Lago Maggiore

The measurements for this Lago Maggiore scenario were made during three days in winter 1995 (December 18-21) at the shore of Ispra (45$ ^{\circ}$ 49,244'N, 8$ ^{\circ}$ 36,377'E). The measurements were carried out with an uprising profiler located 150 m from the shore at a water depth of 42 m. Such the sampled depth interval ranged from 30 m up to the surface. On the profiler, an MST shear probe, a fast temperature sensor and temperature and conductivity probes were mounted such that profiles of turbulent dissipation rate $ \epsilon$, temperature variance $ \epsilon_\theta$, mean temperature $ \theta$ and mean salinity $ S$ could be derived. For a detailed description of the data analysis, see Stips et al. (2002).

Wind speed was measured from a small buoy about 30 m away from the probe location with an anemometer at a height of 95 cm above the water surface. The accuracy is $ \pm 0.1$ ms$ ^{-1}$. Air temperature and relative humidity were recorded at the measurement location on shore at a height of 10 m above lake surface. The cloud cover has been estimated every hour. Incident solar radiation was measured at the meteorological station in Pallanza, in a distance of about 10 km from the measuring site. An analysis of heat fluxes obtained by various bulk formulae showed however a significant deviation between the heat content of the water column and accumulation of these heat fluxes. This could be due to the fact that these bulk formulae are designed for oceanic conditions such that they are not valid for a lake with weak wind conditions. Thus, instead of using the calculated surface heat fluxes from bulk formulae, they were calculated from the heat gain of the water column under consideration of the solar radiation.

Data files:

salz_lmd95.dat profiles of measured salinity in ppt for initial conditions and relaxation
temp_lmd95.dat profiles of measured potential temperature for initial conditions and
eps_lmd95.dat profiles of measured dissipation rate for validation
hflu2_05lt.dat surface heat fluxes calculated according to Kondo (1975)
momentumflux.dat surface momentum fluxes calculated according to Kondo (1975)

For a discussion of the simulation, see Stips et al. (2002).

Karsten Bolding 2012-01-24