ABSTRACT
The environmental manager needs to understand the structure and function of the environment to be able to assess the effect of human activities. Such knowledge is incomplete and/or data collection has been inadequate so forecasting and decision making are often far from perfect. Nevertheless, compared with the situation before the International Geophysical Year (1957-8), there is much more knowledge on the structure and function of the environment, but reliable and comparable data on physical and human conditions are still often hard to come by.
