Geneva: UN scientists have warned that the world is not on track to limit global warming to 1.5 degrees Celsius, stating that limiting global warming to 1.5 degrees Celsius is out of reach unless immediate and deep emissions reductions across all sectors are implemented.
On Monday, the Intergovernmental Panel on Climate Change (IPCC) Working Group III, in its report on Climate Change 2022: Mitigation of Climate Change, stated that limiting global warming will require major transitions in the energy sector, and this will involve a substantial reduction in fossil fuel use, widespread electrification, improved energy efficiency, and use of alternative fuels (such as hydrogen).
Stressing the urgency of emission reductions, the report noted that to meet the 1.5 degree target, net CO2 emissions should be zero by the early 2050s. Even if the target is only 2 degrees C, global greenhouse gas emissions should not rise after 2025 (they must start falling) at the latest, and must be reduced by a quarter by 2030.
The report notes that since 2010, “there have been sustained decreases of up to 85 percent in the cost of solar and wind energy, and batteries.” An increasing range of policies and laws have enhanced energy efficiency, reduced rates of deforestation and accelerated the deployment of renewable energy. “
The IPCC report was approved by 195 member governments of the IPCC through a virtual approval session that started on March 21.
It is the third instalment of the IPCC’s Sixth Assessment Report (AR6), which will be completed this year.
The previous reports of Working Groups I and II—released last year and earlier this year—dealt with the “physical science basis” for climate action and “adaptation,” referring to the measures that are to be taken to cope with inevitable climate change effects.
Taking about the report, IPCC Chair Hoesung Lee said, “We are at a crossroads.” The decisions we make now can secure a liveable future. We have the tools and know-how required to limit warming. “
He added that “I am encouraged by the amount of climate action being taken in many countries. There are policies, regulations, and market instruments that are proving effective. If these were scaled up and applied more widely and equitably, they could support deep emissions reductions and stimulate innovation. “
“Having the right policies, infrastructure, and technology in place to enable changes to our lifestyles and behaviour can result in a 40–75% reduction in greenhouse gas emissions by 2050. This offers significant untapped potential, “said IPCC Working Group III Co-Chair Priyadarshi Shukla. “The evidence also shows that these lifestyle changes can improve our health and wellbeing.”
“We see examples of zero-energy or zero-carbon buildings in almost all climates,” said IPCC Working Group III Co-Chair Jim Skea. “Action in this decade is critical to capture the mitigation potential of buildings.”
The scenarios we assessed, limiting warming to around 1.5°C (2.7°F) requires global greenhouse gas emissions to peak before 2025 at the latest, and be reduced by 43% by 2030; at the same time, methane would also need to be reduced by about a third.
Even if we do this, it is almost inevitable that we will temporarily exceed this temperature threshold but could return to it by the end of the century.
“It’s now or never if we want to limit global warming to 1.5 °C (2.7 °F),” said Skea. “Without immediate and deep emissions reductions across all sectors, it will be impossible.”
The global temperature will stabilise when carbon dioxide emissions reach net zero. This means achieving net zero carbon dioxide emissions globally in the early 2050s for 1.5°C (2.7°F), and in the early 2070s for 2°C (3.6°F).
This assessment shows that limiting warming to around 2 °C (3.6 °F) still requires global greenhouse gas emissions to peak before 2025 at the latest, and be reduced by a quarter by 2030.
The report looks beyond technologies and demonstrates that while financial flows are a factor of three to six times lower than the levels needed by 2030 to limit warming to below 2 °C (3.6°F), there is sufficient global capital and liquidity to close investment gaps.
However, it relies on clear signalling from governments and the international community, including a stronger alignment of public sector finance and policy.
Without taking into account the economic benefits of reduced adaptation costs or avoided climate impacts, global gross domestic product (GDP) would be just a few percentage points lower in 2050 if we take the actions necessary to limit warming to 2 °C (3.6°F) or below, compared to maintaining current policies, “said Shukla.
The next few years are critical, say the researchers, because if emissions aren’t curbed by 2030, it will make it nigh on impossible to limit warming later this century.
The key to that in the short term will be how we generate energy. Luckily, solar panels and wind turbines have never been cheaper, having fallen in cost by around 85% over the past decade.
It’s “game over for the fossil fuels that are fuelling both wars and climate chaos,” said Kaisa Kosonen from Greenpeace, who was an observer at the IPCC approval session.
“There’s no room for any new fossil fuel developments, and the coal and gas plants we already have need to close early.”
But diets and lifestyles will also need to change, with huge scope for major carbon savings, according to the authors.
“Having the right policies, infrastructure, and technology in place to enable changes to our lifestyles and behaviour can result in a 40–75% reduction in greenhouse gas emissions by 2050. This offers significant untapped potential, “said IPCC Co-chair Priyadarshi Shukla.
“The evidence also shows that these lifestyle changes can improve our health and wellbeing,” he said.
The Working Group III report provides an updated global assessment of climate change mitigation progress and pledges and examines the sources of global emissions.
It explains developments in emission reduction and mitigation efforts, assessing the impact of national climate pledges in relation to long-term emissions goals.