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The level of ambition of the public and policy makers to protect the climate is currently far too low to slow the accelerating pace of climate impacts. Ambition can be strengthened using strategies that disaggregate the overall climate problem into manageable pieces, borrow existing laws and institutions to take fast action following a 'start and strengthen' approach. This is illustrated by the strategy to phase down the production and consumption of high global warming potential hydrofluorocarbons under the Montreal Protocol. Such an approach could cut the rate of global warming in half for the next several decades, and even more in the Arctic and other climate vulnerable regions. This can provide fast success and build the sense of urgent optimism needed to raise ambition to do more to address carbon dioxide emissions - the single largest contributor to climate change. [ABSTRACT FROM AUTHOR]

Most refrigerants used today are potent chlorofluorocarbon (CFC), hydrochlorofluorocarbon (HCFC), and hydrofluorocarbon (HFC), greenhouse gases (GHG) that can contribute significantly to anthropogenic climate change and stratospheric ozone depletion. In a business-as-usual scenario, HFC emissions in 2050 have been predicted to be equivalent to 9-19% (CO-eq. basis) of projected global CO emissions. This percentage increases to 28-45% if projected CO emissions result in a 450-ppm CO stabilization scenario. Half of current direct HFC emissions are from mobile air conditioning (MAC) and alternative refrigerants with lower global warming potential (GWP) should have higher energy efficiency. The European f-Gas Directive phases out the use of refrigerants with GWP > 150, including HFC-134a (GWP = 1430) from MACs by 2017. Life-Cycle Climate Performance (LCCP) identifies environmentally superior technology to minimize GHG emissions from refrigeration and air conditioning applications. The comprehensive LCCP model, GREEN-MAC-LCCP© focuses on the current choice among alternative refrigerants that meet the f-Gas requirement starting in 2011. Using GREEN-MAC-LCCP we estimate that the current MAC technology based on HFC-134a refrigerant demands additional fuel during vehicle A/C operation in the: USA by 7%, in the EU by 7%, in Japan by 9%, in India by 15-20%, and in China by 7-10% depending on the humidity. We compare these data with the projected LCCP CO-eq. savings by the year 2017 when HFC-134a will be replaced by a low GWP alternative (GWP < 150) according to the f-Gas rule. We find that refrigerant HFO-1234yf has the potential to reduce global LCCP CO-eq. greenhouse gas emissions by about 7% in 2017, whereas greenhouse gas emissions from air conditioning systems using R-744 (carbon dioxide) refrigerants are estimated to be about 2% greater, compared to the current HFC-134a MAC baseline systems. © 2010 American Institute of Chemical Engineers Environ Prog, 2011 [ABSTRACT FROM AUTHOR]