Climate and vegetation history of the midcontinent from 75 to 25 ka: A speleothem record from Crevice Cave, Missouri, USA

Four Missouri stalagmites yield consistent overlapping records of oxygen an d carbon isotopic changes and provide a climate and vegetation history with submillennial resolution from 75 to 25 thousand years ago (ka). The thoriu m-230-dated records reveal that between 75 and 55 ka, the midcontinental cl imate oscillated on millennial time scales between cold and warm, and veget ation alternated among forest, savanna, and prairie. Temperatures were high est and prairie vegetation peaked between 59 and 55 ka. Climate cooled and forest replaced grassland at 55 ka, when global ice sheets began to build d uring the early part of Marine Oxygen Isotope Stage 3.