ABSTRACT
Scientific understanding and concern about climate change has increased worldwide over the past two decades and featured prominently in high-profile international policy debates. In the same year that the United Nations (UN) Intergovernmental Panel on Climate Change (IPCC) was awarded the Nobel Peace Prize (2007), its Fourth Assessment Report (AR4) concluded that the global climate has changed over the last 150 years and is anticipated to continue to change over the twenty-first century and beyond. The IPCC declared that ‘warming of the climate system is unequivocal’ and the observed increase in global average temperatures since the mid-twentieth century ‘very likely’ the result of human activities that are increasing greenhouse gas (GHG) concentrations in the atmosphere (Solomon et al. 2007). The conclusions of the IPCC have been reinforced by more recent studies on the state of the global climate system (e.g. NOAA 2010).
