Cd. Charles et al., GLACIAL-INTERGLACIAL CHANGES IN MOISTURE SOURCES FOR GREENLAND - INFLUENCES ON THE ICE CORE RECORD OF CLIMATE, Science, 263(5146), 1994, pp. 508-511
Large, abrupt shifts in the O-18/O-16 ratio found in Greenland ice mus
t reflect real features of the climate system variability. These isoto
pic shifts can be viewed as a result of air temperature fluctuations,
but determination of the cause of the changes-the most crucial issue f
or future climate concerns-requires a detailed understanding of the co
ntrols on isotopes in precipitation. Results from general circulation
model experiments suggest that the sources of Greenland precipitation
varied with different climate states, allowing dynamic atmospheric mec
hanisms for influencing the ice core isotope shifts.