COVID-19 could cause greatest slump in CO2 emissions since WW2

The World Meteorological Organization (WMO) has predicted a 6 percent drop in carbon dioxide emissions in 2020 as a result of the coronavirus health emergency—the largest dip in any single year since World War II.

However, the decline in emissions is expected to be brief and the WMO says it is likely to be followed by a surge in emissions in 2021.

"In the most likely case we will easily go back to normal next year and there might even be a boost in emissions because some industries have been stopped," WMO Secretary-General Petteri Taalas said at a virtual briefing on Wednesday, Reuters reports.

Even a 6 percent decline is not enough to meet United Nations' guidelines. According to the U.N. Environment Programme's annual Emissions Gap Report in 2019, a 7.6 percent reduction in global greenhouse gas emissions is needed each year between now and 2030 if the planet is to meet targets set out in the Paris Agreement.

"Our collective failure to act early and hard on climate change means we now must deliver deep cuts to emissions," Inger Andersen, UNEP's Executive Director, said in a statement at the time.

Taalas said the the health emergency has place additional burden on communities already threatened by climate change.

"Extreme weather has increased, and it will not go away because of the coronavirus," he said. "On the contrary, the pandemic exacerbates the challenge of evacuating people and keeping them safe from tropical cyclones, as we saw with Category-5 strength Harold in the South Pacific."

The announcements were made on the 50th Earth Day, an annual event intended to build support and awareness for the environment. Fifty years years ago—when Earth Day was launched—the average global temperature was 0.24 degrees Celsius above the pre-industrial era, WMO reports.

Today, the average global temperature has risen 1.1C above the pre-industrial era. Carbon dioxide levels measured at global observing stations are approximately 26 percent higher than they were in 1970.

To mark Earth Day, the WMO has published its Global Climate report, confirming 2015-2019 were the warmest five-year period on record. The late 2010s also saw a spike in carbon dioxide levels—according to the report, CO2 growth rates were 18 percent higher in 2015-2019 than they were in the preceding five years.

The greenhouse gas lingers in the Earth's atmosphere and oceans for centuries, which means the world will see more extreme effects of climate change even if emissions flatline overnight, the WMO said.

"Whilst COVID-19 has caused a severe international health and economic crisis, failure to tackle climate change may threaten human well-being, ecosystems and economies for centuries," said Taalas. "We need to flatten both the pandemic and climate change curves."

The WMO calls for a stimulus package to help the global economy grow once the COVID-19 crisis is over, citing past economic crises, which were followed by jumps in CO2 emissions.

"We need to show the same determination and unity against climate change as against COVID-19," said Taalas. "We need to act together in the interests of the health and welfare of humanity not just for the coming weeks and months, but for many generations ahead."

Earth Day event against climate change at Gwanghwamun square
Members of the Asian Citizen's Center for Environment and Health, wearing masks depicting the COVID-19 coronavirus, perform during an Earth Day event against climate change at Gwanghwamun square in Seoul on April 22, 2020. Experts at the World Meteorological Organization predict a 6 percent drop in CO2 emissions related to the global health emergency. Jung Yeon-je / AFP/Getty