The agreement in Durban to establish a new body to negotiate a global agreement (Ad Hoc Working Group on the Durban Platform for Enhanced Action) by 2015 represents a major step forward. The Climate Action Tracker scientists stated, however, that the agreement will not immediately affect the emissions outlook for 2020 and has postponed decisions on further emission reductions. They warned that catching up on this postponed action will be increasingly costly.
The Climate Action Tracker estimates that global mean warming would reach about 3.5°C by 2100 with the current reduction proposals on the table. They are definitely insufficient to limit temperature increase to 2°C.
A warming over 3°C could bring the world close to several potential global-scale tipping points, such as:
Possible dieback of the Amazon rainforest
Corals reefs being irreversibly replaced by algae and sea grass
Irreversible loss of the Greenland ice sheets of many centuries to thousands of years
Risk of release of methane hydrates in ocean floor sediments further adding to the warming
Permafrost thawing due to fast rising arctic temperatures
A depiction of the types of impacts likely from 1.5°C of warming, through 2°C and 3-4°C has been posted on the Climate Action Tracker website today.
The costs for adaptation and the residual damages from climate change will increase rapidly with warming. Approximate estimates indicate that the most extreme costs will be felt in West Africa and South Asia, with residual damage of 3.5% of regional GDP for 2°C warming and 5-6% for 3°C warming. With a 2°C warming, adaptation costs would be half those associated with a 3°C temperature rise.
The Climate Action Tracker today released an infographic to show the range of impacts that the world risks on a pathway to well over 3°C and beyond.
“What is positive in Durban is that governments have reopened the door to a legally binding global agreement involving the world’s major emitters, a door which many thought had been shut at the Copenhagen Conference in 2009,” said Bill Hare, Director of Climate Analytics.
“What remains to be done is to take more ambitious actions to reduced emissions, and until this is done we are still headed to over 3oC warming. There are still no new pledges on the table and the process agreed in Durban towards raising the ambition and increasing emission reductions is uncertain it its outcome.”
“There are still options available to close the gap between current globally planned mitigation and what is needed to hold warming below 1.5 or 2°C – if action takes place fast,” said Niklas Höhne, Director Energy and Climate Policy at Ecofys. “Emission reduction options are rapidly diminishing.”
Download the full briefing here