Introduction
This unit explores the topic of climate change and global warming. We will begin by exploring how the Earth’s global mean surface temperature is determined through a global “balancing act” of the rate of energy that comes from the Sun and the rate at which the planet returns that energy into space. We will also discuss the natural greenhouse effect, and how this contributes to a balanced global climate. We will then go on to consider the human impact on the atmosphere, including the impact of industrialisation, other sources of greenhouse gases that are connected to humans and the numerous and varied means of measuring climate change that are available.
Learning Outcomes
Having studied this unit you should:
- understand the physical basis of the natural greenhouse effect, including the meaning of the term radiative forcing;
- know something of the way various human activities are increasing emmissions of the natural greenhouse gases, and are also contributing to sulphate aerosols in the troposphere;
- be aware of the difficulties involved in the detection of any unusual global warming ‘signal’ above the ‘background noise’ of natural variability in the Eath's climate and of attributing (in whole or in part) any such signal to human activity;
- understand that although a growing scientific consensus has become established through the IPCC, the complexities and uncertainties of the science provide opportunity for climate sceptics to challenge the Panel's findings.