Dr Keeling noted that last year’s decline in annual emissions was too small to be detected in atmospheric data, as it can be eclipsed by natural fluctuations in carbon emissions from vegetation and soil in response to changes. seasonal soil temperature and humidity. Scripps scientists previously estimated that humanity’s emissions would need to fall by 20 to 30 percent for at least six months to cause a noticeable slowdown in the rate of increase of carbon dioxide in the atmosphere.
And, according to scientists, there is only one way to prevent the total amount of carbon dioxide in the atmosphere from continuing to rise: Nations should essentially reduce their net annual emissions to zero, mostly by passing. from fossil fuels to cleaner technologies that do not emit carbon dioxide, such as electric cars powered by wind, solar or nuclear power.
Last month, the International Energy Agency released a detailed roadmap on how all countries around the world could achieve net zero emissions by 2050. The changes would be drastic, the agency found: countries are set to stop building new coal-fired power plants immediately, ban the sale of gasoline vehicles by 2035, and install wind turbines and solar panels at an unprecedented rate.
If countries succeed in meeting this target, they could limit total global warming to around 1.5 degrees Celsius, compared to pre-industrial levels. (The Earth has already warmed by more than a degree Celsius since pre-industrial times.) This could help humanity avoid some of the worst impacts of climate change, such as the irreversible collapse of polar ice caps or the widespread poor harvests.
But so far, the agency warned, the world is not on track to meet that goal. Total annual emissions are currently expected to increase at their second fastest rate this year, as countries recover from the pandemic and global coal combustion nears all-time highs, driven by increased industrial activity in Asia.
The amount of carbon dioxide in the atmosphere currently varies by about 10 parts per million over the course of a year. It peaks every year in May, before seasonal vegetation growth in the northern hemisphere, which makes up about two-thirds of Earth’s land mass, removes some of the gas through photosynthesis.
May’s average first surpassed 400 parts per million in 2014, a milestone that attracted global media coverage. Since then, emissions have continued to skyrocket. The latest annual average, for 2019, was 409.8 parts per million, about 46% above the pre-industrial average of 280.