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"USC researcher experiments with changing ocean chemistry Jan. 19, 2011 | Molly Peterson | KPCC In his lab, USC's Dave Hutchins is simulating possible future atmospheres and temperatures for the Earth. He says he's trying to figure out how tiny organisms that form the base of the food web will react to a more carbon-intense ocean. Burning fossil fuels doesn't just put more carbon into the atmosphere and help warm the climate. It's also changing the chemistry of sea water. KPCC's Molly Peterson visits a University of Southern California researcher who studies the consequences of a more corrosive ocean. Tailpipes and refineries and smokestacks as far as the eye can see in Los Angeles symbolize the way people change the planet's climate. They remind Dave Hutchins that the ocean's changing too. Hutchins teaches marine biology at USC. He says about a third of all the carbon, or CO2, that people have pushed into earth's atmosphere ends up in sea water - "which is a good thing for us because if the ocean hadn't taken up that CO2 the greenhouse effect would be far more advanced than it is." He smiles. Hutchins says that carbon is probably not so good for the ocean. "The more carbon dioxide that enters the ocean the more acidic the ocean gets." On the pH scale, smaller numbers represent more acidity. The Monterey Bay Aquarium Research Institute estimates we've pumped 500 million tons of carbon into the world's oceans. Dave Hutchins at USC says that carbon has already lowered the pH value for sea water. "By the end of this century we are going to have increased the amount of acid in the ocean by maybe 200 percent over natural pre-industrial levels," he says. "So we are driving the chemistry of the ocean into new territory - into areas that it has never seen." Hutchins is one of dozens of scientists who study the ripples of that new chemistry into the marine ecosystem. Now for an aside. I make bubbly water at home with a soda machine, and to do that, I pump ca

NARRATOR: Even though the ocean covers seventy percent of the Earth's surface, people tend to know more information about land than the sea. As a result, our understanding of the ocean is often incomplete or full of misconceptions. How well do you know the ocean? You may think Earth has five separate oceans. They're clearly labeled on our maps. But, in actuality, these are all connected, and part of one global ocean system. Ever wonder why the ocean is blue? You may have heard its because the water reflects the color of the sky. Not quite. Sunlight contains all the colors of the rainbow. When it hits the ocean, it gets scattered by the water molecules. Blue light is scattered the most, which is why the ocean appears blue. Even more interesting is that floating plants and sediments in the water can cause light to bounce in such a way for the ocean to appear green, yellow, and even red! Another idea some people have is that the sea floor is flat. Actually, just like land, the sea floor has canyons, plains, and mountain ranges. And many of these features are even bigger than those found on land. You may also think that our ocean's saltwater is just a mix of water and table salt. Not so. Seawater's "salt" is actually made of dissolved minerals from surface runoff. That is, excess water from rain and melting snow flowing over land and into the sea. This is why the ocean doesn't have the same level of salinity everywhere. Salinity varies by location and season. Finally, you may have heard that melting sea ice will cause sea levels to rise. In reality, sea ice is just frozen seawater, and because it routinely freezes and melts, its volume is already accounted for in the ocean. Sea levels can rise, however, from ice that melts off land and into the ocean. Understanding basic facts about the ocean is important since it affects everything from our atmosphere to our ecosystems. By knowing your ocean, you are better prepared to help protect it.

"Science 25 November 2011: Vol. 334 no. 6059 p. 1040 DOI: 10.1126/science.334.6059.1040 * News & Analysis Climate Change Humans Are Driving Extreme Weather; Time to Prepare 1. Richard A. Kerr Figure View larger version: * In this page * In a new window Thai floods 2011 Hurricane Katrina 2005 Texas drought 2011 "CREDITS (LEFT TO RIGHT): PAULA BRONSTEIN/GETTY IMAGES; JEFF SCHMALTZ, MODIS RAPID RESPONSE TEAM, NASA/GSFC; NOAA" An international scientific assessment finds for the first time that human activity has indeed driven not just global warming but also increases in some extreme weather and climate events around the world in recent decades. And those and likely other weather extremes will worsen in coming decades as greenhouse gases mount, the report finds. But uncertainties are rife in the still-emerging field of extreme events. Scientists cannot attribute a particular drought or flood to global warming, and they can say little about past or future trends in the risk of high-profile hazards such as tropical cyclones. Damage from weather disasters has been climbing, but the report can attribute that trend only to the increasing exposure of life and property to weather risks. Climate change may be involved, but a case cannot yet be made. Despite the uncertainties, the special report from the Intergovernmental Panel on Climate Change (IPCC) released 18 November stresses that there is still reason for taking action now. The panel recommends "low-regrets measures," such as improvements in everything from drainage systems to early warning systems. Such measures would benefit society in dealing with the current climate as well as with almost any range of possible future climates. The report takes a cautious, consensus-based approach that draws on the published literature. Headlines and even some scientists may point to the current Texas drought or the 2003 European heat wave as the result of the strengthening greenhouse. But the report fin