ScienceDaily (Jan. 17, 2012) — Geoscientists at the University of Massachusetts Amherst and the University of Minnesota this week published the first evidence that warm-cold climate oscillations well known in the Northern Hemisphere over the most recent glacial period also appear as tropical rainfall variations in the Amazon Basin of South America. It is the first clear expression of these cycles in the Southern Hemisphere.
The work by Stephen Burns and his doctoral student Lisa Kanner at UMass Amherst is reported in the current issue of Science. Burns says, “The study also demonstrates that rainfall in the Southern Hemisphere of South America is, though to a lesser extent, also influenced by temperature changes in the Antarctic, which has not been previously observed.”
The last glacial period, from about 10,000 to about 120,000 years ago, saw North America and Western Europe covered in a thick continental ice sheet, the geoscientist points out. Yet climate was also highly unstable during the period, cycling every few thousand years between warm and cold, dry periods in the high northern latitudes. Temperatures could change by as much as 10 to 15 degrees Celsius. Read Article