In both foehn cases the surface variables exhibit clear diurnal signatures, with the shortwave radiative (SW) flux dominating the SEB (Figure 11(a,b)), and melt apparent exclusively duringthe day (Figure 11(c,d)). Ice melt during foehn conditions is a result of positive SW fluxes due to the ‘foehn clearance’ of clouds and positive sensible heat (SH) fluxes due to the warmth ofthe foehn air and strong winds. The consistently greater surface temperatures and net downward surface fluxes during case C are due to greater surface SH fluxes (by 30 W m−2 on average) – aresult of the warmer foehn air and strongerwinds – and, to a lesser extent, greater SW fluxes (by 14 W m−2 on average) as this case is closer to the southern solstice. The remaining two components of the SEB – the longwave and latent heat fluxes – cool the surface and generally have greater (negative) contributions to the SEB in case C, but not enough to offset the greater (positive) contributions of the two warming components.
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