‘This Is the Critical Decade for Climate Change’: Global Greenhouse Gas Emissions Reach Record High

A new study by 50 leading scientists conducted to supplement the “information gap” between Intergovernmental Panel on Climate Change (IPCC) reports said global greenhouse gas emissions have soared to a record high and are threatening to push our planet into “unprecedented” global heating.

Earth’s carbon budget — the amount of carbon dioxide that can be emitted to have a greater than 50 percent likelihood of keeping global warming to 1.5 degrees Celsius — is quickly running out, the study warned.

“Evidence-based decision-making needs to be informed by up-to-date and timely information on key indicators of the state of the climate system and of the human influence on the global climate system. However, successive IPCC reports are published at intervals of 5–10 years, creating potential for an information gap between report cycles,” the authors of the study wrote.

According to the researchers, since the last major climate system assessment published two years ago, human-caused global warming has kept increasing at an “unprecedented rate,” a press release from the University of Leeds said.

The study, “Indicators of Global Climate Change 2022: annual update of large-scale indicators of the state of the climate system and human influence,” was published in the journal Earth System Science Data.

The researchers found that human activity caused the equivalent of an average of 54 gigatonnes of carbon dioxide to be released into the atmosphere each year from 2012 to 2021.

“This is the critical decade for climate change. Decisions made now will have an impact on how much temperatures will rise and the degree and severity of impacts we will see as a result,” said professor Piers Forster, lead author of the paper and director of the Priestley Centre for Climate Futures at the University of Leeds, in the press release.

The “timely wake-up call,” as one of the researchers called the study, comes as preparations are being made for the COP28 climate conference in December.

“This robust update shows intensifying heating of our climate driven by human activities. It is a timely wake up call for the 2023 global stocktake of the Paris Agreement — the pace and scale of climate action is not sufficient to limit the escalation of climate-related risks,” said Dr. Valérie Masson-Delmotte, a researcher from the Université Paris Saclay who co-chaired Working Group 1 of the IPCC’s Sixth Assessment report and was involved in the climate indicators project, in the press release.

Because the global climate system is changing so quickly, the scientists say climate negotiators, policymakers and civil society groups must have access to the latest scientific evidence to inform their decision making.

In a university-led initiative, an open data and science platform — the Indicators of Global Climate Change — has been developed by the researchers. The platform’s website will provide yearly updates on key climate indicators.

“Long-term warming rates are currently at a long-term high, caused by highest-ever levels of greenhouse gas emissions. But there is evidence that the rate of increase in greenhouse gas emissions has slowed,” Forster said in the press release. “We need to be nimble footed in the face of climate change. We need to change policy and approaches in the light of the latest evidence about the state of the climate system. Time is no longer on our side. Access to up-to-date information is vitally important.”

The researchers shared how key climate indicators have changed since the 2021 publication of the IPCC’s Sixth Assessment Working Group 1 report, which contained the essential data for the IPCC Sixth Synthesis Report.

The average 1.14 degrees Celsius increase from 2013 to 2022 was up from the average of 1.07 degrees Celsius from 2010 to 2019, and human-induced warming has reached a rate of increase of more than 0.2 degrees Celsius per decade, the scientists said.

“An annual update of key indicators of global change is critical in helping the international community and countries to keep the urgency of addressing the climate crisis at the top of the agenda and for evidence-based decision-making,” said profesor Maisa Rojas Corradi, who is a Minister of the Environment in Chile, an IPCC author and a scientist involved in the study, in the press release. “In the case of Chile, we have a climate change law that aims at aligning government-wide policies with climate action.” 

A key finding of the study was that the carbon budget has been dwindling at an increased rate. In 2020, the remaining carbon budget was calculated by the IPCC to be around 500 gigatonnes, but by 2023, it was about half that amount.

“Even though we are not yet at 1.5°C warming, the carbon budget will likely be exhausted in only a few years as we have a triple whammy of heating from very high CO2 emissions, heating from increases in other GHG emissions and heating from reductions in pollution,” Forster said in the press release.

Each incremental increase in global warming causes climate extremes, like droughts, heat waves and heavy rainfall, to increase in intensity and frequency.

“If we don’t want to see the 1.5°C goal disappearing in our rearview mirror, the world must work much harder and urgently at bringing emissions down,” Forster said.