Take nothing but pictures; leave nothing but footprints.
- Traditional conservation saying, used by the U.S. National Park Service and many environmental organizations
CLEAN brings one aspect of green/sustainable living into focus
What do we leave behind?
We will always leave something behind. The question is how much, what kind, and whether Earth's natural systems can handle it.
It means leaving behind what the Earth and its living systems can safely absorb, break down, store, or cycle back through the environment.
Natural systems can manage an enormous amount of material. But when we add too much, too quickly — or make something that is especially difficult to break down — those systems may not be able to keep up.
Fossil fuels: releasing ancient carbon into the atmosphere
Fossil fuels — coal, oil and gas — are by far the largest contributor to global climate change.
—United Nations
Coal, oil, and natural gas contain carbon that became stored underground over millions of years.
We bring these fossil fuels to the surface and burn them for energy. When they burn, much of their carbon combines with oxygen in the air and becomes carbon dioxide, or CO₂. CO₂ is already part of Earth's natural carbon cycle. Plants take it in, oceans absorb it, and other natural processes move and store carbon. The problem is the pace: we're releasing additional CO₂ faster than natural systems can take it back out.
Carbon that took millions of years to become stored underground is being released in a matter of generations. As CO₂ builds up in the atmosphere, it traps more heat, warming the planet and changing the climate that life depends on. Oil and natural gas aren't only burned as fuels. They're also used as raw materials to make plastics and many other products.
Many conventional plastics don't readily fit back into natural cycles. They may break into smaller and smaller pieces — including microplastics — without becoming something nature can readily use again. So whether we're talking about CO₂ or plastic, the question comes back to the same thing:
Can Earth's natural systems keep up with what we're leaving behind?
What can we do?
Start with the energy you use. Look at your utility company's website, or call and ask whether you can choose electricity from lower-carbon sources such as wind or solar. What's available depends on where you live.
Think about how you get around. Walk or bike when it's practical. Use buses, trains, trams or subways when they're available. And if your community doesn't give you good choices, ask for them. The name of the person to contact is probably online.
Drive less or share a ride. If you're replacing a car, consider an efficient hybrid or electric vehicle. It doesn't necessarily have to be new — buying used is another way of making use of something that already exists.
When we fly, the takeoffs and climbs are very fuel intensive, so for shorter trips consider other options.
Because oil and natural gas are also used to make plastics, we can use less disposable plastic, choose products with less packaging, reuse what we can, and recycle what our local recycling programs accept.
