The surface of the Earth is heated by solar radiation (shortwave radiation) passing through the atmosphere. The air near the earth’s surface is heated from below using this energy converting the shortwave radiation to other forms. According to the law of conservation of energy, the incoming and outgoing energies are equal. Continents are warming faster than the global average warming as published in an IPCC 2019 report. These facts encourage us to examine energy transport processes and their changes applying Ludwig von Bertalanffy’s General System Theory. The input of the system is net shortwave radiation and the outputs are distributing this energy via different processes after transformation (thermal radiation, sensible heat and latent heat).
Major terms of this surface energy distribution system are compared in the Danube Region in two thirty-year periods. The energy input to the system has increased, resulting in an increase on the output side as well. If we use the evaporation fraction as an indicator to evaluate the performance of the distribution process, we can see that the efficiency of the distribution process – illustrated by the Climatic Energy Balance Diagram – is roughly the same. However, this is not enough to remove the increased energy from the surface: both latent heat and sensible heat have increased.
If we decompose the energy increase between the two periods into components on the output side, another problem becomes visible. The excess energy no longer leaves the surface in the form of evaporation at the same rate as before, but at a smaller rate, and the proportion of energy converted into sensible heat increases. In summer the availability of water for evaporative cooling becomes a problem. The role of plants and transpiration is being appreciated, a paradigm shift is needed. They provide the most important environmental services.