When locked-down city streets fell silent around the world in the first wave of the coronavirus pandemic, many people anticipated a lasting drop in greenhouse gases.
But greenhouse gas concentrations are still rising this year, after reaching a record high in 2019, the World Meteorological Organization said on Monday.
Despite lockdowns that have seen air travel plunge and kept commuters off the roads, the UN has described the drop in emissions as a “tiny blip”.
The “blip” won’t affect concentrations of the gases in our atmosphere much more than normal year-to-year fluctuations, the UN agency warned.
“The lockdown-related fall in emissions is just a tiny blip on the long-term graph. We need a sustained flattening of the curve,” said WMO secretary-general Professor Petteri Taalas.
He added: “Carbon dioxide remains in the atmosphere for centuries and in the ocean for even longer.
“The last time the Earth experienced a comparable concentration of CO2 was 3-5 million years ago.”
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The Geneva-based agency’s annual report measures the atmospheric concentration of the gases – carbon dioxide, methane and nitrous oxide – that are warming our planet.
Levels of carbon dioxide, a product of burning fossil fuels that is the biggest contributor to global warming, hit a new record of 410.5 parts per million (ppm) in 2019, the WMO said.
“We breached the global threshold of 400 ppm in 2015,” Taalas said. “And just four years later, we crossed 410 ppm.
“Such a rate of increase has never been seen in the history of our records.”
Global data is not yet available for 2020 but the trend of rising concentrations appears to be intact, the WMO said, citing initial readings from its Tasmania and Hawaii stations.
The WMO said it expects annual global carbon emissions to fall this year due to COVID measures, and ventured a preliminary estimate of between 4.2 and 7.5%.
Such a drop would not cause atmospheric carbon dioxide to go down, but would slow the rate of increase temporarily on a scale that falls within normal variations, it said.
“The COVID-19 pandemic is not a solution for climate change,” Taalas said.
“However, it does provide us with a platform for more sustained and ambitious climate action to reduce emissions to net zero through a complete transformation of our industrial, energy and transport systems.
“The needed changes are economically affordable and technically possible and would affect our everyday life only marginally.
“It is to be welcomed that a growing number of countries and companies have committed themselves to carbon neutrality. There is no time to lose.”
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