OIL & GAS

Climate scientists, with the aid of diving robots probing the world's warming seas, have found the heat exchange between Earth and space is seriously out of balance - what the researchers called a "smoking gun" discovery that validates forecasts of global warming. They said the findings confirm that supercomputer models of climate change are on target and that global temperatures will rise 1 degree Fahrenheit (0.6 degrees Celsius) this century, even if greenhouse gases are capped tomorrow. If carbon dioxide and other heat-trapping emissions instead continue to grow, as expected, things could spin "out of our control," especially as ocean levels rise from melting Greenland and Antarctic ice sheets, the NASA-led scientists said. The study, published Thursday in the journal Science, is the latest to report growing certainty about global-warming projections. A leading European climate scientist called it useful supporting evidence. More than 1,800 technology-packed floats, deployed in oceans worldwide beginning in 2000, are regularly diving as much as a mile (kilometer) undersea to take temperature and other readings. Their precise measurements are supplemented by better satellite gauging of ocean levels, which rise both from meltwater and as the sea warms and expands. Researchers led by NASA's James Hansen used the improved data to calculate the oceans' heat content and the global "energy imbalance." They found that for every square meter of surface area, the planet is absorbing almost one watt more of the sun's energy than it is radiating back to space as heat - a historically large imbalance. Such absorbed energy will steadily warm the atmosphere. The 0.85-watt figure corresponds well with the energy imbalance predicted by the researchers' modeling of climate change through a supercomputer, the report said. Supercomputing models, numerical simulations of climate change, factor in many influences on climate, including greenhouse emissions - carbon dioxide, methane and other gases. Such gases, produced by everything from automobiles to pig farms, trap heat as they accumulate in the atmosphere. Significantly, those emissions have increased at a rate consistent with the detected energy imbalance, the researchers said. "There can no longer be genuine doubt that human-made gases are the dominant cause of observed warming," said Hansen, director of NASA's Goddard Institute for Space Studies at Columbia University's Earth Institute. "This energy imbalance is the 'smoking gun' that we have been looking for." Fourteen other specialists from NASA, Columbia and the Department of Energy co-authored the study. Scientists have found other possible "smoking guns" on global warming in recent years, but Klaus Hasselmann, a leading German climatologist, praised the Hansen report for its innovative work on energy imbalance. "This is valuable additional supporting evidence" of manmade climate change, he told The Associated Press. In February, scientists at San Diego's Scripps Institution of Oceanography said their research - not yet published - also showed a close correlation between climate models and the observed temperatures of oceans, further defusing skeptics' past criticism of uncertainties in modeling. Average atmospheric temperatures rose about 1 degree Fahrenheit (0.6 degrees Celsius) in the 20th century, and the Intergovernmental Panel on Climate Change, a U.N.-organized network of scientists, says supercomputer modeling shows they will rise between 2.5 degrees and 10.4 degrees Fahrenheit (1.4 degrees and 5.8 degrees Celsius) by the year 2100, depending on how well emissions are controlled. The Science study said the excess energy stored in the oceans means a 1-degree Fahrenheit (0.6-degree Celsius) rise in atmospheric temperatures is already "in the pipeline." This agrees with findings of U.S. government climate modelers reported last month. Besides raising ocean levels, global warming is expected to intensify storms, spread disease to new areas, and shift climate zones hundreds of miles, possibly making farmlands drier and deserts wetter. This story was taken in part from a service of the Associated Press (AP).