How to make it to Earth Day 2070

The 50th anniversary of the first Earth Day on Wednesday is a chance to look back at environmental progress — and forward to the enormous challenges that remain.

The big picture: By many measures, the air and water in the U.S. is far cleaner than it was in 1970, thanks in no small part to the activism that helped create Earth Day. But the next 50 years will require leaps of innovation to address climate change.

The state of play: Perhaps the most significant indicator of just how far behind we're falling on climate change is something that, on the surface, would seem like a positive: the drastic drop in carbon emissions due to COVID-19 lockdown policies.

• According to research firm Carbon Brief, global carbon emissions could fall by around 2 billion metric tons this year, equivalent to 5.5% of last year's record emissions. That would represent the biggest drop since World War II.
• Yet UN projections say holding global temperature rise below 1.5°C would require even greater annual emission reductions of 7.6% over the next decade.
• "If this is all we get from shutting the entire world down, it illustrates the scope and scale of the climate challenge, which is fundamentally changing the way we make and use energy and products," Costa Samaras, a climate scientist at Carnegie Mellon University, told E&E News.

My thought bubble: The COVID-19 experience is giving us an object lesson in what happens when the growth that drives the global economy halts and goes in reverse. It is not pleasant, and it's not an experience most of the world would choose to undergo voluntarily, even to save the climate.

• What this means is that our best chance to ensure the 100th Earth Day is better than the 50th Earth Day is going to be through innovations that allow growth to continue without adding to the burden of climate change.
• Regulations and global treaties like the Paris Climate Agreement will surely play a role, just as laws like the Clean Air Act helped drastically reducing air pollution. But carbon, unlike other pollutants, is so central to human activity that dislodging it can't be accomplished solely by legislative fiat — even if there were the political will to do so.

What they're saying: "What we're experiencing today is a warning of things to come," says Clinton Moloney, managing director of sustainability solutions at ENGIE Impact. "Companies need to reconfigure their business models to continue to grow while decoupling from resource consumption and delivering on the Paris Climate Agreement."

Flashback: In 1970, the threat of climate change had barely scratched public consciousness. But it was impossible to ignore just how filthy and unhealthy America's environment had become.

• Cities treated rivers as little more than sewers, culminating in Cleveland's heavily polluted Cuyahoga River literally catching fire in 1969.
• Air quality around major cities was just as bad, resulting in smog and other forms of air pollution that posed a direct and visible threat to human health.

The environmental movement that launched the first Earth Day was massive — by some estimates, a tenth of the U.S. population participated in events that day — and it helped spur the bipartisan passage of major legislation, which in turn led to visibly cleaner water and air today. But those same decades saw the rise of climate change as a global threat — and we've been nowhere near as successful in addressing it.

• The average atmospheric concentration of CO2 — the single factor that most directly drives global warming — has risen from 325 ppm on the first Earth Day to 410 ppm now.
• Average global surface temperatures have risen by nearly 1°C (1.8°F) since 1970.
• Annual global carbon emissions have more than doubled since the first Earth Day, and they hit an all-time high last year.

The bottom line: The first 50 Earth Days added up to a mixed environmental success, but the next 50 will be far tougher.