The Glasgow Climate Change Summit’s Global Stakes

In 1992, more than 150 countries agreed in Rio de Janeiro to stabilize emissions of carbon dioxide and other greenhouse gases at a level that would “prevent dangerous anthropogenic interference with the climate system” — United Nations-speak for global warming.

Many follow-up meetings have been held, long on aspiration but short on action. Emissions have gone up, as have atmospheric temperatures, while the consequences of climate change — droughts, floods, explosive wildfires in both familiar and unexpected places, melting glaciers and ice caps, dying corals, slow but inexorable sea level rise — have become ever more pronounced.

Beginning on Oct. 31, in Glasgow, the now 197 signatories to the Rio treaty will try once again to fashion an international agreement that might actually slow and then reliably (and, it is hoped, quickly) reduce emissions and thus prevent the world from tipping into full-scale catastrophe late in this century. As with other climate meetings — notably those in Kyoto in 1997, Copenhagen in 2009 and Paris in 2015 — Glasgow is being advertised as a watershed event. John Kerry, the former secretary of state who led the American negotiating team in Paris and will lead this one, called Glasgow the world’s “last best chance” to avoid ecological calamity. President Biden said he will “be there with bells on,” and 100 other world leaders are set to attend, including, of course, the host, Prime Minister Boris Johnson, but not, at least so far, President Xi Jinping of China, which is by far the world’s largest emitter of greenhouse gases.

Of all the earlier meetings, Paris was the most successful, in part because negotiators agreed to abandon years of fruitless efforts to achieve legally enforceable targets, instead eliciting modest voluntary pledges, known as nationally determined contributions, from nations large and small to do the best they could as part of a collective effort to keep the average global temperature from rising 1.5 degrees Celsius, or 2.7 degrees Fahrenheit, above preindustrial levels — just a few tenths of a degree hotter than the world is today. The 1.5 number was believed then, as it is now, to be a threshold beyond which lie warming’s most serious consequences.

That every country pledged to help inspired a lot of high-fiving among the delegates in Paris, and deservedly so. It had taken a long time to persuade both rich and poor nations that a global problem required a global solution. But the delegates were under no illusion that these pledges would be enough to reach the 1.5 degree target. So they agreed to meet again in five years in order to assess progress and ratchet up those commitments. Glasgow is that meeting.

The lack of progress since Paris invites cynicism — at the very least, wariness — about Glasgow. Atmospheric concentrations of carbon dioxide have since risen above annual averages of 400 parts per million, long seen as a dangerous threshold. In 2019 the world logged the most annual greenhouse gas emissions ever recorded, equivalent to more than 60 billion tons of carbon dioxide, a figure that includes methane and other climate-warming agents. The economic downturn caused by the Covid pandemic hardly moved the needle.

With only a week to go before the clamor begins in Glasgow, China, Australia, Russia and India have yet to make new pledges to cut their emissions. The Washington Post recently reported that Brazil and Mexico have put forward weaker targets than they submitted in Paris five years ago. Many of those that have submitted new pledges have promised rather vaguely to reach a goal of net-zero emissions by midcentury, which on paper would help keep warming within manageable limits but in practice will not do so unless followed up with real policies aimed at sharply reducing the use of fossil fuels, switching to cleaner sources of energy, electrifying cars and buildings and doing whatever else is necessary to decarbonize the world.

The question now is whether the delegates in Glasgow can rise above this pessimism and surprise us all with truly meaningful steps. Gloomy predictions to the contrary, several things have happened since Paris that should inspire everyone. For starters, the science of climate change has become tighter, tougher and more terrifying. In 2018 the Intergovernmental Panel on Climate Change issued a truly scary warning — what one U.N. official described as “a deafening, piercing smoke alarm going off in the kitchen.” The gist of it was that if the world had any hope of meeting the 1.5 degree threshold and thus avoiding ecological and social calamity, it must radically transform its energy systems not on any sort of leisurely glide path but in the next 12 years, which meant cutting greenhouse gas emissions nearly in half by 2030 and zeroing them out by 2050.

In case anyone missed the message, the I.P.C.C. repeated it in a no less alarming report in August of this year, a report that U.N. Secretary General António Guterres called a “code red for humanity.” The report warned that so much carbon dioxide had already been baked into the atmosphere that further major ecological and social damage — floods, droughts, famines, fires — was inevitable and the world should begin now to plan for it. Yet as the panel did in 2018, it opened a window of hope, arguing that with swift and sustained action to reduce the fossil fuels burned in cars, power plants and factories; vastly increase the use of renewable energy sources; and find other ways to decarbonize the planet, the world could stay within hailing distance of 1.5 degrees to avoid an even darker future.

Then, too, the delegates in Glasgow, unlike those in Paris, have lived through a year of extraordinary environmental upheaval, unprecedented in modern times. Much of it was associated with climate change — huge floods in Europe, Nigeria, Uganda and India; catastrophic wildfires in Greece, Siberia and California; fatal heat waves in the Pacific Northwest; drought and minimal snowfall that seem to be inexorably drying up rivers and reservoirs. No previous climate summit took place in similarly disturbing circumstances.

One more post-Paris development: technological progress. As the writer Fred Pearce points out in an essay on the website Yale Environment 360, the potential for achieving reductions in emissions has improved since Paris because of technological advances. Electric cars were barely on the horizon in 2015, and now one big automaker after another has pledged to produce them for mass consumption. The costs of solar and battery power have continued to go down.

Finally, and importantly, America is back in the game, after four dismal years in which President Donald Trump not only abandoned the Paris agreement but also did everything else he could think of to undermine the science of climate change and encourage the production of fossil fuels. In a complete turnabout, Mr. Biden’s ambitions match the I.P.C.C.’s demands: a 50 to 52 percent cut in emissions from 2005 levels by 2030 and net-zero emissions by 2050. Along the way, he would aim to eliminate fossil fuel emissions from power plants by 2035.

Key pieces of Mr. Biden’s climate agenda are embedded in a massive and controversial $3.5 trillion social spending bill, and one of the most important of these pieces — a carrot-and-stick program to require utilities to jettison fossil fuels in favor of noncarbon sources — is unlikely to pass. Despite grim predictions that this will undermine America’s claim to leadership on the climate issue, Mr. Kerry and his team will not go to Glasgow empty-handed. Far from it: Many other elements of the bill remain intact, including substantial tax incentives for cleaner fuels and electric cars. There are other tools in the administration’s toolbox, including proposed new mileage standards for cars and light trucks and new rules for reducing emissions of methane and the superpolluting hydrofluorocarbons used in refrigerators and air-conditioners.

In any case, America’s credibility will not be the main issue in Glasgow. The main issue there will be whether the delegates will listen to the science, look clearly at what’s happening in the world around them and then — here is the hard part — provide action plans to match their aspirations.