Global greenhouse gas reduction efforts not enough, IPCC says
"A wide array of technological measures and changes in behaviour"
Governments, businesses and consumers must work together to reduce climate-warming greenhouse gas emissions, the United Nations’ Intergovernmental Panel on Climate Change said in its latest report, issued April 13 in Berlin.
“To avoid dangerous interference with the climate system, we need to move away from business as usual,” said Ottmar Edenhofer, co-chair of the latest IPCC report, which shows global emissions of greenhouse gases have risen to “unprecedented levels” despite a growing number of policies to reduce climate change.
Scientists say the “business-as-usual” way of doing things will condemn the Arctic to average temperatures in 2100 ranging from 9 C to 16 C higher than today.
Greenhouse gas emissions grew more quickly between 2000 and 2010 than in each of the three previous decades, the IPCC said in its latest summary report for policymakers.
Emission reductions are still possible, so the global temperature increase can be held to 2 C, said the report, produced by 1,250 international experts and approved by 194 governments.
But sticking with that level will require “a wide array of technological measures and changes in behaviour,” to limit the increase in global mean temperature to 2 C above pre-industrial levels.
In the Arctic, average annual temperatures are predicted to rise three to six degrees higher than today by 2100.
Even to remain within this range of increase, the world needs to lower global greenhouse gas emissions by 40 per cent to 70 per cent of 2010 levels by 2050, and to near-zero by the end of this century, the IPCC said.
This could involve a move to using other forms of energy, such as nuclear power, wind energy and biofuels.
But developing and switching to these alternatives will come with a cost, such as lower economic growth.
“However, only major institutional and technological change will give a better than even chance that global warming will not exceed this threshold,” Edenhofer said.
The report, entitled Climate Change 2014: Mitigation of Climate Change, is the third of three reports, part of the IPCC’s Fifth Assessment Report on climate change, which will be released in October 2014.
The second of its reports found that climate change will leave no one untouched.
Mitigation, or human intervention to reduce greenhouse gas emissions, won’t be easy to carry out, as recently there’s little progress on adopting a binding international agreements.
In its latest report the IPCC says that any areas of climate policy involve value judgments and ethical considerations.
These areas range from the question of how much mitigation is needed to prevent dangerous interference with the climate system to choices among specific policies for mitigation or adaptation.
But if the world waits until 2030 to take any action, some scientists say the global temperature will increase by 4.5 C and by up to 5.5 C over land, bringing a host of “dangerous” impacts, such as the near-total melt of the Greenland ice sheet.