Figure 7: Average diurnal cycle
of (top) latent heat flux, (middle) sensible heat flux, and (bottom)
Bowen ratios, with the interquartile (dark shading) and the 10 to 90
quantile zones (light shading). The left column are data for January to
mid-May (ice cover), the central column covers mid-May to August (heat
storage), and the right column covers September to December (heat
release). Note that the range of the ordinate values varies from one
plot to the other. All times are local.
Condensation episodes (LE < 0 W m−2)
occurred occasionally throughout the study period. During winters, small
and short condensation episodes occurred almost every day. However,
during the vernal turnover, conditions became very stable and the
atmosphere was much warmer than the water surface, which was nearly
constant at 4°C. Consequently, only a few condensation events were
recorded between 1 May and 17 July, with cumulative amounts of 2.2 mm,
0.6 mm and 3.4 mm in 2019, 2020 and 2021, respectively. Figure 8
presents examples of condensation events that occurred in June,
temporarily reaching –10 W m−2 or 0.35 mm
day−1.