The history of Earth Day began in Santa Barbara in early 1969, when an oil platform six miles offshore of the idyllic beach town on the central coast of California blew out, spewing some 100,000 barrels of crude into the Pacific. It was the largest oil spill in US history at the time (today it is the third-largest), and catalyzed the modern environmental movement.
Over the next year, Gaylord Nelson, a US senator from Wisconsin, marshaled the personnel, resources, and political capital to create what the politician called a “national teach-in on the environment.” The first Earth Day was held on April 1970, and its impact on public education and policy was tremendous. Millions of Americans took to the streets to demand environmental improvements and, according to Earth Day Network, “by the end of that year, the first Earth Day had led to the creation of the United States Environmental Protection Agency and the passage of the Clean Air, Clean Water, and Endangered Species acts.” Those laws remain the bedrock of environmental regulation today.
Perhaps more important was the effort that began in 1990 to bring Earth Day to the entire Earth, and to start honing its focus towards the Earth’s biggest impending challenge: climate change.
It was a success. After averaging just 38 media mentions a year from 1970 to 1989, “Earth Day” was referenced over 5,550 times by the press on its 20th anniversary in 1990.
From 1970 until 1990, the media mentioned “climate change” just 157 times on average every year; from 1970 to 1975, the phrase was used just five times in total, four by the New York Times and once by PBS.
In the decade after 1990, when Earth Day went global, annual media mentions of “climate change” shot up to nearly 5,750. The biggest increases occurred after 1997, when the Kyoto Protocol was signed.
Then, in 2007, the UN’s Intergovernmental Panel on Climate Change put out its fourth assessment report (pdf). It was the strongest statement yet about where the world was headed. “Warming of the climate system is unequivocal,” the report said, adding in clear terms that “most of the observed increase in global average temperatures since the mid-20th century is very likely due to the observed increase in anthropogenic greenhouse gas concentrations.”
After that, climate change became a household term. Media references to “climate change” have so far outstripped those to “Earth Day” that the chart for 2001-2017 required an entirely different scale than that for 1970-2000:
And in general, interest in Earth Day seems to have reached its peak, and may now be tapering off.
This is largely a sign of Earth Day’s success. Earth Day 1990 was influential in kickstarting the global conversation on climate change, and setting the stage for the 1992 Earth Summit held in Rio de Janeiro, Brazil, where the United Nations Framework Convention on Climate Change was signed. The UNFCCC is the underlying structure on which the Paris Agreement is built, and the driving force behind the IPCC reports.
Public interest in Earth Day may have flatlined, but today, the issues it campaigns for, from climate change mitigation and reforestation to ending plastic pollution and supporting women in environmental leadership positions, have pervaded global discourse. Meanwhile, trends like wind and solar development in the US, and global investment into renewable energy, to name two examples, closely track with how pervasive discussion of climate change and environmental protection has become.
In other words, as science reporter Akshat Rathi wrote in this weekend’s edition of the Quartz Daily Brief newsletter:
…all signs suggest the scale of the environmental movement has crossed a tipping point. It’s no longer just the woman on the street who seeks environmental justice. Instead, the movement now includes wealthy investors and powerful governments. In the past year alone, activist shareholders, including trillion-dollar investors like BlackRock and Vanguard, have forced fossil-fuel companies like ExxonMobil and Occidental Petroleum to reveal the risks to their investments from climate change. In the face of Donald Trump’s retreat from the Paris climate accords, local governments have become stewards of the environment….
There is good news from other corners, too. Government investment and regulations in developing and deploying clean energy have scaled well. In many parts of the world, it is cheaper to build renewable-energy projects than fossil-fuel power plants. This week, the UK went 55 hours without burning coal, which hasn’t happened since before the Industrial Revolution. Portugal produced more renewable energyin March than energy it consumed.
That said, much more must be done, and rapidly, in order to avoid the global temperature increases that scientists agree are likely to cause cataclysmic changes to the Earth’s climate. Every 10 years, interest in Earth Day spikes on its decennial anniversaries. The organizers of the movement hope to use the 2020 anniversary—Earth Day’s 50th—as a means to propel global climate-change mitigation towards a pace where we might save life on Earth as we know it. Because even the most generous of predictions suggest we need to reach zero emissions in the next 40 years—that is, if we want to be around to celebrate Earth Day’s 100th anniversary in 2070.