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