Consequently, whilst Obama’s proposition is certainly brave within the rarified political environment of Congress, it signals yet another wealthy nation whose weak domestic targets are fatally undermining international obligations around 2°C. The low level of ambition of the US, EU, Russia, China et al is why global emissions are set on a pathway much more aligned with a 4°C to 6°C future (~RCP8.5) than the 2°C of our rhetorical targets. Moreover, given that temperatures relate to the cumulative build up of CO2 in the atmosphere, failure to radically reduce emissions in the short-term locks in higher temperatures and “dangerous” impacts, particularly for “poorer populations“. Ramping up the mitigation effort post 2030 will simply be too late. This is a challenging message with implications for policy makers (and all of us) that we have thus far refused to countenance.
So whilst the science and maths around 2°C provides an unequivocal basis for radical reductions in emissions from wealthier nations, the politics continues to deliver grand but ultimately ineffectual gestures. Politically Obama’s proposal is certainly courageous and one for which he deserves credit. But scientifically, the 30% target and the collective acquiescence it has triggered, is a death sentence for many of tomorrow’s more vulnerable communities.