We may have no one but ourselves—in part—to blame for the heavy rains and floods that have been plaguing everywhere from Nashville to Australia in recent years. Prior studies discovered that the likelihood of experiencing severe precipitation on a given day jumped 7% over the years 1951 to 1999, and a new study, based on elaborate computer modeling, has found that the increase cannot be attributed to natural variability. The computers found that the bump only made sense when mankind's effects on the atmosphere, by way of activities like the burning of fossil fuels, were factored in.
A second study, also published in Nature, looked at major flooding in England and Wales during 2000. Using more computer simulations, researchers compared the events of that year to a hypothetical year that existed in a world that saw no Industrial Revolution and the release of few greenhouse gases. The result? The gases basically doubled the chances of those floods occurring. The New York Times notes that the studies are unlikely to change the minds of climate-change contrarians, who feel computer simulations can't capture the full complexity of the real world. (More extreme weather stories.)