The last two decades showed an introduction of world-wide threats to the biosphere and human health due to the effects of anthropogenic activities. This book pays attention to ecological and geophysical aspects of controlling the natural environment. The scientific basis of observations, assessment and forecasting of this natural environment are treated extensively. Methods of ecological and climatic monitoring are presented and their realization in several countries are discussed. Analysis of possible climatic changes, the ozone-layer problems, the polluting of the oceans, acid rain and the aftermath of the Chernobyl accident are concrete examples presented.