The Upper Tisa Valley. Preparatory proposal for Ramsay

Figure 14. A map of the density of natural watercourses in the catchment area of River
Tisa
Volumes of flowage in the catchment area hugely depend on the features of the
surface relief (angle of slope, exposure, perviousness, proportion of area covered by
plants, etc.). One of the most essential factors influencing the density of the
watercourses and the dynamics of surface erosion (stage of valley formation) is the
relief energy of the region, which primarily exerts its influence in the river system in a
way that the higher the figure is, meaning the more marked the features of relief are
and the higher the slopingness is, the denser and richer the river system taking shape
will be.
The mountain ranges of the Carpathians have a powerful and complex effect on
the distribution of atmospheric movements. 1500-2000 m high relief formations
constitute real obstacles to air masses coming towards them. Mountain ranges
significantly alter the direction of cyclones as well as their natural formation. Passing
cyclones moving over the ridges often separate to meet again later in less turbulent
zones.
Within air masses forced into an ascending course, intense adiabatic cooling
occurs, which, in turn, results in the creation of precipitative activities in the
mountainous areas, even in the case of air masses that have proved to be absolutely
inactive and dry over the Great Plain.
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