According to a new study, global glasshouse gas emissions have risen to an all-time high amid an unmatched pace of global warming.
50 leading scientists cautioned on Thursday in a comprehensive update on climate research that from 2013 through 2022, “human-induced warming has been increasing at an unprecedented rate of more than 0.2 degrees Celsius per decade.”
In a peer-reviewed paper intended at policymakers, they claimed that average yearly emissions over the same period reached an all-time high of 54 billion tonnes of CO2 or its equivalent in other gases – over 1,700 tonnes every second.
At the crucial COP28 climate summit later this year in Dubai, where a “Global Stocktake” at the United Nations negotiations will evaluate progress towards the 2015 Paris Agreement’s temperature goals, world leaders will be presented with the new data.
The findings would seem to rule out limiting global warming under the Paris Treaty’s more aggressive 1.5C target, which has long been regarded as a safety nett for a world that is generally climate-safe, although still being rocked by severe consequences.
“Even though we are not yet at 1.5C warming, the carbon budget” – the amount of greenhouse gases humanity can emit without exceeding that limit – “will likely be exhausted in only a few years,” said lead author Piers Forster, a physics professor at the University of Leeds.
According to Forster and colleagues, many of whom were core IPCC contributors, that budget has decreased by half since the Intergovernmental Panel on Climate Change (IPCC), the UN organisation that advises on climate science, gathered information for its most recent benchmark report in 2021.
They concluded that emissions of carbon dioxide, methane, and other warming agents, which are primarily produced by burning fossil fuels, must not surpass 250 billion tonnes (gigatonnes) in order to have even a coin-toss chance of staying below the 1.5C threshold.
The carbon budget would be reduced to only 150Gt or 100Gt, respectively, a two- or three-year lifeline at the current rate of emissions, depending on whether the odds were improved to two-thirds or four-fifths.
According to the IPCC, in order to maintain the Paris temperature targets, CO2 emissions must be reduced by at least 40% by 2030 and completely eliminated by the middle of the century.
The new data show that, ironically, one of the major climate success stories of the past ten years has unintentionally accelerated the rate of global warming.
The usage of coal, which emits substantially more carbon dioxide per unit of energy than either oil or gas, has steadily decreased. However, it has also lessened air pollution, which protects Earth from the Sun’s rays at their full intensity.
Particle pollution from all causes reduces warming by around half a degree Celsius, so as the air gets cleaner, more heat will be able to reach the planet’s surface, at least temporarily.
The new analysis, the first in a series of periodic evaluations that will help bridge the gaps between IPCC reports, which have been published on average every six years since 1988, was published in the peer-reviewed journal Earth System Science Data.
“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 change crisis at the top of the agenda,” said co-author and scientist Maisa Rojas Corradi, who is also the environment minister of Chile.
Even if there is indication that the increase in glasshouse gases has slowed, co-author Valerie Masson-Delmotte, a co-chair of the 2021 IPCC assessment, said the new data should be a “wake-up call” before the COP28 session.
“The pace and scale of climate action is not sufficient to limit the escalation of climate-related risks,” the speaker claimed.
Since 2000, researchers have also documented a remarkable increase in temperature throughout land areas, excluding seas.
“Land average annual maximum temperatures have warmed by more than half a degree Celsius in the last ten years (1.72C above preindustrial conditions) compared to the first decade of the millennium (1.22C),” the study found.
Large swaths of South and South-east Asia, as well as regions straddling the equator in Africa and Latin America, could face a life-and-death threat in the coming decades from longer and more powerful heat waves, according to recent studies.
