Happy Earth Day, Climatific!

Welcome back to Climatific, a free, weekly read that breaks down climate science so it makes sense- not for scientists or researchers, but for everyday people trying to understand the planet we live on, what’s happening to it, and why it matters.

Tomorrow—Wednesday, April 22nd—is Earth Day 2026! I bet you celebrated Earth Day in school growing up, or maybe you were in Scouting and partook in a day of litter clean-up. Whatever the case, I contend that you’ll think about how you spend Earth Day a little bit differently after reading this issue thanks to another Earth-themed holiday called Overshoot Day.

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Not the direction you thought this was heading, huh? Let me set the scene. It’s 1969 and, actually, we’ll let biologist Barry Commoner take it from here:

Now THAT sounds like a good time, eh?!

It was the era before environmental regulations, where dumping toxic wastes in rivers and spewing any ‘ole chemical we felt like it was seen as no big thang. And legal.

Yet the world was slowly awakening to the impacts of chemical use—DDT, in particular—on wildlife and ecosystems more broadly thanks to Rachel Carson’s 1962 publication of Silent Spring.

In the years that followed, Wisconsin Senator Gaylord Nelson teamed up with President John F. Kennedy on a speaking tour to spread awareness about the dangers of pollution and the state of the environment as it continued to worsen.

Then came 1969.

In January 1969, there was a massive oil spill in Santa Barbara, California. Union Oil received a waiver from the federal government to install only 236 feet of casing below the ocean floor for a new oil well instead of the required 300 foot minimum. Turned out 300 feet was the minimum for a reason.

For 11 days, oil spewed from the well into the Pacific Ocean at a rate of 9,000 gallons per hour. In total, around 3 million gallons of oil (equivalent to 4.5 Olympic swimming pools’ worth of oil) spread over 35 miles. It stands as the third-largest oil spill in the United States. (Yes, we’ve done worse.)

Later that same year, Cleveland, Ohio’s Cuyahoga River caught fire because it was so heavily laden with chemical waste.

Meanwhile, Senator Nelson (and millions of other Americans):

Earth Day was founded on April 22nd, 1970 after Senator Nelson organized 20 million Americans—which was 10% of the nation’s population at the time!—to take to the streets with the goal of getting environmental preservation on the national agenda.

In 1970, the US Environmental Protection Agency was born, along with the National Resources Defense Council, the Clean Air Act, the Clean Water Act, and a slew of other environmental wins.

So you’ve heard about Earth Day, and you’re now familiar with its history and the important precedent it sets for much of the United States’s landmark environmental legislation.

But it’d be silly to celebrate Earth Day without also acknowledging Overshoot Day.

Ever heard of it?

Overshoot Day is the day each year on which we, humans, have consumed one year’s worth of Earth’s annual biocapacity budget. Anything we use beyond this day is asking Mother Nature for seconds before she even has a chance to cook up another batch.

Pause. What’s an annual biocapacity budget?

It’s the capacity of ecosystems to provide whatever people demand in one year, whether it’s producing plants we eat or otherwise consume (e.g., timber) or absorbing waste materials. It varies year-to-year according to climate, resource management, and which commodities are trending.

It’s a report card for environmental resource consumption, so Overshoot Day changes every year depending on how well or poorly we use our resources.

Last year, Earth Overshoot Day fell on July 25th. That means that we scarfed down all the resources Mother Nature cooked up for one year with 159 days still left to go. It’s been getting earlier and earlier each year:

Zoom in to find out when Earth Overshoot Day would fall if everyone on Earth lived like the residents of that country:

If everyone on Earth lived like we do in the United States, we would use up the Earth’s yearly budget of resources on March 14th- just 73 days into the year.

If everyone lived like Hondurans do, we’d make it past Thanksgiving before using up our annual biocapacity budget.

Of course, there is a correlation here: a country’s resource consumption generally increases as it becomes more developed. The Overshoot Days of the world’s top four largest economies (the US, China, Germany, and Japan) all fall within the first half of the year. (India is the fifth-largest economy, but it’s excluded due to a low data quality score. For a complete list of which countries are excluded, click here.)

The other key takeaway? Not one country uses less than its fair share of resources for the year. We are all taking more from Mother Nature than we are receiving.

This Earth Day, we’re challenging you to treat this Earth Day like it’s New Year’s Day. What will you do differently over the next year that you didn’t do this past year?

Will you choose not to let your car idle anymore? But it’s just a quick trip inside!

Will you invest in an energy audit of your home to diagnose ways to save energy and 💲💲?

Will you opt to bike or carpool where you can?

I’m taking notes from Sam Balto.

On Earth Day 2022, Oregon gym teacher Sam Balto went viral after starting a “bike bus” for his students to ride their bikes to school safely. The bike bus operates just like a school bus, picking students up at their houses along the way to school. Except this bus reduces emissions, improves local air quality, and gives kids great exercise.

Because of Sam, there are fewer vehicles idling and more kids smiling. And dancing!

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We might have taken a weeklong break to celebrate Mother Nature, but we aren’t done with our Renewable Road Show series just yet!

Next week, we’ll cover hydroelectric energy, also called hydropower. Hydropower is one of the oldest forms of renewable energy out there because it relies on the natural gravitational flow of water to spin a turbine that creates energy.

It’s not a renewable energy source to overlook, either: No country has achieved a 100% renewable energy mix without relying on hydropower to some extent. In fact, hydropower accounts for 50% of global renewable energy production!

Tune in next week to learn how and why, and don’t get washed away in the meantime…

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