The Upper Tisa Valley. Preparatory proposal for Ramsay

Figure 10 Annual mean values of precipitation in mm in the catchment area of the
Upper Tisa and River Bodrog on the basis of 20 years of survey data (see figure 9)
at this time of year rather than thaw. Intensive increase of surface water-input in the
highest regions start only in April. At that time figures of around 100-300 mm are
common in the Northwestern Carpathian region. In plain and hilly areas amounting to
the bulk of the drainage basin it is rainfall that provides the sole source of surface
water input in April. In the catchment area system there are sharp differences between
basins, dry valleys and mountainous areas. In May this extreme condition lessens to a
great extent: rainfall accounts for the entire surface water input in the region. In higher
areas of the mountain ranges the considerable melt and rainfall result in a significant
increase in the water input. At altitudes higher than 2000 m, for instance, there are
figures exceeding 200 mm.
In the summer months (June, July, August) it is rainfall that provides surface
water input everywhere, except in the regions above the snow line. Very high values
result (600-700 mm). In the catchment area most of the rainfall is received by the
northwestern and northern slopes. In the catchment area system monthly average
exceeds even 200 mm, while in the area of the intermediate basins, on the surface of
the plain, figures are only about 50 mm. With the comparatively dry weather conditions
of July and August, water input of the drainage basin does not decrease here.
On the western slopes of the Northeastern Carpathians figures reach even 100-
150 mm, in most of the Great Plain, however, figures under 50 mm are observed. Due
to the continental effect in August, sources of water input significantly diminish in the
whole area.
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