Canadian Press: New research suggests that longer autumns resulting from climate change may be diminishing the role northern forests can play in the fight against global warming. Soil microbes warmed by the summer and fed by falling leaves emit more carbon than the trees absorb through photosynthesis, said Hank Margolis, one of the authors of the paper published Wednesday in the respected journal Nature. "Our thinking is that the microbes gain more from the autumn warming than the tree …