Ocean Acidiﬁcation More Rapid in Coastal Oceans
"New research under the joint NCCOS Competitive Research Program and NOAA Ocean Acidification Program finds the combined effects of anthropogenic and biological carbon dioxide (CO2) inputs may lead to more rapid acidiﬁcation in Chesapeake Bay and other coastal water compared to the open ocean. The results indicate that eutrophication can exacerbate ocean acidification (OA) where animal and plant respiration contributes a far greater acidification in the coastal oceans relative to the open ocean. [...]"
Source: The National Centers for Ciastal Ocean Science
Taking a deep breath? Scientists measure unusually high oxygen uptake in the Labrador Sea
"The Labrador Sea in the North Atlantic is one of the few areas in the world ocean where cold, saline seawater sinks to large depths and forms deep water. This convection process also transports oxygen into the deep sea. A team of scientists from Scripps Institution of Oceanography (San Diego, California), Dalhousie University (Halifax, Canada) and GEOMAR Helmholtz Centre for Ocean Research Kiel have now published the analysis of data obtained from the mooring K1 in the international scientific journal Geophysical Research Letters. [...]"
Acid zone in Chesapeake Bay identified
"Zone of water 30 feet below surface is increasing in acidity, threatening shellfish.
A research team, led by University of Delaware professor Wei-Jun Cai, has identified a zone of water that is increasing in acidity in the Chesapeake Bay.
The team analyzed little studied factors that play a role in ocean acidification (OA)--changes in water chemistry that threaten the ability of shellfish such as oysters, clams and scallops to create and maintain their shells, among other impacts."
Study estimates oxygen loss in ancient global ocean
A loss of oxygen in global ocean seawater 94 million years ago led to a mass extinction of marine life that lasted for roughly half a million years.
Scientists have found several potential explanations for how the loss of oxygen happened. These could include enhanced volcanic activity, increased nutrients reaching the ocean, rising sea levels, and warming sea and surface temperatures. But to point a finger at any one cause (or several of them) requires knowing how fast the oxygen loss happened.
A new technique, developed by Arizona State University graduate student Chad Ostrander with colleagues at Wood Hole Oceanographic Institution (WHOI) and Florida State University (FSU), has put a timetable on the oxygen loss associated with this major ocean extinction event, which is known to science as Oceanic Anoxic Event 2.
Meat industry blamed for largest-ever 'dead zone' in Gulf of Mexico
"The global meat industry, already implicated in driving global warming and deforestation, has now been blamed for fueling what is expected to be the worst “dead zone” on record in the Gulf of Mexico.
Toxins from manure and fertiliser pouring into waterways are exacerbating huge, harmful algal blooms that create oxygen-deprived stretches of the gulf, the Great Lakes and Chesapeake Bay, according to a new report by Mighty, an environmental group chaired by former congressman Henry Waxman. [...]"
Source: The Guardian
Gulf of Mexico ‘dead zone’ is the largest ever measured
"Scientists have determined this year’s Gulf of Mexico “dead zone,” an area of low oxygen that can kill fish and marine life, is 8,776 square miles, an area about the size of New Jersey. It is the largest measured since dead zone mapping began there in 1985."
Source: National Oceanic and Atmospheric Administration (NOAA)
Fossil site shows impact of early Jurassic's low oxygen oceans
Using a combination of fossils and chemical markers, scientists have tracked how a period of globally low ocean-oxygen turned an Early Jurassic marine ecosystem into a stressed community inhabited by only a few species.
Source: Science Daily
Report: High seas in high danger as ecological tipping point nears
"As delegates convene at the United Nations to work out an international treaty to preserve the biodiversity of the high seas, a new report underscores the need to protect the remote ocean.
Scientists at Oxford University in the United Kingdom reviewed 271 research papers published between 2012 and 2017 and synthesized the latest data on the impact of climate change, fishing and pollution on the high seas. Their findings are not encouraging: Even the most distant reaches of the ocean are suffering from chemical and plastic contamination, a loss of biodiversity and the consequences of rising temperatures. [...]"
Massive Bloom Of Pickle-Shaped Sea Creatures Fills The Pacific
"Millions of tubular sea creatures called pyrosomes have taken over the Pacific Ocean in an unprecedented bloom that has scientists baffled.
These bumpy, translucent organisms look like sea cucumbers that range in size from six inches to more than two feet long. But they’re actually made up of hundreds of tiny animals knit together with tissue into a filter-feeding cylinder. [...]
No one knows what the effects of the bloom will be, but scientists worry that if all the creatures die off at once they could sink to the seafloor and suck up all the oxygen as they’re decomposing, creating a dead zone for marine life."
NOAA, USGS and partners predict larger summer ‘dead zone’ for the Chesapeake Bay
"Scientists expect this year’s summer Chesapeake Bay hypoxic or “dead zone” — an area of low to no oxygen that can kill fish and aquatic life — will be larger than average, approximately 1.89 cubic miles, or nearly the volume of 3.2 million Olympic-size swimming pools.
Measurements for the Bay’s dead zone go back to 1950, and the 30-year mean maximum dead zone volume is 1.74 cubic miles. [...]"
Source: U.S. Geological Survey