The level of carbon dioxide in the world’s atmosphere is now more than 50% higher than during the pre-industrial era, further pushing the planet into conditions not experienced for millions of years, long before the appearance of humans, shows data from the US government.
The latest measurements show the steady upward march of CO2 follows the new warning from scientists that the world may still be barred from catastrophic climate change even if global warming emissions are drastically cut, which governments have yet to achieve.
“It is depressing that we lacked the collective will to slow the steady growth of CO2Said Ralph Keeling, a geochemist who manages CO2 measurements for the Scripps Institution of Oceanography in Hawaii. “The use of fossil fuels may no longer be accelerating, but we are still racing the fastest in a global disaster.”
In May, the Mauna Loa Observatory, perched high on the slopes of a volcano on the Big Island of Hawaii, measured CO.2 concentration of 421 parts per million, only the latest escalation in an inevitable increase in CO2 due to the burning of fossil fuels and deforestation.
Before the Industrial Revolution, the Earth CO2 levels were about 280ppm for nearly 6,000 years, providing a stable basis for the progress of human civilization. Since then, however, humans have released about 1.5 trillion tons of CO2enough to warm the planet for hundreds or thousands of years to come.
This huge jump in CO2 Emissions, a hot gas that is the main engine of global warming, have rapidly pushed the world into conditions not seen in 4 million years, according to the National Oceanic and Atmospheric Administration (NOAA), which also makes measurements at Mauna Loa.
“Carbon dioxide is at levels our species has never experienced before,” said Pieter Tans, a senior scientist at Noaa’s global monitoring lab. “We’ve known about it for half a century, and we’ve failed to do anything meaningful about it. What do we need to wake up? ”
The last time CO2 levels were these high were at a time before hominids marched straight, a time called the Pliocene, about 4.1 million years ago, when concentrations reached about 400 ppm. The world back then was radically different from what we know it to be today, with Arctic forests and sea levels. five to 25 meters higher than today, which would be enough to drown many of the world’s largest cities.
The epoch-making change in our atmosphere, due to the burning of coal, oil and gas to power our cars, trucks, houses and factories, already caused severe heat waves and worsening floods, droughts and storms. These effects would be catastrophic if global warming progressed further, beyond 1.5C above the pre-industrial era, scientists say.
This limit, which the world governments agreed on in the 2015 Paris climate pact, is now more and more likely to be broken in the coming decades. A new research article found that the continued impact of past emissions means there is a 42% chance that the 1.5C limit will be exceeded even if the emissions stop immediately.
The new study, which looks at the ongoing impact of CO2 as well as methane, nitrogen oxides and aerosols, such as sulfur or soot, have found that there is a two-thirds chance of temporarily exceeding 1.5 ° C if emissions reductions remain until 2029. Scientists have said global emissions should be reduced by half. that decade. , and canceled before 2050, if the world wants to have a chance to avoid terrible climate consequences.
Despite this, emissions, which declined in 2020 as Covid-19 restrictions went into effect, rose again last year and show no sign of the steep drop needed to avoid severe effects. “Our study found that in all cases, we are committed to past emissions reaching maximum temperatures about five to 10 years before we experience them,” said Kyle Armor, a climate scientist at the University of Washington and co-author of a report.
Michelle Dvorack, a doctoral student in oceanography at the University of Washington who led the research, published in Nature Climate ChangeHe added: “Our findings are all the more urgent because we need to reduce emissions quickly.”
Bill Hare, head of Climate Analytics, said the world “He seems to be a sleepwalker to disaster. Governments seem to think that doing more is too difficult.
“What will be more difficult is dealing with a three-tier world. Already this year we have seen terrible effects, such as the heat wave in India and Pakistan, and floods in the same region. This is just the beginning. “