Abstract: The Sun, our Sun, is our main source of energy. But Sun has also the sunspots. Energy is the light side of the Sun-planet interaction, the shadow is a bi-effect, sometimes called entropy, it is the negative aspect of this energy which Sun sends to our planet. The world sees nowadays an increasing global warming period which in its turn has been attributed to heliogenic and/or anthropogenic effects. The cyclic nature of the influence of Sun on earths climate is discussed. Also the expected Sun activity maximum of the year 2012 and further NASA forecasts for the coming years until the end of the 25th Sun cycle are presented and discussed. We show that the cycles of Nature are the most important but also that the anthropogenic effects could damage the sensitive balance which is the outcome of the interplay between the natural forces and Man, a balance which was kept in the long history of the mankind, but now in the last decades is seriously threatened.

Brief Biography of the Speaker:

MSc Chemical Engineer NTUA Athens 1971, PhD Food Engineering, Lund , 1987, Sweden. Vassilis Gekas is Professor of Transport Phenomena amd Directore of the Transport Phenomena & Environmental Thermodynamics at the Technical University of Crete.
He gained international reputation in the Membrane Technology both the synthetic and biological membranes. Author of the CRC edited book of "Transport Phenomena of Foods and Biological Materials " , boca Ratomn FL, 1992. Author of several books in Greek. He was the first to be chairman of the Environmental Engineering dpt , 1984- 2003. He deals with teaching and research in the following fields: Renewal energy sources, desertification, unit operations with developing of Greek raw materials , recovery of high added value constituents from agro-food wastes, enzymatic conversion of starch, thermal treatment of solid wastes, solar cooling. His approximately 50 publications in international journals gained the attention of approximately 1000 colleagues (CI=1000).