Editor's note: Bill Nye is an Emmy-winning TV host as well as a scientist, engineer, comedian, author and inventor. He is best known to television audiences as "Bill Nye the Science Guy."
Los Angeles, California (CNN) -- There were several speeches at the first Earth Day -- back in 1970, before the disco era -- on the National Mall. Back then, it was about pollution -- fighting pollution. Now, it's about not just trash and crazy unnatural chemicals, it's about climate change. It's not just that there's more trouble; it's more of a desperate situation.
I rode to the Washington Monument that day on my bicycle wearing a sign that read "Pedals Don't Pollute." I rendered the "o" in Pollute as the original Earth symbol from that early era. It has an equator and is reminiscent of the Greek letter theta. Even if I wasn't as cool and thoughtful as I hoped to appear, the first Earth Day's message was good then, and it's better today: We have to take care of the Earth. Or the Earth, in hit-man style, will see to it that a great many of us are "taken care of."
When we think of Earth Day, many of us think of good ol' hippies bent on living off the electrical grid, drinking spring water from somewhere and recycling everything -- bottles, shoes and lint maybe. Their battle cry: "Save the Earth."
Well, saving the Earth might be a reasonable pursuit. But the Earth is going to be fine. It's been here 4.5 billion years. What we want to do, and Earth Day reminds us of this, is save the Earth for us ... for you and me. We want to keep the Earth in about the same shape we found it, so that most of us can keep living here.
I'm talking about billions and billions of us. My father and I were disappointed to arrive at the 1965 New York World's Fair after the scoreboard-style lighted display on the Earth's population changed from 2,999,999,999 people to a bit over 3 billion. To watch all those numbers change would have been wondrous, like the joy one gets when the car odometer flips over to 100,000 miles or kilometers.
Well, now my friends, 40-plus years later, we have more than doubled that population number to 6.8 billion. People. On Earth.
There is no question that if each of us on the planet tries to live the way people do in the parts that are considered the developed world, we won't make it. The Earth does not have enough clean water, good pasture land or even livable space along coasts to have everyone in, say, the poorer areas of western China and central India living and driving the way we do in, say, northern Virginia.
In response to this clear but astonishing state of affairs, we could try just doing less. Drive less; use less clean water and wear dirty clothes. In fact, how about if humans, like you, just don't eat?! For me, this self-denial approach would be more in keeping with your old, or early, Earth Day.
But no. Instead, what we have to come up with are ways to do more with less. This is what Earth Day has become.
We need to be conservationists to be sure, preserving wetlands, forests, open spaces and coastlines. We need to reduce our waste -- plastic trash and the like. But what we really need is big, new ideas: new ways to distribute and store energy for electric power, new ways to conserve and distribute clean water for farming and gulping, and new ways get ourselves and our cargo around, so that we don't change the Earth's climates too much as we burn our fossil fuels.
I used to believe that all we had to do was become efficient, or less inefficient. I used to think that if we just stopped squandering water, forests and electrical power, we'd improve the environment and preserve our environments around the world.
Nowadays though, I'm thinking that we are going to need extraordinary measures soon. For one thing, we're going to need to cool the planet somehow, probably by reflecting some sunlight back into space. How about if we turned that giant island of plastic trash floating in the Pacific Ocean Gyre into a mirror or shade, or something?
Climate change is going to challenge us like nothing else in human history. It's going to take big ideas that work, and big ideas that allow regulations to be enforced in harmony.
Look at a picture of our world from space. The atmosphere is often not even visible. If you could drive straight up into outer space, you'd be there in less than an hour. Our atmosphere is so very thin, and we're changing its mixture of gases with our activities. We're trapping heat and warming our world.
This Earth Day, keep in mind that each of us affects everyone else on Earth, because we all share the land, the ocean and especially the air on what is proving to be a pretty small planet. Let's take care of it.
Happy Earth Day.
The opinions expressed in this commentary are solely those of Bill Nye.