To stave off temperature increases that could pose immense risk, more forceful action is needed to trim anthropogenic greenhouse gas emissions – beginning now – according to the latest in a series of new reports from the UN’s Intergovernmental Panel on Climate Change.
The report says the required remaking of the global energy picture can be undertaken at a cost that would trim annual baseline growth rates – anticipated to be between 1.6 and 3 percent over the course of the century – by around 0.06 percent, a figure that does not take into account the economic benefits of reduced climate change.
“Many different pathways lead to a future within the boundaries set by the two degrees Celsius goal,” working group co-chair Ottmar Edenhofer said in a statement [PDF]. “All of these require substantial investments. Avoiding further delays in mitigation and making use of a broad variety of technologies can limit the associated costs.”
A summary of the IPCC’s “Climate Change 2014: Mitigation of Climate Change” report [PDF] released this week says that progress made since the UN last reported on mitigation, in 2007, has been too slow to turn the tide on the rising concentration of carbon dioxide in the atmosphere. In fact, the first decade of the new century saw more greenhouse-gas emissions than ever before.
“Total anthropogenic GHG emissions have continued to increase over 1970 to 2010 with larger absolute decadal increases toward the end of this period,” the report states.
It’s this reality, the report says, that requires a steep ramp-up in mitigation efforts. With “high confidence,” the report states: “Delaying mitigation efforts beyond those in place today through 2030 is estimated to substantially increase the difficulty of the transition to low longer‐term emissions levels and narrow the range of options consistent with maintaining temperature change below 2°C relative to pre‐industrial levels.”
A variety of actions are included in the scenarios under which CO2 levels stay low enough to avoid serious repercussions, beginning with how energy is generated.
The report strongly endorses renewable energy sources, like solar and wind, which it characterizes as having “demonstrated substantial performance improvements and cost reductions.” But while many climate change activists cheered the report for its “overall message” that “a rapid shift to renewable energy is needed to avert catastrophic global warming,” as Climate Progress put it, the report goes past renewables into areas where some greens are less comfortable.
The report consistently includes nuclear power in its decarbonizing scenarios, even as it allows that “a variety of barriers and risks exist” for nuclear power (look no further than Germany and Japan to verify that). Many climate change fighters have also grown skeptical of carbon capture and storage (CCS), both on its cost and long-term safety, but the report includes it in its under-2°C scenarios.
Energy efficiency, meanwhile, is a more generally palatable mitigation strategy (OK, there are some exceptions), and the report leans on it heavily to reduce energy use – and thus emissions – in the transportation, building, industry and general infrastructure sectors.