Global Warming --- Impact --- Causes War

Global Warming Impact --- Warming = Brink

Another says that the effects are already rippling through the food web in Antarctica. And a third says humans, and their ever-increasing carbon emissions, are acidifying the ocean in a "grand planetary experiment" that could have devastating impacts. Marine scientists Ove Hoegh-Guldberg, at the University of Queensland in Australia, and John Bruno, at the University of North Carolina, describe how the oceans act as a "heat sink" and are slowly heating up along with the atmosphere as greenhouse gas emissions climb. The warming, they say, is "likely to have profound influences on the strength, direction and behaviour" of major ocean currents and far-reaching impacts on sea life. The oceans also soak up close to a third of the carbon dioxide that humans put into the atmosphere, and it reacts with sea water to form acidic ions. The rising acidity "represents a major departure from the geochemical conditions that have prevailed in the global ocean for hundreds of thousands, if not millions of years," the scientists report. Add it all up and they say there is there is "overwhelming" evidence human activities are driving changes on a scale similar to volcanic eruptions or meteorite strikes, which have driven ecosystems to collapse in the past. "The impacts of anthropogenic (human) climate change so far include decreased ocean productivity, altered food web dynamics, reduced abundance of habitat-forming species, shifting species distributions and a greater incidence of disease," they say. In a second report, Oscar Schofield at Rutgers University and his colleagues describe how rising temperatures over the last 30 years have coincided with a shift in the food web along the West Antarctic Peninsula -most notably to a shrinking of marine algae cells. Organisms known as tunicates are so efficient at feeding on the smaller algae they appear to be displacing krill, a mainstay of many creatures up the food web. Fish, seals, whales, penguins and other seabirds could all be affected, they say. A news report accompanying the Science papers on the oceans says by increasing the ocean's acidity, "humans are caught up in a grand planetary experiment" that could take a "potentially devastating toll on marine life." The rising acidity could erode the calcium carbonate shells and skeletons of corals, mollusks and some algae and plankton -and there is evidence it is already starting to occur. "The physics and chemistry of adding an acid to the ocean are so well understood, so inexorable, that there cannot be an iota of doubt -gigatons of acid are lowering the pHof theworldocean, humans are totally responsible, and the more carbon dioxide we emit, the worse it's going to get," it says.

It goes on to quote a recent issue of the journal Oceanography that said unconstrained growth of emissions is likely to leave the current era of human planetary dominance "as one of the most notable, if not cataclysmic, events in the history of our planet."