JUNIOR CLUSTER DESCRIPTION
Students are barraged on a daily basis with news stories of El Nino, global warming, CO2 increasing, greenhouse effects, ozone hole, etc. This cluster will introduce some of the scientific concepts and issues of natural global cycles and how the systems have changed in the past. We will discuss the physical, chemical and biological changes of the earth's environment in the past, present and future. The past will concentrate on the physical, chemical and biological changes that are recorded in the rock, ice and sediment record. The present will concentrate on recent changes on the oceans and atmosphere, and discuss the human dimension. The future will discuss the merits and limits of global models.