From wildfires to sea level rise to heat waves, climate change is having dramatic impacts on the environment and people’s health and well-being.
What can the world do about it?
That is the focus of the third and final report – released Monday – from a recent cycle of climate discussions between scientists with the United Nations Intergovernmental Panel on Climate Change. More than 230 authors contributed to the report, which summarizes researchers’ best thinking on reducing emissions of greenhouse gases that cause climate change.
Previous reports have described the physical changes the world is undergoing due to climate change and how they are already affecting society.
In a news conference on the report’s findings, UN Secretary-General António Guterres slammed global leaders, saying the new report highlights “a litany of broken climate promises” and a catalog of “shame” that show the world is facing… Injustice is a trace.
“Government and business leaders say one thing and do another. Put simply, they lie,” he said.
Nonetheless, the latest report strikes a somewhat hopeful tone regarding the energy transition and suggests that achievable solutions are at hand.
Renewable energy costs are falling and investments in electric vehicles have provided a vision for the way forward, the scientists suggest.
“We are at a crossroads. This is the time for action. We have the tools and expertise needed to limit warming and ensure a livable future,” said IPCC Chair Hoesung Lee during the press conference announcing the report.
But the stakes have never been greater.
“Unless there are immediate and deep emission reductions in all sectors that limit warming to 1.5 degrees [Celsius] unattainable,” said Jim Skea, Professor of Sustainable Energy at Imperial College London and one of the report’s co-chairs. “Without immediate and deep emissions reductions across sectors, it will be impossible.”
Here are five key takeaways from the report’s executive summary.
The electrification of transport is a good sign
Transportation accounted for about 15 percent of global greenhouse gas emissions in 2019, and in the past it wasn’t clear how to quickly decarbonize vehicles.
But the world has come a long way since 2014, when scientists last assessed progress in cutting emissions with the IPCC.
Electric vehicle advertising has dominated Super Bowl advertising in the United States, and a global race to mine metals for clean energy is underway.
“Available technology has really changed the notion that the transportation sector … cannot reduce its emissions to zero,” said Jae Edmonds, senior scientist at Pacific Northwest National Laboratory’s Joint Global Change Research Institute and author of the IPCC report. “You see a path that could lead you there.”
Renewable energy has become cheaper in a broader sense, the report says. Since 2010, the cost of batteries and solar energy has fallen by about 85 percent. The cost of wind energy has fallen by 55 percent.
“In some cases, the cost has fallen below the cost of fossil fuels,” Skea said.
Emissions are still rising – but at a slower pace. They must peak before 2025 to limit warming to 1.5 degrees Celsius (2.7 degrees Fahrenheit).
The world is on track to increase average global temperatures by about 3.2 degrees Celsius (5.8 degrees Fahrenheit) by the end of the century compared to pre-industrial times.
World leaders pledged to reduce emissions and target 1.5 degrees Celsius during last year’s climate talks. Those ambitions are now hanging by a thread.
To meet the global 1.5 degree target, emissions must peak by 2025 and then be reduced by about 43 percent by 2030, Skea said.
Previous IPCC reports found marked differences in a world that warmed on average 1.5 degrees Celsius compared to 2 degrees. Exceeding 1.5 degrees could have irreversible effects on ecosystems. Limiting warming would save about 4 inches of average sea level rise by 2100 and halve the number of species lost more than 50 percent of their habitat.
“The longer the lag occurs, the more ambitious the reductions need to be to reach 1.5,” Edmonds said. “Eventually emissions have to go to zero.”
Oversized emissions among those at the top
Globally, the top 10 percent of households with the highest emissions per person are responsible for 34 to 45 percent of all household greenhouse gas emissions.
The bottom 50 percent of the world’s population contributes only 13-15 percent of all household emissions.
These findings align with a Stockholm Environment Institute report on carbon inequality, which found that the richest 1 percent of the world’s population is responsible as much greenhouse gas emissions as twice the pollution of the poorest 3.1 billion people.
Methane is an extremely powerful greenhouse gas that stays in the atmosphere for about 10-15 years. For researchers, reducing methane represents low-hanging fruit that could have a major impact on greenhouse gas emissions.
Capturing more methane from landfills, switching diets to include fewer livestock, and strengthening the infrastructure that transports natural gas could help reduce the impact.
“It’s a high-leverage gas, the technologies are there. You can streamline natural gas transmission and distribution systems. It’s pretty inexpensive,” Edmonds said. “When pipelines explode, the money goes into the atmosphere as a greenhouse gas, there are many incentives to tighten those systems.”
Building new fossil fuel infrastructure will not work
Continuing to install new fossil fuel infrastructure without reduction will curb greenhouse gas emissions, the report said in a summary.
Typical use of fossil fuel infrastructure already built or planned would result in exceeding the 1.5 degree target.
“Investing in new fossil fuel infrastructure is moral and economic madness,” Guterres said. Given the pace of the energy transition, investments in new fossil-fuel assets could leave those assets “stranded,” he added, meaning they would lose value before they can be financially realized.
Carbon capture and storage technologies could reduce the risk of these assets being lost, but a shift away from fossil fuels is needed, the report says.
https://www.nbcnews.com/science/environment/un-ipcc-climate-change-report-solutions-impact-rcna22011 UN report outlines possible solutions to climate change and its societal impacts