Striking the balance: Farmers' responses to coal seam gas and climate change

Abstract

Anthropogenic climate change is defined as "a change of climate which is attributed either directly or indirectly to human activity, which alters the composition of the atmosphere" (UN Framework Convention on Climate Change, Article 1, as cited in Pielke, 2004, p. 515). Approximately two-thirds of global anthropogenic greenhouse gas emissions are generated by the combustion of fossil fuels within the energy sector (International Energy Agency, 2015). The dominant contribution of fossil fuel combustion to anthropogenic emissions began around 1920 and has increased up to the present (Le Quere et al., 2015). These anthropogenic emissions are over and above the naturally occurring carbon cycle, which results in carbon being released into the atmosphere, hydrosphere and terrestrial biospheres (Archer et al., 2009). One of the primary drivers of global anthropogenic climate change is carbon dioxide, of which approximately 35 billion tonnes was released globally during 2011 (Peters et al., 2012). Globally, total greenhouse gas emissions were estimated to have reached 49.5 billion tonnes of carbon dioxide equivalents (CO₂eq) in 2010 (Victor et al., 2014). However, carbon dioxide is not the only anthropogenic greenhouse gas. The bacterial processing of both organic and inorganic inputs, and residual outputs of agriculture results in the release of a significant amount of methane, and nitrous oxide into the atmosphere (Smith et al., 2014). These agricultural non-CO₂ gases are estimated to contribute 5.2-5.8 billion tonnes CO₂eq/yr, or 10-12% of the total anthropogenic emissions (Smith et al., 2014).