Between 2010 and 2019, global average annual greenhouse gas emissions were at their highest level in human history, but the rate of growth has slowed. Without immediate and deep reductions in emissions across all sectors, limiting global warming to 1.5°C is out of reach. However, there is growing evidence for climate action, scientists said in the latest report from the Intergovernmental Panel on Climate Change (IPCC) released today.
Since 2010, there have been sustained declines of up to 85% in solar, wind and battery costs. A growing range of policies and laws have improved energy efficiency, reduced deforestation rates and accelerated the deployment of renewable energy.
“We are at a crossroads. The decisions we make now can ensure a viable future. We have the tools and the know-how to limit warming,” said IPCC Chairman Hoesung Lee. “I am encouraged by the climate measures taken in many countries. There are policies, regulations and market instruments that are proving to be effective. If these are scaled up and applied more broadly and equitably, they can support deep emissions reductions and drive innovation. »
The Summary for Policymakers of the IPCC Working Group III report, Climate Change 2022: Mitigating Climate Change , was endorsed on 4 April 2022 by 195 IPCC member governments, during a virtual endorsement session that began on March 21. This is the third installment of the IPCC's Sixth Assessment Report (AR6), which will be completed this year.
We have options in all sectors to at least halve emissions by 2030
Limiting global warming will require major transitions in the energy sector. This will involve a substantial reduction in the use of fossil fuels, widespread electrification, improved energy efficiency and the use of alternative fuels (such as hydrogen).
“Putting the right policies, infrastructure and technologies in place to enable changes to our lifestyles and behaviors can lead to a 40-70% reduction in greenhouse gas emissions by 2050. This offers significant untapped potential,” said Priyadarshi Shukla, co-chair of IPCC Working Group III. “Evidence also shows that these lifestyle changes can improve our health and well-being. »
Cities and other urban areas also offer significant opportunities for reducing emissions. These can be achieved through lower energy consumption (e.g. by creating compact and walkable cities), electrification of transport in combination with low-emission energy sources and energy absorption. and increased carbon storage using nature. There are options for established, rapidly growing, and new cities.
“We see examples of zero-energy or zero-carbon buildings in almost every climate,” said Jim Skea, co-chair of IPCC Working Group III. “It is essential to act during this decade to capture the mitigation potential of buildings. »
Reducing emissions in industry will involve using materials more efficiently, reusing and recycling products, and minimizing waste. For basic materials, including steel, building materials and chemicals, processes for producing low to zero greenhouse gases are at pilot to near commercial stages.
This sector accounts for around a quarter of global emissions. Achieving net zero emissions will be challenging and will require new generation processes, low- or zero-emission electricity, hydrogen, and, if necessary, carbon capture and storage.
Agriculture, forestry and other land uses can reduce emissions on a large scale and remove and store carbon dioxide on a large scale. However, land cannot compensate for delays in emission reductions in other sectors. Response options can benefit biodiversity, help us adapt to climate change, and secure livelihoods, food and water, and wood supply.
The next few years are crucial
In the scenarios assessed, limiting warming to around 1.5°C (2.7°F) requires global greenhouse gas emissions to peak by 2025 at the latest and be reduced by 43% d by 2030; at the same time, methane should also be reduced by about a third. Even if we do this, it is almost inevitable that we will temporarily exceed this temperature threshold, but may return below 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),” Skea said. “Without immediate and deep emission reductions across all sectors, this will be impossible. »
Global temperature will stabilize when carbon dioxide emissions reach net zero. For 1.5°C (2.7°F), this means achieving net zero carbon dioxide emissions globally by the early 2050s; for 2°C (3.6°F), it's in the early 2070s.
This assessment shows that limiting warming to around 2°C (3.6°F) still requires global greenhouse gas emissions to peak by 2025 at the latest and be cut by a quarter by 2030.
Bridging investment gaps
The report looks beyond technologies and demonstrates that if 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 enough global capital and liquidity to fill investment gaps. However, it relies on clear signals from governments and the international community, including stronger alignment of public sector finance and policies.
“Without accounting for the economic benefits of reduced adaptation costs or avoided climate impacts, global gross domestic product (GDP) would be only a few percentage points lower in 2050 if we took the necessary steps to limit climate change. warming at 2°C (3.6°F) or less, relative to maintaining current policies,” Shukla said.
Achieving the Sustainable Development Goals
Accelerated and equitable climate action to mitigate and adapt to the impacts of climate change is essential for sustainable development. Some response options can absorb and store carbon and, at the same time, help communities limit the impacts associated with climate change. For example, in cities, networks of parks and open spaces, wetlands and urban agriculture can reduce flood risk and reduce heat island effects.
Mitigation in industry can reduce environmental impacts and increase jobs and business opportunities. Electrification with renewable energy and changes in public transport can improve health, jobs and equity.
“Climate change is the result of more than a century of unsustainable energy and land use, lifestyles, and consumption and production patterns,” Skea said. “This report shows how acting now can move us towards a fairer and more sustainable world. »
Additional information :
Climate Change 2022: Mitigating Climate Change. Contribution of Working Group III to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change
The report of Working Group III provides an updated global assessment of progress and commitments in mitigating climate change, and examines sources of global emissions. It explains the evolution of emissions reduction and mitigation efforts, assessing the impact of national climate commitments against long-term emissions goals.
Working Group III introduces several new elements in its latest report: one is a new chapter on the social aspects of mitigation, which explores the "demand side", i.e. what stimulates consumption and greenhouse gas emissions. This chapter is a partner to the report's sectoral chapters, which explore the 'supply side' of climate change – what produces emissions. There is also a cross-sectoral chapter on mitigation options that cut across all sectors, including carbon dioxide removal techniques. And there is a new chapter on innovation, technology development and transfer, which describes how a well-established innovation system at the national level, guided by well-designed policies, can contribute to the mitigation, adaptation and the achievement of the Sustainable Development Goals, while avoiding unintended consequences.
The Summary for Policymakers of Working Group III's contribution to the Sixth Assessment Report (AR6) as well as additional documents and information are available at https://www.ipcc. ch/report/ar6/wg3/
Note : Originally slated for publication in July 2021, the report has been delayed for months by the COVID-19 pandemic, as the work of the scientific community, including the IPCC, has moved online. This is the third time the IPCC has held a virtual endorsement session for one of its reports.
AR6 Working Group III in numbers
278 authors from 65 countries
- 36 – lead author coordinators
- 163 – lead authors
- 38 – editors
- 354 – contributing authors
More than 18,000 cited references
A total of 59,212 reviews from experts and government reviews
(Draft 1 21,703; Draft 2 32,555; Government Final Cast: 4,954)
About the IPCC
The Intergovernmental Panel on Climate Change (IPCC) is the United Nations body responsible for assessing the science related to climate change. It was established by the United Nations Environment Program (UNEP) and the World Meteorological Organization (WMO) in 1988 to provide political leaders with periodic scientific assessments of climate change, its implications and risks, as well as to propose adaptation and mitigation strategies. In the same year, the United Nations General Assembly endorsed the action of WMO and UNEP to jointly establish the IPCC. It has 195 member states.
Thousands of people around the world contribute to the work of the IPCC. For the Assessment Reports, experts volunteer their time as IPCC authors to assess the thousands of scientific papers published each year to provide a comprehensive summary of what is known about the drivers of change climate, its impacts and future risks, and how adaptation and mitigation can reduce these risks.
The IPCC has three working groups: Working Group I , which deals with the basic physical sciences of climate change; Working Group II , dealing with impacts, adaptation and vulnerability; and Working Group III , dealing with climate change mitigation. It also has a National Greenhouse Gas Inventory Working Group that develops methods to measure emissions and removals.
IPCC assessments provide governments at all levels with scientific information they can use to develop climate policies. IPCC assessments are an essential contribution to international negotiations aimed at tackling climate change. IPCC reports are written and reviewed in several stages, ensuring objectivity and transparency.
About the Sixth Evaluation Round
Full scientific assessment reports are published every 6-7 years; the latest, the Fifth Assessment Report , was completed in 2014 and provided the main scientific input to the Paris Agreement.
At its 41st session in February 2015, the IPCC decided to produce a Sixth Assessment Report (AR6). At its 42nd session in October 2015, it elected a new Bureau that would oversee the work on this report and the special reports that will be produced during the evaluation cycle. At its 43rd session in April 2016, it decided to produce three special reports, a methodological report and an AR6.
The contribution of Working Group I to the sixth assessment report On climate change 2021: the basis of the physical sciences was published on 9 August 2021. The contribution of Working group II, Climate change 2022 : impacts, adaptation and vulnerability , was published on February 28, 2022.
The final synthesis report is expected in the fall of 2022.
The IPCC also publishes special reports on more specific issues between assessment reports.
Global Warming 1.5°C , an IPCC special report on the impacts of global warming of 1.5 degrees Celsius (2.7°F) above pre-industrial levels and emission pathways greenhouse gas emissions, in the context of strengthening the global response to the threat of climate change, sustainable development and efforts to eradicate poverty was launched in October 2018.
Climate Change and Land , an IPCC special report on climate change, desertification, land degradation, sustainable land management, food security and greenhouse gas fluxes in terrestrial ecosystems was launched in August 2019, and the special report on the ocean and the cryosphere in a changing climate was published in September 2019.
In May 2019, the IPCC released the 2019 Improvement Report to the 2006 IPCC Guidelines for National Greenhouse Gas Inventories , an update of the methodology used by governments to estimate their greenhouse gas emissions and absorptions.
For more information, visit www.ipcc.ch .