Saturday 9 May 2015

A digest of climate change-related stories - 0508/2015

Ocean dead zone near African coast shows lowest oxygen levels ever recorded
dead zone, eddy, African dead zone, Atlantic dead zone, water pollution, damaged marine life, killing marine life, marine life destruction, agricultural runoff, fertilizer runoff

5 May, 2015

The dead zones are spreading. No, it’s not a sign of the zombie apocalypse, though the consequences could be just as dire. A recent study by the European Geosciences Union’s journal Biogeosciences describes a dead zone off the coast of Africa which contains the lowest levels of oxygen ever observed in the Atlantic. To complicate matters, the Atlantic-African dead zone is on the move, threatening all life in its path.

Often located in coastal waters, dead zones are caused by the runoff of chemicals and fertilizers used in agriculture, though poorly designed disposal of liquid human waste also contributes to the problem. A particularly infamous zone lurks in the Gulf of Mexico, a deadly consequence to farming runoff down the Mississippi River. Nitrogen and phosphorus rich runoff settles in river deltas or in the ocean, where it feeds the growth of algal blooms. As the algae dies, it becomes food for bacteria, which in turn consumes the oxygen present in the water. This environment is extremely inhospitable to marine life. Oxygenless water is usually diluted by current and tidal movement, yet the presence of enormous eddies in the Atlantic-African dead zone prevents this dispersal.


The fast rotation of the eddies makes it very difficult to exchange oxygen across the boundary between the rotating current and the surrounding ocean. Moreover, the circulation creates a very shallow layer – of a few tens of meters – on top of the swirling water that supports intense plant growth,” says Johannes Karstensen, lead author of the report. “From our measurements, we estimated that the oxygen consumption within the eddies is some five times larger than in normal ocean conditions.”ithin the eddies is some five times larger than in normal ocean conditions.”


Gulf Coast, Gulf Coast dead zone, Louisiana dead zone, Gulf of Mexico dead zone

Eddies slowly move westward and if these particular eddies make landfall, it would spell disaster for the local marine ecosystem. “Given that the few dead zones we observed propagated less than 100 km north of the Cape Verde archipelago, it is not unlikely that an open-ocean dead zone will hit the islands at some point. This could cause the coast to be flooded with low-oxygen water, which may put severe stress on the coastal ecosystems and may even provoke fish kills and the die-off of other marine life,” says Karstensen.

The outlook is not all doom and gloom. Dead zones can be rehabilitated, as demonstrated by the transformation of the Black Sea dead zone. Previously the largest in the world, the Black Sea dead zone disappeared in the decade following the collapse of the Soviet Union, which made fertilizers cost prohibitive for farmers. Although this revitalization was coincidental, deliberate efforts have been made to eliminate dead zones along the Hudson River and in San Francisco Bay. However, no clean-up will be able to revive now-extinct organisms that have perished in the dead zone.



Military Could Step in Over Brazil Drought Chaos



5 May, 2015


An engineer for Sao Paulo state’s water company said that “scenes from the end of the world” would ensue if the city ran out of water. The drought in the Brazilian metropolis of Sao Paulo has become so severe that local authorities are considering bringing in military personnel to cope with the possible social chaos.

With over 11 million residents, Sao Paulo is Brazil's most populous city and the country's economic center. But senior officials at Sao Paulo's water facility said residents might soon be evacuated because there is not enough water, to bathe or to clean homes.

The water crisis is the worst is the last 84 years, and the dry season has only just begun, with less water in the dams than in 2014, when restrictions on water began and the authorities began to realize the seriousness of the disaster.

Last week, a conference between academics, military employees and local councils to discuss how to handle the coming five months in the case that reserves run out, and the city might go up to five days without water.

Paulo Massato, engineer at the state water company, told the conference that water supplies could run out as early as July, if emergency works are not finished in time.


Engineers are working to create infrastructure to connect various reservoirs, which, if completed, would mean that there would be enough water to last until October.

On being asked what would happen in the worst case scenario, with no rain and incomplete works, Massato replied, “It would be terrible. No would be no food, no would be no electricity … It would be a scene from the end of the world.

There a thousands of people, and it could cause social chaos. It would not only be a problem of water shortage, it would be much more than that.” Last year the smaller city of Itu suffered a similar





April 2015 Arctic sea ice is second-lowest on record



This is the Agham fluvial terrace, located roughly 400 m above the current river level of the upper Shyok valley, NW Himalayas, India. See related article by J.H. Blöthe and colleagues.


Large landslides are an important process of erosion in the Himalaya-Karakoram ranges. These high-relief landscapes are characterized by steep slopes that are prone to frequent landsliding. By mapping nearly 500 large (greater than 0.1 km2) landslides in the HKR, geologists have found that the vast majority of these mass movements lie in the lower portions of the landscape, whereas glaciers and rock glaciers occupy the higher elevations almost exclusively.




A Canadian advisory panel on Wednesday approved a plan to bury nuclear waste at a site just steps away from Lake Huron, saying it had concluded the project would pose no danger to the environment.

The Joint Review Panel made its recommendation in a report to Canada's environment minister, Leona Aglukkaq, who is expected to issue a decision within 120 days.



The forest fire near Chernobyl that broke out a week ago has spread radionuclides, notably plutonium, over eastern Europe, Asia, Alaska, and is now moving in over the west coast of the US.

This image from the downloaded Windows HYSPLIT atmospheric dispersion model shows the spread of this plume, as of 2 PM Eastern time on May 7.

And the world's climate change deniers



The Australian government gave a 4 million dollar grant to set up a denialist centre in WA, to he headed by Bjørn Lomborg 


Australia’s education minister, Christopher Pyne, has vowed to find another university to host the Bjorn Lomborg “consensus centre” and is seeking legal advice about a decision by the University of Western Australia (UWA) to hand back $4m in federal government funding awarded for it.

UWA handed back the funding and dropped its connection with Lomborg, saying that lack of support among its academics made the centre untenable.


Scientists weigh up new evidence on Antarctic ice melt



What If Humans Disappeared?




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