Reuters: The financial crisis has slashed industrial output and trade but it will be months before there is an accurate picture of how much the downturn has curbed greenhouse gas emissions, two leading scientists said on Friday. Preliminary data from the U.S. National Oceanic and Atmospheric Administration (NOAA) shows carbon dioxide levels rose last year to a global average of 384.9 parts per million, an increase of 2.2 ppm over 2007. But since then, the financial crisis has deepened, …