CLIMATE CHANGE: A 1994 SCIENCE SUMMARY

Abstract

New observations of the chemical composition of the atmosphere are reshaping scientific understanding of the global sources and sinks of the greenhouse gases. Current trends in the atmospheric concentrations of some of these gases are reviewed, with reference to new work emerging from Antarctic ice cores.

Accompanying an understanding of the composition of the atmosphere, is the need to understand the processes which drive the global climate system, including interactions between the atmosphere and oceans. Studies of climatic processes therefore form the scientific underpinning for the development of numerical models that describe the response of the global climate system to observed changes in the composition of the atmosphere.

Success or failure in efforts to improve model simulations can be assessed using a variety of objective statistical tests. Examples of such tests show demonstrable progress in the ability of global climate models to simulate the present day climate realistically.

Since confidence in the regional details of climate predictions from climate models is low, considerable effort is being devoted to developing models capable of providing improved regional estimates of climate change and in practice a variety of models not limited to the global-scale models are used in this work. In the meantime, several approaches to assessing the potential impacts of climate change are possible. These are discussed with special reference to tropical cyclones and east coast lows.

Throughout this review emphasis is placed on recent Australian contributions to the field, most notably work conducted within CSIRO.