The Upper Tisa Valley. Preparatory proposal for Ramsay

Figure 9. Locations of pluviometric stations in the catchment area of the Upper Tisa
and River Bodrog, having data over 20 years
In January the regional distribution of precipitation is similar to that of
December. At altitudes above 1000-1500 m monthly data show less than 15 mm as
well, at altitudes above 2000 m we practically cannot speak of surface water-input due
to sub-zero temperatures. In the wetter southwestern slopes of the drainage basin, due
to mild winters, we can normally expect monthly figures to be about 30 mm. In the
last month of winter (February) frequent melting that causes considerable increase in
the flowage of water resources from certain areas is the only change in the monthly
averages of surface water. In mountainous regions reaching altitudes higher than 2000
m we can reckon water input mainly at 15 mm, while 30 mm can only be observed in
areas at altitudes lower than 1000 m.
Surface water-flow of the spring season (March, April, May) shows a dynamic
picture. Snow-melting in spring triggers a significant increase in the surface water
input from March to April. In March, for example, in most of the catchment area thaw
peaks and the figure of surface water input increase considerably compared with the
preceding months. In areas between altitudes of 500 m and 1500 m the average
monthly figure can generally be set at about 100 mm. Figures of the leanest water
input are experienced in the Great Plain and in some regional basins, where monthly
averages are merely about 15 mm. Regions situated 2000 m or higher above sea level
are considered unfavourable areas, where there is still a process of snow accumulation
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