TY JOUR TI Long-term solar activity variations as a stimulator of abrupt climate change KW solar activity variations KW abrupt climate change KW ice-rafting events. JO Russian Journal of Earth Sciences AU Raspopov, O.M. AU Dergachev, A.V. AU Kolstrom, T.. AU Kuzmin, A.V. AU Lopatin, E.V. AU Lisitsyna, O.V. PY 2007 IS PB Geophysical Center of the Russian Academy of Sciences