While we now know more than ever before about Heinrich events, there are still many questions to be answered: Why were these changes so abrupt? What drove them? Are they a reflection of
variations in glaciological regimes, or are they driven by global climatic changes? How might they have been related to changes elsewhere in the world?
These issues are important, for they provide a better knowledge of the past that may prove
essential in understanding the course of future changes in earth's climate system. Most important, perhaps, is the potential instability of the West Antarctic Ice Sheet. Some scientists fear that this enormous ice sheet is unstable and might
collapse, thus generating modern-day Heinrich events in the Southern Hemisphere. The consequences of such a collapse would be dire indeed: a rapid 1-5 m rise in global sea levels that flood heavily-populated low-lying areas across the globe.
the twenty-first century, perhaps more data, improved methodologies, and a new generation of scientists will put within our reach the knowledge we need to understand Heinrich events and other mysteries of the earth's climate system.
John T. Andrews
NOAA Paleoclimatology Program and INSTAAR, University of Colorado, Boulder