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Also TryPapers
- Acidification of the Oceans: Fastest Change in 300 Million Years (Time.com)
"The researchers found only one moment in the past when the oceans seemed to be changing anywhere near as fast as they are today. That was the Paleocene-Eocene Thermal Maximum (PETM), which occurred some 56 million years ago. Back in the 1990s, scientists excavated a layer of mud off the seafloor near Antarctica that was traced back to that period. Over the course of 5,000 years during the PETM, carbon levels in the atmosphere doubled for reasons scientists still don’t know. That pushed global temperatures up by 6 C—one of the reasons why the era is called 'hothouse Earth,' while the pH of the oceans may have fallen by as much as 0.45 units, becoming significantly more acidic." 02-12
- Acidification of the Oceans: Fastest Change in 300 Million Years (Time.com)
"The researchers found only one moment in the past when the oceans seemed to be changing anywhere near as fast as they are today. That was the Paleocene-Eocene Thermal Maximum (PETM), which occurred some 56 million years ago. Back in the 1990s, scientists excavated a layer of mud off the seafloor near Antarctica that was traced back to that period. Over the course of 5,000 years during the PETM, carbon levels in the atmosphere doubled for reasons scientists still don’t know. That pushed global temperatures up by 6 C—one of the reasons why the era is called 'hothouse Earth,' while the pH of the oceans may have fallen by as much as 0.45 units, becoming significantly more acidic." 02-12
- Acidification: The Destructive Force of CO2 on Oceans (Seattle Times)
"In this volcanic region, pure CO2 escapes naturally through cracks in the ocean floor. The gas bubbles alter the water’s chemistry the same way rising CO2 from cars and power plants is quickly changing the marine world."
"In fact, the water chemistry here is exactly what scientists predict most of the seas will be like in 60 to 80 years."
"That makes this isolated splash of coral reef a chilling vision of our future oceans." 12-14
- Are We Destroying the Oceans? (Time.com)
"But human-related injury to the oceans is rife. We have fished out an estimated 90% of the major commercial fish species that swim the high seas, including the giant and endangered blue fin tuna. The trawlers carrying out that destruction are raking the ocean floor, turning parts of the once vibrant continental shelf into so much mud. Climate change is warming the oceans, disrupting the fundamental structure of the marine food pyramid and destroying coral reefs. Meanwhile, increased concentrations of CO2 in the atmosphere are making the seas acidic, which threatens to kill off species in large numbers. 'The ocean is becoming a desert,' says Jeremy Jackson, the director of the Center for Marine Biodiversity and Conservation at the Scripps Institution of Oceanography."
"Pollution that has washed off the land — from sewage that contains chemical toxins to nitrate fertilizer from farmland — has infected the oceans, destroying once vibrant coastal waters. But it's a problem we barely notice, since for many of us the oceans are distant and out of sight." 04-10
- Experts Warn: Oceans Becoming Too Acidic (MSNBC News)
"The world's oceans are becoming more acidic, which poses a threat to sea life and Earth's fragile food chain, German researchers told delegates at a U.N. conference on climate change." 11-06
- Food Chain in Oceans Threatened (Time.com)
"Rising carbon dioxide in the atmosphere is threatening to make oceans too corrosive for marine organisms to grow protective shells, according to researchers."
"If emissions continue unabated, the entire Southern Ocean, which stretches north from the Antarctic coastline, and subarctic regions of the Pacific Ocean will soon become so acidic that the shells of marine creatures will soften and dissolve making them easy targets for predators. Others will not be able to grow sufficient shells to survive."
"The loss of shelled creatures at the lower end of the food chain could have disastrous consequences for larger marine animals." 9-05
- Ocean Acidification: The Other CO2 Problem (NOAA.gov)
"Fundamental changes in seawater chemistry are occurring throughout the world's oceans. Since the beginning of the industrial revolution, the release of carbon dioxide (CO2) from humankind's industrial and agricultural activities has increased the amount of CO2 in the atmosphere. The ocean absorbs about a quarter of the CO2 we release into the atmosphere every year, so as atmospheric CO2 levels increase, so do the levels in the ocean. Initially, many scientists focused on the benefits of the ocean removing this greenhouse gas from the atmosphere. However, decades of ocean observations now show that there is also a downside — the CO2 absorbed by the ocean is changing the chemistry of the seawater, a process called OCEAN ACIDIFICATION." 12-14
- Ocean Acidification: What Is It? (NOAA.gov)
"When carbon dioxide (CO2) is absorbed by seawater, chemical reactions occur that reduce seawater pH, carbonate ion concentration, and saturation states of biologically important calcium carbonate minerals."
"Since the beginning of the Industrial Revolution, the pH of surface ocean waters has fallen by 0.1 pH units. Since the pH scale, like the Richter scale, is logarithmic, this change represents approximately a 30 percent increase in acidity. Future predictions indicate that the oceans will continue to absorb carbon dioxide and become even more acidic. Estimates of future carbon dioxide levels, based on business as usual emission scenarios, indicate that by the end of this century the surface waters of the ocean could be nearly 150 percent more acidic, resulting in a pH that the oceans haven’t experienced for more than 20 million years." 12-14
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