Something up there traps Earth's warmth like a door that only opens one way. Let's find out what — and why it keeps turning up the heat.
Open the caseSunlight pours through the sky like it owns the place and warms the ground. The ground glows that warmth back out as invisible heat — but greenhouse gases catch a lot of it on the way up. Light gets in easy. Heat barely gets out.
A thin layer of these gases is actually a good thing — without it, Earth would be a frozen ball of ice. The trouble is we keep adding more and more of it. The door keeps getting stickier, and the heat keeps piling up.
Every tap drops a little greenhouse gas into the air. Watch the heat try to escape to space — and watch how much gets bounced right back down.
Yellow = sunlight coming in. Red = heat trying to leave. The more gas you add, the more heat gets bounced back down — and the hotter Earth gets.
Almost anywhere we burn coal, oil, or gas to make power or go places, greenhouse gas puffs out into the air. Here are the biggest sources.
Cars, buses, ships and planes burn fuel — and breathe out greenhouse gas as they go.
Lots of electricity still comes from burning coal and gas in giant power plants.
Factories that make steel, cement and plastic run hot — and let off a lot of gas.
Cows burp a powerful gas called methane, and clearing land for farms adds more.
Trees drink in greenhouse gas. Cut them down, and there's nothing left to soak it up.
Warming and cooling billions of buildings burns a surprising amount of fuel too.
These two mix-ups trip up grown-ups all the time. Tap a card to flip it over and bust the myth.
Here's the hopeful part: the heat isn't stuck forever. Add less gas, and the door un-sticks — Earth can settle back down. We already know exactly how.
Sun and wind make electricity without burning anything — no extra gas at all.
More trees and forests pull greenhouse gas straight back out of the air.
Walking, biking, trains and electric cars get us around with far less gas.
Switching off, wasting less food, and reusing stuff all means less burning.
None of this is too big for a kid. Asking questions, sharing what you've learned, and nudging the grown-ups around you — that's where it starts.
Three quick questions. Tap your answer to see if you've got it.
Sunlight sails through the sky and warms the ground.
The warm ground glows that heat back out toward space.
Greenhouse gas catches the heat. Too much, and Earth overheats.