3. Results
3.1. Fit of air water temperature model
The air water temperature model showed a good fit to
all four water bodies (Fig. 1). For the large and relatively
deep Lake IJsselmeer, the explained variance in water
temperaturewas 98.1%and the residual standard deviation
0.86 °C (Table 2). For the intermediate sized and shallow
LakeTjeukemeer explained variance and residual standard
deviation were 97.5% and 0.94 °C, respectively. For the
small and shallow Lake Zwemlust, these data were 94.7%
and 1.47 °C, respectively. To our surprise, the model fitted
best for the tidal inlet with an explained variance of 98.7%
and a residual standard deviation of 0.61 °C.
The model showed a comparable good fit throughout
the season in IJsselmeer and Tjeukemeer. In Zwemlust,
however, the model fitted less well in summer compared
with other seasons, reflected in higher residual deviations in
summer. In Marsdiep a small seasonal deviation between
data and model not captured by the sinus was observed.