IPCC: Humans to blame for climate change

A damning report released August 9 by a UN climate body IPCC finds limiting greenhouse gas emissions could help curb the impact of “human-induced global warming.”

“It is unequivocal that human influence has warmed the atmosphere, ocean and land,” the report read. “Widespread and rapid changes in the atmosphere, ocean, cryosphere and biosphere have occurred.”

Governments from around the world are enacting new climate measures to reduce emissions of the greenhouse gases behind climate change. For example, the European Commission recently unveiled its Fit for 55 legislative proposal that would apply the bloc's emissions trading system to shipping, putting pressure on shipowners to switch to cleaner fuels. And the US president Joe Biden is pursuing energy policies aimed at achieving a net-zero economy by 2050.

But some countries are still building coal-fired generation assets that could be operational well beyond 2050. Unless there is carbon capture and storage inbuilt to the design, they might emit twice as much carbon as gas-fired plants per unit of output, as well as particulates. And many countries will have to balance their books following massive public spending to mitigate the effects of the pandemic, which will make it harder to invest in order to reduce carbon emissions. 

“From a physical science perspective, limiting human-induced global warming to a specific level requires limiting cumulative CO₂ emissions, reaching at least net zero CO₂ emissions, along with strong reductions in other greenhouse gas emissions,” the IPCC said. “Strong, rapid and sustained reductions in CH₄ (methane) emissions would also limit the warming effect resulting from declining aerosol pollution and would improve air quality.”

Nevertheless, the IPCC warned that climate change is already impacting every inhabited region of the globe and it is human activity that is to blame. It is “virtually certain,” the report stated, that extreme heat and cold events are human-induced events. Each of the last four decades, meanwhile, has been warmer than the preceding decade.

Pointing to the COVID-19 pandemic, the report suggested there were temporary emissions reductions associated with the severe economic disruption brought on by the various social restrictions imposed, but the IPCC suggested those impacts were in line with natural variability. 

The UK is hosting COP26 this November in Glasgow. Among the goals is consensus on an international carbon market which will provide the financial levers needed to invest in very expensive technology such as carbon capture and storage. That forms Article 6 of the Paris Agreement of 2015. That agreement was a damp squib as signatory countries only pledged to cut their emissions under their five-yearly Nationally Determined Contributions, which form Article 4, with no consequences for failure.