Today is the 40th anniversary of Earth Day. First declared in the spring of 1970, Earth Day saw millions of students and citizens gather in a giant nation-wide teach-in to save the earth.
The nation was divided over the Vietnam War, but we seemed to be able to agree on one thing -- the need for better environmental protection.
Today, there's little agreement on the main environmental issues we face.
For a lot of us, our first awareness of environmental issues came from an Earth Day event at school.
Catherine Conzet was in middle school in the spring of 1970. She and her classmates spent most of the first Earth Day picking up litter.
"There were cans, newspapers, fast food things, and this was 1970 when there was actually less of that stuff around," Conzet said. "From that day on, I was determined I certainly was never going to throw anything on the ground, and I never have."
Those early Earth Days probably spawned at least one generation horrified by litter, but a recent Gallup poll showed Americans are no more environmentally friendly in their actions today than they were 10 years ago. And they're more likely to reduce energy use, for instance, to save money, not to help the planet.
Dean Abrahamson taught energy and environmental policy at the University of Minnesota for many years. He remembers a sign posted by the Mississippi River below Coffman Union, saying the water was "unsafe for bodily contact." Now you can swim in the Mississippi.
"Local, short-term, housekeeping things have gotten much better," Abrahamson said. "But the big environmental issues have gotten worse, much worse."
Perhaps the biggest and most contentious issue today is global warming and what to do about it, but polls show fewer Americans today believe that climate change is real and that humans are responsible for it. One person who's seen the impact of global warming first-hand is primate researcher Jane Goodall:
"I was just in Greenland, and I heard these huge slabs of ice break off this giant ice cliff that goes up to the top of the world, and the rumbling reverberating roar as these slabs of ice dropped down inside the ice cliff, and the water gushing out, where before, the elders told me, 30 years ago the ice never melted even in the summer.
And I went directly from there to Panama, where the elders of the Kuna people had made arrangements to evacuate the islands one by one where their people have lived for hundreds of years because the sea levels are already rising."
A lot of people want to do something about climate change; some are even willing to change their own lifestyles. But it's not always clear what to do.
Daniel Sola, a hydrogeologist who cleans up contaminated sites for a living, said even he gets confused with the choices.
"Buy local: I love buying local. But is it greener to go to the farmers market where 100 farmers drive into town in a pickup truck or is it greener to go to a grocery store where one semi-truck brings in the vegetables? I don't know," Sola said.
Sola said we need to engage in an honest conversation about the environment. He said, as citizens, we need to work harder to understand the science of how the world works, and we need to trust what science can tell us. These days we don't seem to trust anything, especially when politicians start talking.
Goodall said that on Earth Day 2010, individual choices are as important as the public debate.
"I always suggest that people try to spend a little bit of time thinking about the consequences of the choices they make each day, what they eat, what they wear, how they get from A to B, how they interact with people, and I find that when people start thinking like that, they do start making change," she said.
That's what Earth Day was about 40 years ago, and according to Goodall, that's what it's about today.