Assessing the water balance of Hungary in the shadow of climate change

Abstract

Global warming induces an increasing demand for evaporation. The largest components of the water balance equation in Hungary are precipitation on the input side, and evapotranspiration on the output side (excluding the rivers flowing through the country). The role of evaporation needs to be redefined from a simple loss factor to an important ecological service that enables the distribution of climatic energy. This invisible service protects the surface from overheating. Due to global warming evapotranspiration must be increased on land to meet the growing need of climatic energy transport, exceeding all current consumption by population, industry and agriculture. We must renew our concepts about evapotranspiration before it is too late. An integrated, system-orientated atmospherehydrosphere model is urgently needed. We must not fall into the pointless trap of competing for water between civilization and natural processes. This can be avoided by increasing the ratio of active transpiration through vegetation compared to passive evaporation from the surface. Human civilisation has become capable of influencing the hydrological cycle and challenge its stability. Providing access to water is by no means the only task of the water infrastructure sector. Keeping enough water in the hydrological cycle for both natural processes and civilizations is the way to ensure water security. This huge task requires an unprecedent effort and collaboration across many fields, including education, research and many other sectors of our lives. With this approach the role of the water sector gains a new perspective: it can be a pioneer and engine of much needed and urgent favourable changes. Kulcsszavak Hydrological cycle, climate change, evaporation, evapotranspiration, climatic water demand, ecological services, surface temperature, short water cycle, water security.