Hemispheric Asynchrony of Abrupt Climate Change

During the past 80,000 years there have been rapid climate swings that occurred synchronously throughout the Northern Hemisphere. However, there has been intense debate over whether these changes were global, occurring at the same time in the Southern Hemisphere. In her Perspective, [Lynch-Stieglitz][1] comments on new work ([ Lamy et al. ][2]) that supports the well-developed paradigm of asynchronous changes in the Northern and Southern Hemispheres and suggests why most land-based records appear to support hemispheric synchrony. [1]: http://www.sciencemag.org/cgi/content/full/304/5679/1919 [2]: http://www.sciencemag.org/cgi/content/short/304/5679/1959