Carbon dioxide reductions are key, but the IPCC’s latest report highlights the benefits of making cuts to other greenhouse gases, too.
There’s no substitute for eliminating fossil fuels and halting the release of carbon dioxide into the atmosphere to avoid the painful and disruptive effects of global warming. The latest report from the Intergovernmental Panel on Climate Change (IPCC) leaves no doubt about this. But CO2 is not the only greenhouse gas. The climate panel also highlights the problem — and opportunity — posed by methane, which has contributed as much as 0.5 °C of warming since pre-industrial times, second only to CO2.
The report paints an alarming picture but emphasizes there is still time for swift action to mitigate the worst of the projected impacts of climate change. Current average warming is now estimated at 1.1°C compared to preindustrial records, a revision based on improved methods and data that adds 0.1°C to previous estimates. Under every emissions scenario explored by the report, average warming of 1.5°C—a major target of the Paris climate accord—will very likely be reached within the next 20 years.
The United Nations is poised to release the most confident and comprehensive assessment yet of global warming, including detailed estimates of how continued greenhouse-gas emissions will increase Earth’s sea levels and drive extreme weather in the coming years. Compiled by more than 200 scientists and approved by government representatives from 195 countries, the report from the Intergovernmental Panel on Climate Change (IPCC) will leave little doubt that humans are altering the way the planet functions — and that things will get much worse if governments do not take drastic action, say climate researchers interviewed by Nature.
Many hope that the report, which covers the latest advances in climate science, will galvanize action at the UN climate summit in Glasgow, UK, this November, where world leaders will make fresh commitments to curbing greenhouse-gas emissions. Scientists say that on the basis of current policies, governments will fail to meet the goals they set in the 2015 Paris climate accord to limit global warming to 1.5–2 °C above pre-industrial levels.
MARIO MOLINA CENTER FOR STRATEGIC STUDIES ON ENERGY AND THE ENVIRONMENT CDMX