Continental drift is capable of suffocating marine oxygen.
A previously overlooked factor—the position of the continents—helps fill Earth’s oceans with life-supporting oxygen. Continental drift could ultimately have the opposite effect, killing off the majority of deep-ocean creatures. “Continental drift seems so slow, as if nothing drastic could come of it, but when the ocean is full, even a seemingly tiny event could cause the widespread death of marine life,” said Andy Ridgwell, geologist at the University of California, Riverside. Ridgwell is a co-author of a new study on the forces affecting ocean oxygen. As surface ocean water approaches the north or south pole, it becomes colder and denser and then sinks. When water sinks, it carries oxygen drawn from the Earth’s atmosphere to the ocean floor. Fish on a deep reef at Pearl and Hermes Atoll in Papahānaumokuākea Marine Monument near Hawaii. Credit: Greg McFall, NOAA Eventually, a return flow brings the nutrients released from the submerged organic matter back to the surface of the ocean, where it fuels plankton growth. Today’s oceans contain an incredible variety of fish and other animals supported both by the continuous supply of oxygen at lower depths and by organic matter produced at the surface. New research has discovered that this circulation of oxygen and nutrients can end quite suddenly. Using complex computer models, the scientists investigated whether the positions of the continental plates affect how the ocean moves oxygen around it. They were surprised to find that he does. This finding, led by researchers at UC Riverside, is detailed in the journal Nature. Published today (August 17, 2022). Puffer fish resting near the Florida Keys. Credit: OAR/National Undersea Research Program (NURP). University of Maine “Many millions of years ago, not long after animal life began in the ocean, the entire global ocean circulation seemed to stop periodically,” Ridgwell said. “We didn’t expect to find that the movement of the continents could cause the sinking of surface water and oxygen to stop and potentially dramatically affect the way life evolved on Earth.” Until now, the models used to investigate the evolution of marine oxygen over the past 540 million years were relatively simple and did not take ocean circulation into account. In these models, ocean anoxia—times when ocean oxygen disappeared—indicates a drop in atmospheric oxygen concentrations. “Scientists previously assumed that changing oxygen levels in the ocean mostly reflected similar fluctuations in the atmosphere,” said Alexandre Pohl, first author of the study and former UCR paleoclimate modeler, now at Université Bourgogne Franche-Comté in France. Diorama of ancient marine life of the Ediacaran period on display at the Smithsonian Institution. Credit: Smithsonian For the first time, this study used a model in which the ocean is represented in three dimensions and in which ocean currents are calculated. According to the results, the collapse of the global water circulation leads to a sharp separation between the oxygen levels at the upper and lower depths. This separation meant that the entire sea floor, except for shallow parts near the coast, was completely deprived of oxygen for many tens of millions of years, until about 440 million years ago at the beginning of the Silurian period. “A collapse of circulation would be a death sentence for anything that couldn’t swim closer to the surface and the life-giving oxygen still in the atmosphere,” Ridgwell said. Creatures of the deep include strange-looking fish, giant worms and crustaceans, squid, sponges and more. The paper does not address whether or when Earth might expect a similar event in the future. In reality, it is difficult to determine when a meltdown might occur or what triggers it. However, existing climate models confirm that increasing global warming will weaken ocean circulation, and some models even predict an eventual collapse of the circulation sector starting in the North Atlantic. “We would need a higher-resolution climate model to predict a mass extinction event,” Ridgwell said. “We already have concerns about the circulation of water in the North Atlantic today, and there are indications that the flow of water to depth is decreasing.” In theory, an unusually hot summer or the erosion of a cliff could trigger a cascade of processes that upend life as seen today, Ridgwell said. “You would think that the surface of the ocean, the part where you can surf or sail, is where all the action is. But underneath, the ocean works tirelessly, providing vital oxygen to animals in the murky depths,” Ridgwell said. “The ocean allows life to flourish, but it can take that life away again. Nothing rules it out as the continental plates continue to move.” Citation: “Continental shaping controls ocean oxygenation during the Phanerozoic” by Alexandre Pohl, Andy Ridgwell, Richard G. Stockey, Christophe Thomazo, Andrew Keane, Emmanuelle Vennin, and Christopher R. Scotese, 17 Aug 2022, Nature. 11038/103801. 022-05018-z
title: “The Sleeping Giant Could End Life In The Ocean Klmat” ShowToc: true date: “2022-11-05” author: “Larry Brooks”
Continental drift is capable of suffocating marine oxygen.
A previously overlooked factor—the position of the continents—helps fill Earth’s oceans with life-supporting oxygen. Continental drift could ultimately have the opposite effect, killing off the majority of deep-ocean creatures. “Continental drift seems so slow, as if nothing drastic could come of it, but when the ocean is full, even a seemingly tiny event could cause the widespread death of marine life,” said Andy Ridgwell, geologist at the University of California, Riverside. Ridgwell is a co-author of a new study on the forces affecting ocean oxygen. As surface ocean water approaches the north or south pole, it becomes colder and denser and then sinks. When water sinks, it carries oxygen drawn from the Earth’s atmosphere to the ocean floor. Fish on a deep reef at Pearl and Hermes Atoll in Papahānaumokuākea Marine Monument near Hawaii. Credit: Greg McFall, NOAA Eventually, a return flow brings the nutrients released from the submerged organic matter back to the surface of the ocean, where it fuels plankton growth. Today’s oceans contain an incredible variety of fish and other animals supported both by the continuous supply of oxygen at lower depths and by organic matter produced at the surface. New research has discovered that this circulation of oxygen and nutrients can end quite suddenly. Using complex computer models, the scientists investigated whether the positions of the continental plates affect how the ocean moves oxygen around it. They were surprised to find that he does. This finding, led by researchers at UC Riverside, is detailed in the journal Nature. Published today (August 17, 2022). Puffer fish resting near the Florida Keys. Credit: OAR/National Undersea Research Program (NURP). University of Maine “Many millions of years ago, not long after animal life began in the ocean, the entire global ocean circulation seemed to stop periodically,” Ridgwell said. “We didn’t expect to find that the movement of the continents could cause the sinking of surface water and oxygen to stop and potentially dramatically affect the way life evolved on Earth.” Until now, the models used to investigate the evolution of marine oxygen over the past 540 million years were relatively simple and did not take ocean circulation into account. In these models, ocean anoxia—times when ocean oxygen disappeared—indicates a drop in atmospheric oxygen concentrations. “Scientists previously assumed that changing oxygen levels in the ocean mostly reflected similar fluctuations in the atmosphere,” said Alexandre Pohl, first author of the study and former UCR paleoclimate modeler, now at Université Bourgogne Franche-Comté in France. Diorama of ancient marine life of the Ediacaran period on display at the Smithsonian Institution. Credit: Smithsonian For the first time, this study used a model in which the ocean is represented in three dimensions and in which ocean currents are calculated. According to the results, the collapse of the global water circulation leads to a sharp separation between the oxygen levels at the upper and lower depths. This separation meant that the entire sea floor, except for shallow parts near the coast, was completely deprived of oxygen for many tens of millions of years, until about 440 million years ago at the beginning of the Silurian period. “A collapse of circulation would be a death sentence for anything that couldn’t swim closer to the surface and the life-giving oxygen still in the atmosphere,” Ridgwell said. Creatures of the deep include strange-looking fish, giant worms and crustaceans, squid, sponges and more. The paper does not address whether or when Earth might expect a similar event in the future. In reality, it is difficult to determine when a meltdown might occur or what triggers it. However, existing climate models confirm that increasing global warming will weaken ocean circulation, and some models even predict an eventual collapse of the circulation sector starting in the North Atlantic. “We would need a higher-resolution climate model to predict a mass extinction event,” Ridgwell said. “We already have concerns about the circulation of water in the North Atlantic today, and there are indications that the flow of water to depth is decreasing.” In theory, an unusually hot summer or the erosion of a cliff could trigger a cascade of processes that upend life as seen today, Ridgwell said. “You would think that the surface of the ocean, the part where you can surf or sail, is where all the action is. But underneath, the ocean works tirelessly, providing vital oxygen to animals in the murky depths,” Ridgwell said. “The ocean allows life to flourish, but it can take that life away again. Nothing rules it out as the continental plates continue to move.” Citation: “Continental shaping controls ocean oxygenation during the Phanerozoic” by Alexandre Pohl, Andy Ridgwell, Richard G. Stockey, Christophe Thomazo, Andrew Keane, Emmanuelle Vennin, and Christopher R. Scotese, 17 Aug 2022, Nature. 11038/103801. 022-05018-z
title: “The Sleeping Giant Could End Life In The Ocean Klmat” ShowToc: true date: “2022-12-10” author: “Stephanie Aguilera”
Continental drift is capable of suffocating marine oxygen.
A previously overlooked factor—the position of the continents—helps fill Earth’s oceans with life-supporting oxygen. Continental drift could ultimately have the opposite effect, killing off the majority of deep-ocean creatures. “Continental drift seems so slow, as if nothing drastic could come of it, but when the ocean is full, even a seemingly tiny event could cause the widespread death of marine life,” said Andy Ridgwell, geologist at the University of California, Riverside. Ridgwell is a co-author of a new study on the forces affecting ocean oxygen. As surface ocean water approaches the north or south pole, it becomes colder and denser and then sinks. When water sinks, it carries oxygen drawn from the Earth’s atmosphere to the ocean floor. Fish on a deep reef at Pearl and Hermes Atoll in Papahānaumokuākea Marine Monument near Hawaii. Credit: Greg McFall, NOAA Eventually, a return flow brings the nutrients released from the submerged organic matter back to the surface of the ocean, where it fuels plankton growth. Today’s oceans contain an incredible variety of fish and other animals supported both by the continuous supply of oxygen at lower depths and by organic matter produced at the surface. New research has discovered that this circulation of oxygen and nutrients can end quite suddenly. Using complex computer models, the scientists investigated whether the positions of the continental plates affect how the ocean moves oxygen around it. They were surprised to find that he does. This finding, led by researchers at UC Riverside, is detailed in the journal Nature. Published today (August 17, 2022). Puffer fish resting near the Florida Keys. Credit: OAR/National Undersea Research Program (NURP). University of Maine “Many millions of years ago, not long after animal life began in the ocean, the entire global ocean circulation seemed to stop periodically,” Ridgwell said. “We didn’t expect to find that the movement of the continents could cause the sinking of surface water and oxygen to stop and potentially dramatically affect the way life evolved on Earth.” Until now, the models used to investigate the evolution of marine oxygen over the past 540 million years were relatively simple and did not take ocean circulation into account. In these models, ocean anoxia—times when ocean oxygen disappeared—indicates a drop in atmospheric oxygen concentrations. “Scientists previously assumed that changing oxygen levels in the ocean mostly reflected similar fluctuations in the atmosphere,” said Alexandre Pohl, first author of the study and former UCR paleoclimate modeler, now at Université Bourgogne Franche-Comté in France. Diorama of ancient marine life of the Ediacaran period on display at the Smithsonian Institution. Credit: Smithsonian For the first time, this study used a model in which the ocean is represented in three dimensions and in which ocean currents are calculated. According to the results, the collapse of the global water circulation leads to a sharp separation between the oxygen levels at the upper and lower depths. This separation meant that the entire sea floor, except for shallow parts near the coast, was completely deprived of oxygen for many tens of millions of years, until about 440 million years ago at the beginning of the Silurian period. “A collapse of circulation would be a death sentence for anything that couldn’t swim closer to the surface and the life-giving oxygen still in the atmosphere,” Ridgwell said. Creatures of the deep include strange-looking fish, giant worms and crustaceans, squid, sponges and more. The paper does not address whether or when Earth might expect a similar event in the future. In reality, it is difficult to determine when a meltdown might occur or what triggers it. However, existing climate models confirm that increasing global warming will weaken ocean circulation, and some models even predict an eventual collapse of the circulation sector starting in the North Atlantic. “We would need a higher-resolution climate model to predict a mass extinction event,” Ridgwell said. “We already have concerns about the circulation of water in the North Atlantic today, and there are indications that the flow of water to depth is decreasing.” In theory, an unusually hot summer or the erosion of a cliff could trigger a cascade of processes that upend life as seen today, Ridgwell said. “You would think that the surface of the ocean, the part where you can surf or sail, is where all the action is. But underneath, the ocean works tirelessly, providing vital oxygen to animals in the murky depths,” Ridgwell said. “The ocean allows life to flourish, but it can take that life away again. Nothing rules it out as the continental plates continue to move.” Citation: “Continental shaping controls ocean oxygenation during the Phanerozoic” by Alexandre Pohl, Andy Ridgwell, Richard G. Stockey, Christophe Thomazo, Andrew Keane, Emmanuelle Vennin, and Christopher R. Scotese, 17 Aug 2022, Nature. 11038/103801. 022-05018-z
title: “The Sleeping Giant Could End Life In The Ocean Klmat” ShowToc: true date: “2022-10-22” author: “Jane Morgan”
Continental drift is capable of suffocating marine oxygen.
A previously overlooked factor—the position of the continents—helps fill Earth’s oceans with life-supporting oxygen. Continental drift could ultimately have the opposite effect, killing off the majority of deep-ocean creatures. “Continental drift seems so slow, as if nothing drastic could come of it, but when the ocean is full, even a seemingly tiny event could cause the widespread death of marine life,” said Andy Ridgwell, geologist at the University of California, Riverside. Ridgwell is a co-author of a new study on the forces affecting ocean oxygen. As surface ocean water approaches the north or south pole, it becomes colder and denser and then sinks. When water sinks, it carries oxygen drawn from the Earth’s atmosphere to the ocean floor. Fish on a deep reef at Pearl and Hermes Atoll in Papahānaumokuākea Marine Monument near Hawaii. Credit: Greg McFall, NOAA Eventually, a return flow brings the nutrients released from the submerged organic matter back to the surface of the ocean, where it fuels plankton growth. Today’s oceans contain an incredible variety of fish and other animals supported both by the continuous supply of oxygen at lower depths and by organic matter produced at the surface. New research has discovered that this circulation of oxygen and nutrients can end quite suddenly. Using complex computer models, the scientists investigated whether the positions of the continental plates affect how the ocean moves oxygen around it. They were surprised to find that he does. This finding, led by researchers at UC Riverside, is detailed in the journal Nature. Published today (August 17, 2022). Puffer fish resting near the Florida Keys. Credit: OAR/National Undersea Research Program (NURP). University of Maine “Many millions of years ago, not long after animal life began in the ocean, the entire global ocean circulation seemed to stop periodically,” Ridgwell said. “We didn’t expect to find that the movement of the continents could cause the sinking of surface water and oxygen to stop and potentially dramatically affect the way life evolved on Earth.” Until now, the models used to investigate the evolution of marine oxygen over the past 540 million years were relatively simple and did not take ocean circulation into account. In these models, ocean anoxia—times when ocean oxygen disappeared—indicates a drop in atmospheric oxygen concentrations. “Scientists previously assumed that changing oxygen levels in the ocean mostly reflected similar fluctuations in the atmosphere,” said Alexandre Pohl, first author of the study and former UCR paleoclimate modeler, now at Université Bourgogne Franche-Comté in France. Diorama of ancient marine life of the Ediacaran period on display at the Smithsonian Institution. Credit: Smithsonian For the first time, this study used a model in which the ocean is represented in three dimensions and in which ocean currents are calculated. According to the results, the collapse of the global water circulation leads to a sharp separation between the oxygen levels at the upper and lower depths. This separation meant that the entire sea floor, except for shallow parts near the coast, was completely deprived of oxygen for many tens of millions of years, until about 440 million years ago at the beginning of the Silurian period. “A collapse of circulation would be a death sentence for anything that couldn’t swim closer to the surface and the life-giving oxygen still in the atmosphere,” Ridgwell said. Creatures of the deep include strange-looking fish, giant worms and crustaceans, squid, sponges and more. The paper does not address whether or when Earth might expect a similar event in the future. In reality, it is difficult to determine when a meltdown might occur or what triggers it. However, existing climate models confirm that increasing global warming will weaken ocean circulation, and some models even predict an eventual collapse of the circulation sector starting in the North Atlantic. “We would need a higher-resolution climate model to predict a mass extinction event,” Ridgwell said. “We already have concerns about the circulation of water in the North Atlantic today, and there are indications that the flow of water to depth is decreasing.” In theory, an unusually hot summer or the erosion of a cliff could trigger a cascade of processes that upend life as seen today, Ridgwell said. “You would think that the surface of the ocean, the part where you can surf or sail, is where all the action is. But underneath, the ocean works tirelessly, providing vital oxygen to animals in the murky depths,” Ridgwell said. “The ocean allows life to flourish, but it can take that life away again. Nothing rules it out as the continental plates continue to move.” Citation: “Continental shaping controls ocean oxygenation during the Phanerozoic” by Alexandre Pohl, Andy Ridgwell, Richard G. Stockey, Christophe Thomazo, Andrew Keane, Emmanuelle Vennin, and Christopher R. Scotese, 17 Aug 2022, Nature. 11038/103801. 022-05018-z
title: “The Sleeping Giant Could End Life In The Ocean Klmat” ShowToc: true date: “2022-11-03” author: “Lisa Ford”
Continental drift is capable of suffocating marine oxygen.
A previously overlooked factor—the position of the continents—helps fill Earth’s oceans with life-supporting oxygen. Continental drift could ultimately have the opposite effect, killing off the majority of deep-ocean creatures. “Continental drift seems so slow, as if nothing drastic could come of it, but when the ocean is full, even a seemingly tiny event could cause the widespread death of marine life,” said Andy Ridgwell, geologist at the University of California, Riverside. Ridgwell is a co-author of a new study on the forces affecting ocean oxygen. As surface ocean water approaches the north or south pole, it becomes colder and denser and then sinks. When water sinks, it carries oxygen drawn from the Earth’s atmosphere to the ocean floor. Fish on a deep reef at Pearl and Hermes Atoll in Papahānaumokuākea Marine Monument near Hawaii. Credit: Greg McFall, NOAA Eventually, a return flow brings the nutrients released from the submerged organic matter back to the surface of the ocean, where it fuels plankton growth. Today’s oceans contain an incredible variety of fish and other animals supported both by the continuous supply of oxygen at lower depths and by organic matter produced at the surface. New research has discovered that this circulation of oxygen and nutrients can end quite suddenly. Using complex computer models, the scientists investigated whether the positions of the continental plates affect how the ocean moves oxygen around it. They were surprised to find that he does. This finding, led by researchers at UC Riverside, is detailed in the journal Nature. Published today (August 17, 2022). Puffer fish resting near the Florida Keys. Credit: OAR/National Undersea Research Program (NURP). University of Maine “Many millions of years ago, not long after animal life began in the ocean, the entire global ocean circulation seemed to stop periodically,” Ridgwell said. “We didn’t expect to find that the movement of the continents could cause the sinking of surface water and oxygen to stop and potentially dramatically affect the way life evolved on Earth.” Until now, the models used to investigate the evolution of marine oxygen over the past 540 million years were relatively simple and did not take ocean circulation into account. In these models, ocean anoxia—times when ocean oxygen disappeared—indicates a drop in atmospheric oxygen concentrations. “Scientists previously assumed that changing oxygen levels in the ocean mostly reflected similar fluctuations in the atmosphere,” said Alexandre Pohl, first author of the study and former UCR paleoclimate modeler, now at Université Bourgogne Franche-Comté in France. Diorama of ancient marine life of the Ediacaran period on display at the Smithsonian Institution. Credit: Smithsonian For the first time, this study used a model in which the ocean is represented in three dimensions and in which ocean currents are calculated. According to the results, the collapse of the global water circulation leads to a sharp separation between the oxygen levels at the upper and lower depths. This separation meant that the entire sea floor, except for shallow parts near the coast, was completely deprived of oxygen for many tens of millions of years, until about 440 million years ago at the beginning of the Silurian period. “A collapse of circulation would be a death sentence for anything that couldn’t swim closer to the surface and the life-giving oxygen still in the atmosphere,” Ridgwell said. Creatures of the deep include strange-looking fish, giant worms and crustaceans, squid, sponges and more. The paper does not address whether or when Earth might expect a similar event in the future. In reality, it is difficult to determine when a meltdown might occur or what triggers it. However, existing climate models confirm that increasing global warming will weaken ocean circulation, and some models even predict an eventual collapse of the circulation sector starting in the North Atlantic. “We would need a higher-resolution climate model to predict a mass extinction event,” Ridgwell said. “We already have concerns about the circulation of water in the North Atlantic today, and there are indications that the flow of water to depth is decreasing.” In theory, an unusually hot summer or the erosion of a cliff could trigger a cascade of processes that upend life as seen today, Ridgwell said. “You would think that the surface of the ocean, the part where you can surf or sail, is where all the action is. But underneath, the ocean works tirelessly, providing vital oxygen to animals in the murky depths,” Ridgwell said. “The ocean allows life to flourish, but it can take that life away again. Nothing rules it out as the continental plates continue to move.” Citation: “Continental shaping controls ocean oxygenation during the Phanerozoic” by Alexandre Pohl, Andy Ridgwell, Richard G. Stockey, Christophe Thomazo, Andrew Keane, Emmanuelle Vennin, and Christopher R. Scotese, 17 Aug 2022, Nature. 11038/103801. 022-05018-z
