Radiocarbon ages determined by the AMS method on hand-picked foraminifera shells are reported. The results allow estimates of the ventilation rate of the deep Atlantic and Pacific Oceans during glacial time. They also extend our knowledge of the chronology of events associated with the transition from full glacial conditions ca 15,000 years ago to full interglacial conditions ca 8000 years ago. This and the previous lists (Broecker et al 1988c) contain all the results obtained as part of this program through the fall of 1989.

A 30,000-year paleotemperature record derived from noble gases dissolved in carbon-14-dated ground water indicates that the climate in lowland Brazil (Piaui Province, 7 degrees S, 41.5 degrees W; altitude, 400 meters) was 5.4 degrees +/- 0.6 degrees C cooler during the last glacial maximum than today. This result suggests a rather uniform cooling of the Americas between 40 degrees S and 40 degrees N. A 5.4 degrees C cooling of tropical South America is consistent with pollen records, snow line reconstructions, and strontium/calcium ratios and delta(18)O coral records but is inconsistent with the sea-surface temperature reconstruction of CLIMAP (Climate: Long-Range Investigation, Mapping and Prediction). On the basis of these results, it appears that the tropical Americas are characterized by a temperature sensitivity comparable to that found in higher latitudes.

Very small samples from the Shroud of Turin have been dated by accelerator mass spectrometry in laboratories at Arizona, Oxford and Zurich. As controls, three samples whose ages had been determined independently were also dated. The results provide conclusive evidence that the linen of the Shroud of Turin is mediaeval. © 1989 Nature Publishing Group.