28/2016)... 2016 First quarter 2016:   ... with the first quarter of 2015 The gross margin ... (loss: 18.8) and the operating margin was 40% (-13) ... Cash flow from operations was SEK 249.9 M (21.2) , ... unchanged, SEK 7,000-8,500 M. The operating margin for 2016 ...
(Date:4/15/2016)... 2016  A new partnership announced today will ... decisions in a fraction of the time it ... high-value life insurance policies to consumers without requiring ... Force Diagnostics, rapid testing (A1C, Cotinine and HIV) ... pressure, weight, pulse, BMI, and activity data) available ...
Breaking Biology News(10 mins):
(Date:6/27/2016)... NC (PRWEB) , ... June 27, 2016 , ... ... just published their findings on what they believe could be a new and ... of the new research. Click here to read it now. , ...
(Date:6/27/2016)... Raleigh, NC (PRWEB) , ... June 27, 2016 ... ... a mission to bring innovative medical technologies, services and solutions to the healthcare ... development and implementation of various distribution, manufacturing, sales and marketing strategies that are ...
(Date:6/27/2016)... -- Liquid Biotech USA , Inc. ... Research Agreement with The University of Pennsylvania ("PENN") ... patients.  The funding will be used to assess ... outcomes in cancer patients undergoing a variety of ... to support the design of a therapeutic, decision-making ...
(Date:6/24/2016)... , June 24, 2016  Regular discussions on a range ... place between the two entities said Poloz. Speaking ... Ottawa , he pointed to the country,s inflation ... federal government. "In ... "Both institutions have common economic goals, why not sit down ...
Breaking Biology Technology: