Duluth News Tribune: Substantial areas of what is now Northland forest may someday change to savanna or grassland, according to University of Minnesota scientists detailing the impacts of climate change in a newly published research paper. The paper predicts Duluth-area forest types — red and white pine, birch and aspen — will recede northeast to about Thunder Bay, while prairie-like habitats now common in southern and central Minnesota will move into the North-land. The scientific paper, …