The combined effects of surface temperature and precipitation changes are such that snow cover is reduced by up to 50% on average, causing large changes in the seasonal runoff.
(The combined effects of surface temperature and precipitation changes; are; such that snow cover is reduced by up to 50% on average) (snow cover; is reduced; by up to 50%; causing large changes in the seasonal runoff)
The combined effects of surface temperature and precipitation changes snow cover
are is reduced
such that snow cover is reduced by up to 50% on average
by up to 50% causing large changes in the seasonal runoff