FROM 2010 to 2019 , average global greenhouse gas emissions were at their highest levels in human history , but the growth rate has slowed . Without immediate and deep emissions reductions across all sectors , limiting global warming to 1.5 ° C is beyond reach .
However , scientists in the latest Intergovernmental Panel on Climate Change ( IPCC ) report released recently showed increasing evidence of climate action .
Since 2010 , there have been sustained decreases of up to 85 per cent in the costs of solar and wind energy and batteries . An increasing range of policies and laws have enhanced energy efficiency , reduced deforestation rates , and accelerated the deployment of renewable energy .
“ 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 ,” said IPCC Chair Lee Hoe-sung .
“ I am encouraged by climate action being taken in many countries . There are policies , regulations and market instruments that are proving effective . If these are scaled up and applied more widely and equitably , they can support deep emissions reductions and stimulate innovation .”
The Summary for Policymakers of the IPCC Working Group III report , Climate Change 2022 : Mitigation of climate change , was approved on Apr 4 2022 , by 195 member governments of the IPCC , through a virtual approval session that started on Mar 21 . It is the third instalment of the IPCC ’ s Sixth Assessment Report ( AR6 ), which will be completed this year .
Options in all sectors to at least halve emissions by 2030
Limiting global warming will require significant transitions in the energy sector . This will involve a substantial reduction in fossil fuel use , widespread electrification , improved energy efficiency , and alternative fuels ( such as hydrogen ).
“ Having the right policies , infrastructure , and technology to enable changes to our lifestyles and behaviour can result in a 40-70 per cent 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 .”
Cities and other urban areas also offer significant opportunities for emissions reductions . These can be achieved through lower energy consumption ( such as by creating compact , walkable cities ), electrification of transport in combination with low-emission energy sources , and enhanced carbon uptake and 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 all climates ,” said IPCC Working Group III Co-Chair Jim Skea . “ Action in this decade is critical to capture the mitigation potential of buildings .”
Reducing emissions in the industry will involve using materials more efficiently , reusing and recycling products and minimising waste . Low- to zero-greenhouse gas production processes are at their pilot to the near-commercial stage for basic materials , including steel , building materials and chemicals .
This sector accounts for about a quarter of global emissions . Achieving net-zero will be challenging and require new production processes , low and zero-emissions electricity , hydrogen , and , where necessary , carbon capture and storage .
Agriculture , forestry , and other land use can provide large-scale emissions reductions and also remove and store carbon dioxide at scale . However , land cannot compensate for delayed emissions reductions in other sectors .
Response options can benefit biodiversity , help us adapt to climate change , and secure livelihoods , food and water , and wood supplies .
The next few years are critical
In the scenarios assessed , limiting warming to around 1.5 ° C ( 2.7 ° F ) requires global greenhouse gas emissions to peak before 2025 . It should be reduced by 43 per cent 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 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 ),” said Skea . “ Without immediate and deep emissions reductions across all sectors , it will be impossible .”
Agriculture , forestry , and other land use can provide large-scale emissions reductions and also remove and store carbon dioxide at scale . However , land cannot compensate for delayed emissions reductions in other sectors .”
The global temperature will stabilise when carbon dioxide emissions reach net zero . For 1.5 ° C ( 2.7 ° F ), this means achieving net-zero carbon dioxide emissions globally in the early 2050s ; for 2 ° C ( 3.6 ° F ), it is 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 before 2025 at the latest and be reduced by a quarter by 2030 .
Closing investment gaps
The report looks beyond technologies and demonstrates that while financial flows are three to six times lower than 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 more substantial public sector finance and policy alignment .
“ 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 . This is provided we take the actions necessary to limit warming to 2 ° C ( 3.6 ° F ) or below , compared to maintaining current policies ,” said Shukla .
Achieving the Sustainable Development Goals
Accelerated and equitable climate action in mitigating and adapting to climate change impacts is critical to sustainable development . Some response options can absorb and store carbon and , at the same time , help communities limit the effects 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 employment and business opportunities . Electrification with renewables and shifts in public transport can enhance health , employment , and equity .
“ Climate change results from more than a century of unsustainable energy and land use , lifestyles and patterns of consumption and production ,” said Skea . “ This report shows how taking action can move us towards a fairer , more sustainable world .” — @ Green