Carbon dioxide and other greenhouse gases trap solar radiation in the atmosphere like glass in the heat of the greenhouse. This causes temperatures to rise and causes more extreme weather, melting ice, rising sea levels and acidifying the ocean.
According to WMO, preliminary estimates suggest that global emissions would be between 4.2% and 7.5% lower this year compared to 2019. “Reducing emissions globally [of] this scale has no atmospheric effect [carbon dioxide] go down. [It] it will continue to rise, albeit at a slightly slower pace, “WMO said.
Carbon dioxide, of course, occurs in the atmosphere – without it, the Earth would be too cold to sustain life. It circulates in and out of the atmosphere, keeping the system in balance. The problem is that human activities – especially the burning of fossil fuels – have injected much more carbon dioxide into the system, much more than can be absorbed. According to the WMO, the reduction caused by the closure of man-made emissions is smaller or at most similar in size to natural fluctuations, so it will not make a difference in the long run.
It’s a bit like filling a tub. As long as the water flows a little slower this year, the bathtub will continue to fill until more water flows than it drains.
The amount of carbon dioxide in the atmosphere fluctuates, of course – but for much, much longer than it does now. By studying air bubbles trapped deep in ice cores, scientists know that until humans started burning fossil fuels about 300 years ago, carbon dioxide levels would not have exceeded 300 million parts per million about a million years ago. According to the WMO, the amount of carbon dioxide in the atmosphere is now nearly 50% higher than in 1750.
“Carbon dioxide will remain in the atmosphere for centuries and in the ocean for even longer,” said Professor Petteri Taalas, WMO Secretary-General in a statement. “The Earth last experienced a similar concentration [carbon dioxide] It was 3-5 million years ago when the temperature was 2-3 ° C warmer and the sea level was 10-20 meters higher than now. But it had no population of 7.7 billion. “
Methane, a less common but more powerful greenhouse gas, has also risen in the past year. Its concentration in the atmosphere is now more than 2.5 times the pre-industrial revolution level. About 60% of the methane released into the atmosphere comes from human activities – mainly agriculture, fossil fuel exploitation, landfills and biomass combustion.