Climate and groundwater recharge during the last glaciation in an ice-covered region
A multitracer study of a small aquifer in northern Switzerland indicates that the atmosphere in central Europe cooled by at least 5 degreesC during the last glacial period. The relation between oxygen isotope ratios (delta18O) and recharge temperatures reconstructed for this period is similar to the present-day one if a shift in the delta18O value of the oceans during the ice age is taken into account. This similarity suggests that the present-day delta18O-temperature relation can be used to reconstruct paleoclimate conditions in northern Switzerland. A gap in calculated groundwater age between about 17,000 and 25,000 years before the present indicates that during the last glacial maximum, local groundwater recharge was prevented by overlying glaciers.
U. Beyerle, W. Aeschbach-Hertig, D. M. Imboden, R. Kipfer, Department of Environmental Physics, Swiss Federal Institute of Technology (ETH) Zurich and Swiss Federal Institute of Environmental Science and Technology (EAWAG), 8600 Dubendor.
U
Beyerle
R
Purtschert
W
Aeschbach-Hertig
DM
Imboden
HH
Loosli
R
Wieler
R
Kipfer