In order to limit global warming to around 1.5°C, greenhouse gas emissions need to reach their highest peak before 2025, and by 2030, greenhouse gas emissions must be reduced by 43%, according to the Intergovernmental Panel on Climate Change (IPCC) 6th Assessment Report, which was authored by 278 scientists and experts. (Three minute video report here.)
While during 2010-2019, the average annual global greenhouse gas emissions were at their highest levels in human history, the rate of growth has slowed. IPCC scientists also said that there is increasing evidence of climate action. There are policies, regulations and market instruments that are proving effective.
Since 2010, there have been sustained decreases of up to 85% in the costs 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 preliminary patter is very supportive, but it's a bit like that work or school counselling meeting. It's simply saying that while we clearly have the capability, we are still behaving badly and need to put our skills for good to work. Those policies, regulations and market instruments that are proving effective need to be scaled up and applied more widely and equitably to support deep emissions reductions and stimulate innovation. Without immediate and deep emissions reductions across all sectors, limiting global warming to 1.5°C is beyond reach.
Use of fossil fuels are the clearest way to reducing emissions. Limiting global warming will require major transitions in the energy sector. This will involve a substantial reduction in fossil fuel use, widespread electrification, improved energy efficiency, and use of alternative fuels (such as green hydrogen, wind and solar).
There are options for established, rapidly growing and new cities.The price of renewable energy and batteries for passenger electric vehicles has fallen significantly, and their adoption continues to rise.
Reducing emissions in industry will involve using materials more efficiently, reusing and recycling products and minimising waste. For basic materials, including steel, building materials and chemicals, low- to zero-greenhouse gas production processes are at their pilot to near-commercial stage.This sector accounts for about a quarter of global emissions. Achieving net zero will be challenging and will 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.
One of the great unsung benefits of mitigating climate change is that having the right policies, infrastructure and technology in place to enable changes to our lifestyles and behaviour can result in a 40-70% reduction in greenhouse gas emissions by 2050. 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.
The report looks beyond technologies and demonstrates that while financial flows are a factor of three to six times lower than levels needed by 2030 to limit warming to below 2°C, 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.
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 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 employment and business opportunities. Electrification with renewables and shifts in public transport can enhance health, employment, and equity. IPCC Working Group III Co-Chair Jim Skea:
“CLIMATE CHANGE IS THE RESULT OF MORE THAN A CENTURY OF UNSUSTAINABLE ENERGY AND LAND USE, LIFESTYLES AND PATTERNS OF CONSUMPTION AND PRODUCTION. THIS REPORT SHOWS HOW TAKING ACTION NOW CAN MOVE US TOWARDS A FAIRER, MORE SUSTAINABLE WORLD.”
While the growth rate of emissions was slower between 2010 and 2019 than between 2000 and 2009, human generated emissions are still increasing and we aren't even meeting the COP26 climate pledges. According to UN Chief, Guterres, most major emitters are not taking the steps needed to fulfill even the inadequate promises made at COP26, which means that globally current climate policy responses are not sufficient to reduce greenhouse gas emissions, let alone enough to limit global warming to around 1.5° Celsius. UN Secretary General António Guterres:
“WE ARE ON A FAST TRACK TO CLIMATE DISASTER: MAJOR CITIES UNDER WATER. UNPRECEDENTED HEATWAVES. TERRIFYING STORMS. WIDESPREAD WATER SHORTAGES. THE EXTINCTION OF A MILLION SPECIES OF PLANTS AND ANIMALS. THIS IS NOT FICTION OR EXAGGERATION. IT IS WHAT SCIENCE TELLS US WILL RESULT FROM OUR CURRENT ENERGY POLICIES.”
In the scenarios the report scientists assessed, limiting warming to around 1.5°C 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 below it by the end of the century.
The global temperature will stabilise when carbon dioxide emissions reach net zero. For 1.5°C, this means achieving net zero carbon dioxide emissions globally in the early 2050s; for 2°C it is in the early 2070s. This assessment shows that limiting warming to around 2°C still requires global greenhouse gas emissions to peak before 2025 at the latest, and be reduced by a quarter by 2030.
Images and Graphs in order from top: Chris Leboutillier, Unsplash | IPCC | Nicholas Doherty, Unsplash | IPCC | Reuters | Press Release IPCC Report