The cooling of the Pacific Ocean between 11,000 and 10,000 years ago (the so-called Younger Dryas event), which has been indicated by paleovegetation studies in Alaska and Japan, has now been confirmed by radiocarbon-dated oxygen isotope studies of cores from the deep waters of the Sulu Sea, near the Philippines. This demonstrates clearly that the cooling event was not confined to the North Atlantic, as was once supposed, but was a major global shift in climate. The cause of the reversal of the general warming trend is still in doubt, but lower atmospheric carbon dioxide may have contributed to its occurrence.

H.R. Kudrass, H. Erlenkeuser, R. Vollbrecht, W. Weiss, "Global nature of the Younger Dryas cooling event inferred from oxygen isotope data from Sulu Sea cores," Nature, 349, 406-8, 31 January 1991. (Bundesandtalt fur Geowissenschaften, Hannover; Institut fur Reine un Angewandte Kernphysik, Kiel; et al.)

Plants that trap insects and...

Interested in reading more?

Become a Member of

Receive full access to digital editions of The Scientist, as well as TS Digest, feature stories, more than 35 years of archives, and much more!
Already a member?