I might have missed Earth Day, but I haven’t missed the point: every day is Earth Day, or at least it should be. April 22 has been officially celebrated as Earth Day every year since 1970, “one of the most remarkable happenings in the history of democracy,” proclaimed American Heritage Magazine. Furthermore, unless the leaders of the world’s industrialized countries change their policies, unless the citizens of these countries change their habits, warn many scientists, the earth will be permanently damaged, if not become totally uninhabitable.

The theme for Earth Day 2020 is climate action, the issue designated as the most pressing topic for the 50th anniversary.

The founder of Earth Day was a politician, U.S. Sen. Gaylord Nelson, who convinced President John F. Kennedy to go on a national conservation tour in 1962. That same year an environmental science book was published, “Silent Spring” by Rachel Carson. The book’s title referred to a spring when no birds would be heard singing.

This landmark book documented the adverse environmental effects caused by the indiscriminate use of pesticides. A presidential commission confirmed the claims of Carson, who wrote:

“It is not my contention that chemical insecticides must never be used. I do contend that we have put poisonous and biologically potent chemicals indiscriminately into the hands of persons largely or wholly ignorant of their potentials for harm. We have subjected enormous numbers of people to contact with these poisons, without their consent and often without their knowledge.”

Despite being met with fierce opposition by chemical companies, thanks to public opinion, the book brought about numerous changes: a reversal in the United States’ national pesticide policy, a nationwide ban on DDT for agricultural uses and the start of an environmental movement that led to the creation of the U.S. Environmental Protection Agency.

Another book, “An Inconvenient Truth,” written by former Vice President Al Gore and published in 2006, renewed the campaign to educate people about global warming and reenergized the environmental movement. The documentary film based on Gore’s book has been shown to audiences worldwide and also been included in science curricula in schools around the world, which has spurred some controversy. A sequel to the film, titled “An Inconvenient Sequel: Truth to Power,” was released in 2017.

Greta Thunberg is a 15-year-old Swedish environmental activist who has gained international recognition for promoting the view that humanity is facing an existential crisis arising from climate change. Thunberg is known for her youth and her straightforward speaking manner, both in public and to political leaders and assemblies, in which she criticizes world leaders for their failure to take sufficient action to address the climate crisis.

Not all world leaders are guilty, however. In December 2015 in Paris, parties reached a landmark agreement to combat climate change and to accelerate and intensify the actions and investments needed for a sustainable low carbon future. The Paris Agreement brings all nations into a common cause to undertake ambitious efforts to combat climate change and adapt to its effects, with enhanced support to assist developing countries. It charts a new course in the global climate effort.

The Paris Agreement’s central aim is to strengthen the global response to the threat of climate change by reducing a global temperature rise this century. Additionally, the agreement aims at increasing the ability of countries to deal with the impacts of climate change and to make them more climate-resilient.

Americans must take the lead in this effort because our 5% of the world’s population consumes 25% of the world’s energy. What Rachel Carson wrote over 50 years ago is still true today: “We in this generation must come to terms with nature; we are challenged as never before to prove our maturity and our mastery, not of nature but of ourselves.”

Jim Izzo lives in Mystic.

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