INTRODUCTION Do you ever feel surrounded by stuff Like when you look around a huge store with floor-to-ceiling shelves filled with stuff Or in your own room enclosed by stuff Everywhere stuff Picture your neighborhood on garbage collection day Are the streets overflowing with trash cans and recycling bins Do you wonder what happens to all the stuff that gets thrown away Or maybe you’ve never thought too much about it The garbage gets collected and that’s the end But of course that’s not the end Whether it’s new in the store or trash in the bin everything is part of a life cycle from harvesting raw materials to manufacturing packaging transporting and selling to using and consuming and finally to trashing or recycling This book is about the waste cycle the trashing or recycling stage and how we get there and what we can do about it Your World in a Backpack Do you carry a backpack to school If you think about it a backpack can hold almost everything we need to survive and communicate water food clothing paper and perhaps an electronic communication device In every chapter of this book except when we visit outer space we’re going to take a look at something you might carry in your backpack to school We’ll see how it is produced and what happens to it when it becomes waste 6
The recycling logo represents the continuing life cycle of a product It is an endless loop never causing waste The logo was designed by Gary Anderson in 1970 when he was a student at the University of Southern California He won a contest sponsored by the Container Corporation of America His symbol is now universally recognized Trash Talk When it comes to trash there’s a lot to talk about Some estimates suggest that every one of us will produce 600 times our own weight in waste over the course of our lifetimes But all that talk also includes what innovators see when they look at waste They look at water in the toilet and say Mmm drinking water They see animal poo at the zoo and say Excellent There’s more fuel Scientists and students and regular people the world over are coming up with new ways to harness the power of waste every day Open-Loop versus Closed-Loop Systems When we buy something use it and throw it away that’s what we call an open-loop system Objects are just discarded with no new purpose For a long time that was considered no big deal There were fewer of us on the planet and we had tons of resources to use and endless space to dump the waste Now however that’s not the case Because of our new awareness the future of waste will include more closed-loop systems That means that the end is just a new beginning For example in a closed-loop system recycling can turn a used aluminum can into a new can The heat created from running a recycling facility can be captured and used to heat the building And when you design something to be reused instead of trashed or recycled the waste savings are huge Supply and Demand You may have heard the term supply and demand Let’s say everyone in your class of 20 students wants to own this book Totally understandable That’s demand But the store has only 10 copies That’s supply In this example demand exceeds supply The rules of supply and demand apply to water paper metal everything around you The trick is to balance our personal wants and needs with the world’s supply Each chapter in this book ends with a look at supply and demand and what you can do to reduce reuse or recycle waste Sometimes you can change the world simply by changing your demands More and more we’re learning how what we buy use and throw away affects the planet The great news is that you’re reading this book That means that you care about waste and want to learn more Or some adult is standing nearby and you want to look like you care Either way keep reading 7
WATER Do you have a reusable water bottle in your backpack that you fill at home or at school Beyond the tap and water fountain where does that water begin Where does it end The Water Cycle It may seem that when it rains water comes from an endless supply in space But rain is part of the water cycle here on Earth The water cycle also called the hydrologic cycle recycles the same water over and over 1 Evaporation The sun provides heat energy The sun evaporates water from the oceans lakes rivers and streams It becomes water vapor 2 Transpiration Water also evaporates from the leaves of plants 3 Condensation Water vapor rises into the atmosphere where the air is colder There the water vapor condenses into clouds 4 Precipitation Air currents move clouds around the Earth Water droplets form inside clouds Droplets fall to Earth as rain and snow precipitation 5 Collection Rain melted ice and snow flow into the ground and waterways Water older than the sun Scientists think water may be even older than the sun Why They have tested water for clues The formula for water is H2O which means two hydrogen atoms are bonded to one oxygen atom But some water molecules also contain an extra molecule called deuterium Deuterium water exists on other planets and moons and in small parts on Earth How did it get here Scientists think it may have traveled in a giant cloud across the solar system before the sun began to burn 4.6 billion years ago Tastes pretty fresh for water that’s billions of years old doesn’t it 8
Where on Earth Is Our Water Fresh water 79 frozen in ice caps and glaciers 20 groundwater 1 surface water Earth’s water Salt water 97 Fresh water 3 Only 3 percent of Earth’s total water is fresh water We need fresh water for drinking Most drinking water is tap water and it comes from surface water or groundwater Rivers lakes and reservoirs are surface water easily accessible to us Water pumped from wells drilled into aquifers is groundwater What’s an aquifer Picture a dog at the beach digging a hole in the sand If the dog digs deep enough it will hit water This water comes from an aquifer a layer of rock that water can seep through The groundwater comes to the surface either naturally as in a spring or by being pumped up to the surface as in a well The not-great news Reverse osmosis requires a lot of The salty sludge left over could affect delicate ecosystems in the ocean or ground like if you poured a pile of salt into your soup it just wouldn’t taste right Don’t Drink the Salt Water If 97 percent of our water comes from oceans and seas it makes sense to investigate drinking that water Ocean water is saline though which means it has a high concentration of salt in it Drinking it would make us sick energy Desalination is the process of removing salt from water For years people boiled the salt from water using evaporation or distillation Now water is forced through cartridges that trap the salt in a process called reverse osmosis 9 The better news In nature rain falls to the ground collecting and dissolving minerals The heat energy of the sun evaporates the water and leaves the salt behind Scientists are working on desalination systems that use solar panels to copy nature’s own process
