Planet Earth's nine lives: Our planet's limits
Big world? No, it's a small world
To you and me, the world seems absolutely huge. Lots of people think this and that's the reason why humans to this day use the land, sea and air to dump all the waste they make. But isn't the amount of waste people make really tiny when you think of the vast size of the seas, lands and atmosphere? When there weren't many people (and they lived in quite a simple way with no cars, planes, computers or electricity), that was true enough. But it's all changed: there are now 7 billion humans on the planet making a whole lot of wasteWaste energyHow much stuff do you and your family throw away every day? How much fuel do you burn in your family car and house heating or cooling system? Probably far more than you'd think. Then multiply by 7 billion...!. This really is damaging the air, the sea and the land. By waste I mean pollution including, especially, greenhouse gases like carbon dioxide. Humans are also guzzling stuff which the planet only has in limited amounts. Stuff like oil, gas and coal (to power human industry), minerals, fresh water, fish, forests. All these are resources which will run out or are being destroyed faster than the planet's natural systems can replace them.
The number of people on the planet grows at the rate of about seventy-five million every year. But the planet is not getting any bigger. The total number of humans is 7 billion, weighing in at around 4.5 million tons. Every person eats around 25 tons of food over their lifetime. All of this - apart from some seafood - has to come from farming. People are already using over one tenth of the land - 16 million square kilometres - for growing food. People also cover land with concrete and asphalt for cities and roads. Mining takes coal, oil, gas and minerals out of the Earth, which can't be replaced. Taking out and using these minerals causes pollution everywhere, most of which you don't see. People are cutting and burning forests and mostly not replacing them.
I know our planet seems big but it's not so big as you might have thought. It is finite: it has its limits. And there's only one planet for all of us. There's no backup; no new continents to be discovered; no other habitable'Habitable' means somewhere you can live planets for people, penguins or any other wildlife to go!