Flooding Makes Big 'Dead Zone' Off Louisiana Coast Likely
"The year's widespread flooding has made it likely that a big, oxygen-starved "dead zone" off Louisiana's coast will form this summer, the head of the National Centers for Coastal Ocean Science said Thursday. Preliminary computer model runs "indicate a large to very large year," for the area where there's too little oxygen to support marine life, Steven Thur told the Mississippi River/Gulf of Mexico Hypoxia Task Force during a meeting livestreamed from Baton Rouge. [...]"
Source: The New York Times
Sri Lanka's marine protection agency calls for tougher laws against ocean pollution
General Manager of the Marine Environment Protection Authority, Dr. P.B. Teney told Xinhua that authorities had discovered the formation of a dead zone in the Bay of Bengal which had spread across a 6000 square kilometer area and was 100 meters to 400 meters in depth. [...]"
'Dead zone' volume more important than area to fish, fisheries
Dubravko Justic, the Texaco Distinguished Professor in the LSU Department of Oceanography & Coastal Sciences, and Research Associate Lixia Wang recently co-authored a study suggesting that measuring the volume rather than the area of the Gulf of Mexico's dead zone, is more appropriate for monitoring its effects on marine organisms.
"The dead zone, a hypoxic zone, is a region of low oxygen that results from runoff of high nutrients, such as nitrogen and phosphorus, often found in fertilizer, flowing from the Mississippi River into the coastal ocean. It is the largest recurring hypoxic zone in the U.S., occurring most summers, and is located off the coast of Louisiana. This nutrient pollution, coupled with other factors, is believed to have a negative impact on fisheries because it depletes the oxygen required to support most marine life in bottom and near-bottom waters. [...]"
Source: Science Daily
Job Offer: Postdoctoral Researcher
Postdoctoral Researcher in the area of ocean physical and biogeochemical coupling to work with Professor Resplandy in the Princeton University Geosciences department. The postdoc will investigate the physical and biological processes at both global and local scale that control the evolution of the tropical Oxygen Minimum Zone in the Indian Ocean. Details of the project can be found at https://environment.princeton.edu/grandchallenges/research/energy/dead_zones. Ideally, candidates will have a strong background in numerical modeling, but candidates with the necessary background in geophysical fluid dynamics and/or ocean biogeochemistry will be given full consideration.
Applicants should include a cover letter, a curriculum vitae including a publication list, and contact information for three references by applying at https://www.princeton.edu/acad-positions/position/9941. Applications should be received by April 15, 2019.
Tool to Capture Marine Biological Activity Gets Coastal Upgrade
"Upwelling hinders an efficient method to estimate a key measure of biological productivity in coastal waters, but accounting for surface temperatures could boost accuracy.
Although coastal waters make up only about 10% of the surface area of the ocean, they harbor most of its life. Measuring biological activity in these regions can reveal their impact on fisheries, low-oxygen dead zones, and the global carbon cycle, but coastal zones remain understudied. Now new research by Teeter et al. suggests how to improve the accuracy of a method that uses oxygen and argon measurements to quickly estimate marine biological activity. [...]"
Characterization of “dead-zone” eddies in the eastern tropical North Atlantic (2016)
"Localized open-ocean low-oxygen “dead zones” in the eastern tropical North Atlantic are recently discovered ocean features that can develop in dynamically isolated water masses within cyclonic eddies (CE) and anticyclonic mode-water eddies (ACME). Analysis of a comprehensive oxygen dataset obtained from gliders, moorings, research vessels and Argo floats reveals that “dead-zone” eddies are found in surprisingly high numbers and in a large area from about 4 to 22°N, from the shelf at the eastern boundary to 38°W. [...]"
Authors: Florian Schütte et al.
Expanding 'dead zone' in Arabian Sea raises climate change fears
In the waters of the Arabian Sea, a vast "dead zone" the size of Scotland is expanding and scientists say climate change may be to blame. In his lab in Abu Dhabi, Zouhair Lachkar is labouring over a colourful computer model of the Gulf of Oman, showing changing temperatures, sea levels and oxygen concentrations.His models and new research unveiled earlier this year show a worrying trend.Dead zones are areas of the sea where the lack of oxygen makes it difficult for fish to survive and the one in the Arabian Sea is "is the most intense in the world," says Lachkar, a senior scientist at NYU Abu Dhabi in the capital of the United Arab Emirates.
Chesapeake Bay: Larger-than-average summer 'dead zone' forecast for 2018 after wet spring
This summer's Chesapeake Bay hypoxic or dead zone, an area of low to no oxygen that can kill fish and other aquatic life, is expected to be about 1.9 cubic miles (7.9 cubic kilometers), according to the forecast released today by the two universities. [...]"
Gulf of Mexico 'dead zone' forecasted to exceed the size of Connecticut
"Scientists have predicted the dead zone, or area with little to no oxygen in the northern Gulf of Mexico, will become larger than the state of Connecticut by the end of July. The dead zone will cover about 6,620 square miles of the bottom of the continental shelf off Louisiana and Texas. While there are more than 500 dead zones around the world, the northern Gulf of Mexico dead zone is the second largest human-caused coastal hypoxic area in the world."
Physical controls on oxygen distribution and denitrification potential in the north west Arabian Sea
"At suboxic oxygen concentrations, key biogeochemical cycles change and denitrification becomes the dominant remineralization pathway. Earth system models predict oxygen loss across most ocean basins in the next century; oxygen minimum zones near suboxia may become suboxic and therefore denitrifying. Using an ocean glider survey and historical data, we show oxygen loss in the Gulf of Oman (from 6‐12 to < 2 μmol kg‐1) not represented in climatologies. [...]"
Source: Grophysical Research Letters
Authors: B. Y. Queste et al.