Intervening in academic interventions: framing social marketing's potential for successful sustainable tourism behavioural change

Aviation emissions contribute to the radiative forcing (RF) of climate. Of importance are emissions of carbon dioxide (CO2), nitrogen oxides (NO x ), aerosols and their precursors (soot and sulphate), and increased cloudiness in the form of persistent linear contrails and induced-cirrus cloudiness. The recent Fourth Assessment Report (AR4) of the Intergovernmental Panel on Climate Change (IPCC) quantified aviation's RF contribution for 2005 based upon 2000 operations data. Aviation has grown strongly over the past years, despite world-changing events in the early 2000s; the average annual passenger traffic growth rate was 5.3% yr−1 between 2000 and 2007, resulting in an increase of passenger traffic of 38%. Presented here are updated values of aviation RF for 2005 based upon new operations data that show an increase in traffic of 22.5%, fuel use of 8.4% and total aviation RF of 14% (excluding induced-cirrus enhancement) over the period 2000–2005. The lack of physical process models and adequate observational data for aviation-induced cirrus effects limit confidence in quantifying their RF contribution. Total aviation RF (excluding induced cirrus) in 2005 was ∼55 mW m−2 (23–87 mW m−2, 90% likelihood range), which was 3.5% (range 1.3–10%, 90% likelihood range) of total anthropogenic forcing. Including estimates for aviation-induced cirrus RF increases the total aviation RF in 2005–78 mW m−2 (38–139 mW m−2, 90% likelihood range), which represents 4.9% of total anthropogenic forcing (2–14%, 90% likelihood range). Future scenarios of aviation emissions for 2050 that are consistent with IPCC SRES A1 and B2 scenario assumptions have been presented that show an increase of fuel usage by factors of 2.7–3.9 over 2000. Simplified calculations of total aviation RF in 2050 indicate increases by factors of 3.0–4.0 over the 2000 value, representing 4–4.7% of total RF (excluding induced cirrus). An examination of a range of future technological options shows that substantive reductions in aviation fuel usage are possible only with the introduction of radical technologies. Incorporation of aviation into an emissions trading system offers the potential for overall (i.e., beyond the aviation sector) CO2 emissions reductions. Proposals exist for introduction of such a system at a European level, but no agreement has been reached at a global level.

Despite extensive evidence of climate change and environmental destruction, polls continue to reveal widespread denial and resistance to helping the environment. It is posited here that these responses are linked to the motivational tendency to defend and justify the societal status quo in the face of the threat posed by environmental problems. The present research finds that system justification tendencies are associated with greater denial of environmental realities and less commitment to pro-environmental action. Moreover, the effects of political conservatism, national identification, and gender on denial of environmental problems are explained by variability in system justification tendencies. However, this research finds that it is possible to eliminate the negative effect of system justification on environmentalism by encouraging people to regard pro-environmental change as patriotic and consistent with protecting the status quo (i.e., as a case of "system-sanctioned change"). Theoretical and practical implications of these findings are discussed.