Tony Barboza, Tribune News Service

The global struggle to slow the spread of the coronavirus has brought with it cancelled flights, closed businesses and a quickly escalating economic slowdown that could be devastating to millions. It is also certain to shrink greenhouse gas emissions this year, according to climate scientists.

But does that mean we are turning a corner in cutting planet-warming pollution?

If history is any indication, no. The slide in emissions will be temporary, experts say. What’s more, scientists and environmentalists worry the pandemic will at the same time undermine government and industry’s resolve to cut emissions in the long term.

Experts are predicting the health crisis will cause global emissions to drop for the first time since 2009, during the Great Recession. But a look back over the decades shows a steady rise in greenhouse gases punctuated by temporary dips caused by economic downturns, including the 2008 global financial crisis and the oil shocks of the 1970s. Pollution bounces back predictably once the economy starts improving again, with the resurgence in industrial activity, travel and consumption more than offsetting any short-lived benefits to the climate.

“I won’t be celebrating if emissions go down because of the coronavirus,” said Rob Jackson, an environmental scientist at Stanford University who chairs the Global Carbon Project. “We need sustained declines. Not an anomalous year below average.”

Global greenhouse gas emissions rose only slightly in 2019, Jackson said, so it wouldn’t take a big economic shock to push them downward. NASA and European Space Agency satellites have detected big drops in air pollution concentrations in China and Italy as millions went under lockdown or quarantine to slow the virus.

At the same time, there are already some indications industry and regulators want to put the brakes on climate action. Airlines that only months ago were touting efforts to go carbon-neutral to address their rapidly rising emissions are now hit so hard by the slowdown they are warning they will run out of cash without billions in government aid. In Europe, now the epicenter of the pandemic, some airline companies have pushed regulators to delay emissions-cutting policies on account of the coronavirus. The Czech Republic’s prime minister urged the European Union to abandon a landmark law seeking net zero carbon emissions to focus instead on battling the outbreak.

“I’m concerned about a sustained downturn in the economy and the narrative that we no longer have the luxury of addressing emissions,” Jackson said. “That would be devastating.”

Los Angeles and Long Beach officials, meanwhile, cited the virus-related hit to cargo volumes at the nation’s largest seaport as one reason for voting to approve only a modest clean-air fee on shipping containers earlier this month. Air quality officials said the $20-per-container fee is too low to make adequate progress cutting greenhouse gas emissions from thousands of diesel trucks that move goods through a complex that comprises Southern California’s largest single source of air pollution.

Alex Comisar, a spokesman for L.A. Mayor Eric Garcetti, said the city-owned port is “not backing down on our environmental goals.”

“Tariffs have a very real impact on our port, and COVID-19 does add another level of uncertainty that we are already beginning to feel,” Comisar said, adding that officials will revisit the fee annually “to closely monitor its economic and environmental impacts, and ensure no ground is lost in the fight against climate change.”

Some environmentalists are optimistic that social distancing measures being adopted to slow the coronavirus, including a sudden shift to working from home and drastic reductions in air travel, could permanently change people’s attitudes about the transformations needed to slow climate change.

Well before the virus emerged, there was a growing “fight-shaming” movement and a trend among environmentalists and scientists to reduce their carbon footprint by forgoing travel in favour of virtual meetings and videoconferencing.

There is precedent for environmental concerns being pushed aside during times of crisis, only to be followed by a resurgence in pollution as the economy recovers, as was the case after the 2008 global financial crisis.

“After a decrease, you saw carbon dioxide emissions from fossil fuel and cement bounce back in a major, major way in 2010,” said Kelly Levin, a senior associate in the climate program at the World Resources Institute, who worries about the world following a similar trajectory as leaders take urgent, short-term measures to stimulate the economy.

“I think there’s a huge risk that we could boost activity in traditionally heavy industries,” Levin said, though it doesn’t have to be that way. Economic downturns sometimes push in both directions simultaneously, with businesses and governments responding with some economy-boosting measures that hurt the environment and others that promote conservation. That’s what happened with the oil crises of the 1970s.