The Carbon Challenge
From mid 2008, a series of scientific papers provided evidence that the capacity of the atmosphere to absorb additional emissions safely was far less than previously thought. Avoiding dangerous climate change would require a lot more effort, and achieving a ‘safe’ concentration of greenhouse gases (likely to be under 350 ppm CO2) would require some carbon already resident in the atmosphere to be returned to earth.
Global initiatives to secure emission reductions have had little success. Current pledges by developed countries to reduce emissions by 2020 would allow ‘Business as Usual’ levels once ‘loopholes’ are accounted for. And New Zealand’s response has been among the weakest for a developed country.
As incremental change has not taken hold in time, nations are now exposed to sudden change at the point social systems catch up with climate physics. New Zealand has a wealth of options for reducing emissions but is currently in an exposed position with rising gross emissions.
New Zealand needs to establish a carbon budgeting process to set long term plans for decarbonising the economy and building resilience to shocks. Carbon budgeting integrates the ETS, complementary measures, and financial limitations to secure long-term goals.
The Carbon Budget Deficit (2012)