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Acidification des océans

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Can we just drown our carbon emissions in the ocean? By Eve Andrews on Sep 17, 2020 at 3:58 am. Q.

Can we just drown our carbon emissions in the ocean? By Eve Andrews on Sep 17, 2020 at 3:58 am

Dear Umbra, Is there a maximum amount of CO2 that the ocean can absorb? What will be the effects should this happen? — Some Questions Underestimate Imminent Doom A. Once you learn how many of the various expressions of climate change — drought, hurricanes, even wildfires — have to do with fluctuations in the ocean, it’s hard to stop thinking about it. But understanding marine fluctuations — and their effects on dry land — requires some grasp of several scientific concepts that, if you’re anything like me, you haven’t thought about since high school. I’m not a fish. Why should coral reefs matter to me? By Eve Andrews on Jul 30, 2020.

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I’m not a fish. Why should coral reefs matter to me? By Eve Andrews on Jul 30, 2020

Dear Umbra, Aside from scuba-diving boredom, what will a world without coral reefs look like and how will it affect my day-to-day life? — Does Indifference Void Environmental Responsibility? A. Dear DIVER, I’ve never seen a coral reef. Le Pacifique : un océan de solutions Polynésie : sauvons les perles ! Le 18 juillet 2020. Les coraux confrontés à « un niveau de menace significatif » dans les îles françaises de l’océan Indien. Les coraux sont confrontés à « un niveau de menace significatif » dans les îles françaises de l’océan Indien : 15 % de ces espèces sont en danger à La Réunion, 12 % à Mayotte et 6 % dans les îles Éparses, affirme le comité français de l’Union internationale pour la conservation de la nature (UICN). « Le réchauffement climatique figure au rang des principales menaces », explique-t-il dans un état des lieux inédit paru ce jeudi et mené conjointement avec l’Office français de la biodiversité (OFB) et le Muséum national d’Histoire naturelle (MNHN).

Les coraux confrontés à « un niveau de menace significatif » dans les îles françaises de l’océan Indien

Australie : La Grande Barrière de corail a vécu son pire épisode de blanchissement. Avec l’été austral qui vient de s’achever, la Grande Barrière de corail a vécu son plus grave épisode de blanchissement de coraux, ont annoncé des chercheurs australiens, ce mardi, estimant que le réchauffement climatique menaçait la survie même de ce joyau australien classé au Patrimoine mondial.

Australie : La Grande Barrière de corail a vécu son pire épisode de blanchissement

Australie : La Grande Barrière est gravement touchée par le blanchissement de ses coraux. Replay 13h15, le dimanche... - Planète Fragile : récif en danger. To save our oceans, we have to change what we do on land. For decades, oceans have served as the planet’s carbon garbage dump, soaking up 90 percent of the excess atmospheric heat generated since 1970 and a third of our greenhouse gas emissions.

To save our oceans, we have to change what we do on land

Now the 71 percent of the Earth that makes life on land possible has reached a frightening tipping point that threatens human existence, according to a landmark report issued Wednesday by the United Nations-supported Intergovernmental Panel on Climate Change, or IPCC. The findings suggest severe consequences for both humanity and nature, according to Ko Barrett, the panel’s vice chair, who spoke at a press briefing on Tuesday. “This report highlights the urgency of timely, ambitious, coordinated and enduring action,” said Barrett, who is also the deputy assistant administrator of oceanic and atmospheric research at the U.S. National Oceanic and Atmospheric Administration. Scientists create a new guide for saving corals in a warming world. À cause du manque d'oxygène dans les océans, les invertébrés marins deviennent aveugles. La désoxygénation des océans liée aux émissions de gaz à effet de serre a des conséquences (tristement) inattendues : des chercheurs ont découvert qu’un faible taux d’oxygène dans la mer entraîne une cécité temporaire chez certains invertébrés marins.

À cause du manque d'oxygène dans les océans, les invertébrés marins deviennent aveugles

La diminution du taux d’oxygène dans les océans n’aurait pas pour seule conséquence d’empêcher la faune marine de respirer… Elle l’empêcherait également de voir. Des chercheurs de l’institut océanographique Scripps de San Diego, aux Etats-Unis, ont publié une étude* dont les résultats indiquent que de faibles niveaux d'oxygène dans l'eau de mer pourraient aveugler certains invertébrés marins (mollusques et crustacés). Une découverte inédite : c’est la première fois que l’on parvient à démontrer que la vision des invertébrés marins est sensible à la quantité d’oxygène disponible dans l’eau (on connaissait déjà le phénomène chez l’homme et les animaux terrestres lié au manque d'oxygène dans l'air). La vue, un sens primordial.

À cause des gaz à effet de serre, les poissons qui chassent en eaux profondes sont privés d'oxygène. Our-oceans-are-gasping-for-breath-and-we-ignore-it-at-our-peril. DO Oxygen Solubility Table. West Coast shores are bathed in ocean acidification “hot spots” As atmospheric carbon dioxide levels have risen (in red), the ocean has absorbed some of that CO2 (in green), lowering its pH (in blue). NOAA. World's oceans facing biggest coral die-off in history, scientists warn.

Scientists have confirmed the third-ever global bleaching of coral reefs is under way and warned it could see the biggest coral die-off in history.

World's oceans facing biggest coral die-off in history, scientists warn

Since 2014, a massive underwater heatwave, driven by climate change, has caused corals to lose their brilliance and die in every ocean. By the end of this year 38% of the world’s reefs will have been affected. About 5% will have died forever. The Great Barrier Reef has been brutally bleached for the second year in a row. Contrary to what you may have heard, the reef isn’t dead — not yet.

The Great Barrier Reef has been brutally bleached for the second year in a row.

But aerial surveys show that 900 miles of the 1,400-mile-long reef have been severely bleached in the past two years. Bleaching occurs when warm water causes stressed-out corals to expel symbiotic algae from their tissues; corals then lose their color and their chief source of food, making them more likely to die. Last year’s El Niño–induced bleaching event was devastating, knocking out two-thirds of the corals in the northern section of the reef.

We’d hoped that 2017 would bring cooler temperatures, giving the fragile ecosystem some much needed R&R. Think you’ve had it rough this past year? You should hear what the Great Barrier Reef is dealing with. According to the cover article in today’s issue of the journal Nature, the iconic reef off the coast of Australia suffered unprecedented coral die-off after last year’s record-breaking bleaching event.

Think you’ve had it rough this past year? You should hear what the Great Barrier Reef is dealing with.

Now, as the Southern Hemisphere hits late summer temperatures, central and southern sections of the reef — areas which avoided the worst of last year’s bleaching — are in trouble. “We didn’t expect to see this level of destruction to the Great Barrier Reef for another 30 years,” coral researcher Terry Hughes told the New York Times. Hughes led the team that conducted aerial surveys to document the bleaching last year, as well as subsequent surveys to assess just how much of that bleaching turned into dying. Bleached corals don’t always turn into dead corals — some are able to recover when temperatures drop. Oceans are about to turn into a frothing cauldron of death. Mustafa Ali helped to start the EPA’s environmental justice office and its environmental equity office in the 1990s.

Oceans are about to turn into a frothing cauldron of death.

For nearly 25 years, he advocated for poor and minority neighborhoods stricken by pollution. As a senior adviser and assistant associate administrator, Ali served under both Democratic and Republican presidents — but not under President Donald Trump. Acidification des océans : cartographie d'un phénomène 10 fois plus rapide qu'il y a 56 millions d'années. 18 510 lectures / 16 commentaires18 novembre 2014 ; révision : 16 juin 2015, 13 h 51. Dungeness crabs threatened by, you guessed it, climate change. When it comes to American culinary institutions, the Dungeness crabs that are hauled ashore from California to Washington state every winter season are the crustacean equivalents of apple pie.

The bountiful crab meat is a holiday staple in the San Francisco Bay Area and beyond. When crabbing was suspended in the fall by an algae outbreak, journalists flocked to docks to produce lead news stories — just as they did when crabbing was restricted following a 2007 oil spill. Research published this month could give a crab connoisseur a case of acid reflux. Scientists reported in the journal Marine Biology that ocean acidification, which is caused when carbon dioxide pollution dissolves into oceans, can kill and stunt young crabs, potentially jeopardizing whole populations. Scientists grew eggs and larvae from Puget Sound crabs in water containing pH resembling current and future conditions.

West Coast waters are more prone to acidification than other regions. Page 7 of The Point of No Return: Climate Change Nightmares Are Already Here. Historians may look to 2015 as the year when shit really started hitting the fan. Some snapshots: In just the past few months, record-setting heat waves in Pakistan and India each killed more than 1,000 people. In Washington state's Olympic National Park, the rainforest caught fire for the first time in living memory. London reached 98 degrees Fahrenheit during the hottest July day ever recorded in the U.K.; The Guardian briefly had to pause its live blog of the heat wave because its computer servers overheated. Will EPA Heed the Pope's Call to Save Our Oceans? When it comes to saving our oceans, I'm wondering: What would Pope Francis do?

With his sprawling encyclical on the fate of our planet this month, the pope became an unexpected revolutionary. I never thought I'd see bold environmental leadership arise from this powerful, historically conservative institution. By now, everyone knows about his call to fight climate change, ocean acidification, pollution and loss of the planet's biodiversity. Pope Francis opened a unique opportunity for a renewed environmental movement with his landmark encyclical Laudato Si, or "On Care for our Common Home. " J-P Gattuso : "L'acidité de l'océan pourrait tripler d'ici 2100"

Watch us explain ocean acidification with a soda maker. Now we can watch the oceans acidify in real time. How will ocean acidification impact marine life? Many marine organisms—such as coral, clams, mussels, sea urchins, barnacles, and certain microscopic plankton—rely on equilibrated chemical conditions and pH levels in the ocean to build their calcium-based shells and other structures. A new analysis published in the journal Environmental Science and Technology provides a holistic analysis of how species will be affected worldwide under different climate scenarios. "Calcifying species are indispensable for ecosystems worldwide: they provide nursery habitats for fish, food for marine predators, and natural defenses for storms and erosion. These species are also particularly vulnerable to ocean acidification triggered by increased fossil fuel emissions," says IIASA researcher Ligia Azevedo, who led the study.

Get ready for endlessly gross shrimp, thanks to climate change. Hard out here for a shrimp You may not think you care much about the mental well-being of imperiled sea spawn, but did ya know that a stressed-out shrimp does not a delicious cocktail make? According to a study published in November by Sweden’s University of Gothenburg, shrimp grown in acidic waters simply aren’t as tasty as those reared in healthy seas.

Ocean Roundup: Map Reveals Ocean Acidification Hotspots, Illegal Sea Urchin Harvesting Causing Alarm in St. Lucia, and More. Ocean acidification slurps up oysters. Editor’s note: We’re publishing a series from The Story Group that shows Americans on the front lines of climate change. The videos put faces to the warnings in the latest National Climate Assessment. “The ocean is so acidic that it is dissolving the shells of our baby oysters,” says Diani Taylor of Taylor Shellfish Farms in Shelton, Wash. She and her cousin Brittany are fifth-generation oyster farmers, and are grappling with ocean waters that are more acidic and corrosive than their fathers, grandfathers, and great-grandfathers knew.

Arctic Species at Risk from Increasing Ocean Acidity from Rising Carbon Dioxide. First Posted: Dec 03, 2013 08:41 AM EST Cyclones can whip up water and wind, creating conditions that can impact local climate and conditions. Now, scientists have discovered that far more of these wind storms spin across the Arctic than previously thought. It turns out that 1,900 churned across the top of the world from 2000 to 2010, leaving warm water and air in their wakes and melting sea ice in the Arctic Ocean. (Photo : Reuters) As carbon dioxide levels continue to rise, our oceans are facing a major threat. Like Us on Facebook As CO2 in our atmosphere continues to increase, seawater continues to absorb this gas.

Ocean acidification could be creating friendless fish. Quand les océans deviennent acides. How can we deal with ocean acidification? Step one: Study it. Don’t you love soda makers? You push a bottle of plain ol’ tap water up to a nozzle that spurts CO2 into your water, making it bubbly and delicious. Now picture that happening to the oceans, all day, every day, and the result is distinctly less effervescent: Dissolved CO2 turns into carbonic acid turns into dissolving shellfish, stressed-out fish, fewer clouds, plummeting biodiversity, collapsed ecosystems, total annihilation. I may be leaving out a few details with the seltzer metaphor, but it turns out I’m not the only one short on particulars. Dans un nouveau rapport, l'UNESCO prévient que l'acidification des océans s'effectue à un rythme sans précédent.

'Super corals' offer hope as oceans turn acidic. Corals began building reefs at least 200 million years ago, predating humans by at least 199.8 million years. » 1356 Climat (21) : Conséquences (3) – Les Océans. What is Ocean Acidification? What is ocean acidification? Un Equilibre chimique menacé ou l'acidification des océans. Changes in Sea Saltiness Show We’re Affecting the Climate.

Endangered Oceans. Les océans n'ont jamais été aussi acides. Health of oceans 'declining fast' Fabien Cousteau pulls a Spongebob to live at the bottom of the sea for a month.

Acidification ET surpêche ne font pas bon ménage. – alwen