It's almost time to put a moratorium on WorldChanging stories pointing to yet more research showing that global warming is happening and is caused by human activity. Opposition to the idea at this point is entirely political, not scientific, and while the added data points are undoubtedly useful to researchers, such stories tend to run together. Our focus now should be on doing something about the problem. That said, the latest "it's happening" story, coming from this week's 2005 meeting of the American Association for the Advancement of Science, is still worth noting -- because of its certainty, its depth and its provenance.
Scientists at Scripps Institution of Oceanography at UC San Diego, working with colleagues at Lawrence Livermore National Laboratory's Program for Climate Model Diagnosis and Intercomparison (PCMDI), have found "clear" and "compelling evidence" of human-forced global warming in the oceans. The Times of London has the an extensive write-up:
"The debate about whether there is a global warming signal now is over, at least for rational people," said Tim Barnett, of the Scripps Institution of Oceanography in La Jolla, California. "The models got it right. If a politician stands up and says the uncertainty is too great to believe these models, that is no longer tenable."In the study, Dr Barnett’s team examined more than seven million observations of temperature, salinity and other variables in the world’s oceans, collected by the US National Oceanic and Atmospheric Administration, and compared the patterns with those that are predicted by computer models of various potential causes of climate change.
It found that natural variation in the Earth’s climate, or changes in solar activity or volcanic eruptions, which have been suggested as alternative explanations for rising temperatures, could not explain the data collected in the real world. Models based on man-made emissions of greenhouse gases, however, matched the observations almost precisely.
Emphasis mine. It's worth noting that Lawrence Livermore National Lab is best known for its work on nuclear weapon design and testing, along with early ballistic missile defense research; I have visited the labs several times, and spoken at length with some of the physicists there -- it is most definitely not a hotbed of liberal/green activism. Most of the LLNL folks I've met are scientists with a profound interest in understanding the world, and an active disdain for politics.
The BBC, CNN and others provide more details; unlike other global warming stories, this one seems to be getting wide play. Nature's blogger at the AAAS conference adds this:
Barnett certainly pulled out all the stops, as illustrated by his most eye-opening factoid. If global warming really has heated up the oceans as much as he calculates, then the total amount of extra energy dumped into the drink by mankind would power the state of California for 200,000 years.
Hyperbole, maybe, but pretty vivid.
