TABLE OF CONTENTS The range of issues which may need to be considered while preparing an environmental assessment is very large indeed. Some become relatively more important at one time than at another, while new problems arise constantly. It is for this reason, among others, that it is difficult to build into legislation or regulations a required set of items to be covered in every case. We present here seven contemporary issues which are currently important, and suggest ways in which consideration of these problems enter into an assessment. There are certainly many other problem areas which may be more important in certain instances, but each of these has some history of being relevant to national and international decision making. Issues examined are global warming, acid rain, deforestation, endangered species, biodiversity, cultural resources, and ecorisk.
Swedish chemist Svante Arrhenius (1896) coined the term greenhouse effect at the turn of the century. He postulated that if certain gases such as carbon dioxide were to be increased in the atmosphere due to combustion of fossil fuel, this would allow sunlight to penetrate, but retain outgoing infrared radiation, in a manner analogous to a greenhouse; this could cause appreciable global warming.
In the natural functioning of the earth s climate, atmospheric gases, most importantly water vapor and carbon dioxide, and less importantly methane, nitrous oxide, and ozone, trap solar heat reflected from the earth s surface and prevent it from escaping into space. Without this natural greenhouse effect, the earth...
