Fig. 15.4 Comparison of the d
18
O record of Lake Ammersee for the
last two centuries derived from the d
18
O of juvenil Candona
(d
18
O L (from C.sp), crosses) compared to the d
18
O L as predicted by a
two-box isotope hydrology model (d
18
O L (model), open circles), if the
lake was supplied with an inflow of river water with an isotopic
composition (d
18
O I (model), diamonds), controlled by the mean annual
air temperature (MAAT) (using d
18
O P = 0.58‰* MAAT—14.48‰ as
d
18
O P –MAAT relation). The upper graph shows the development over
time. The lower box compares the slope of the input relationship
(diamonds) with the slopes of the modelled (open circles) and the
ostracod-derived d
18
O L -MAAT relation. Air-temperature variations
dominate both the modelled and observed lake responses. The slopes of
the relationship of both the modelled and observed lake response to air
temperatures are decreased compared to the d
18
O P —temperature
relation, due to the incomplete reaction of d
18
O L to the fast climate
changes (von Grafenstein et al. 1996)
15 Air-Interface: d
18 O Records of Past Meteoric Water Using …
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