Steve Setford - Did You Know? Ocean

Steve Setford

The blue planet Where did Earth s water come from? 1011 H ow old are the oceans? 1213 How is the ocean diff erent fro m the sea? 1415 H ow deep is the ocean? 1617 W hich is the largest ocean? 1819 W hy is the ocean blue? 2021 D oes the ocean ever stand still? 2223 C an ocean water freeze? 2425 W hy doesnt the ocean dry up? 2627 W hy is the ocean salty? 2829 W hy do oceans have waves? 3031 H ow often does the tide turn? Ocean features 3435 W hat is a tsunami? 3637 I s the ocean floor flat? 3839 A re there volcanoes underwater? 4041 W hy do icebergs float? 4243 H ow do islands form? 4445 W hy are some coasts sandy and others rocky? 4647 W here does sea foam come fro m? 4849 D oes the ocean floor move? 5051 I s coral alive? Ocean habitats 5455 D oes grass grow in the ocean? 5657 W hat lives on the seabed? 5859 W hat lives in a rock pool? 6061 W hy are mudflats smelly? Author Steve Setford Consultant Der ek H arvey Smithsonian C onsultant Dr . Dave Pawson Senior S cientist, E meritus, C urator o f Echin oderms National M useum of Natural History , Smithson ian Illustrator Dan Crisp DK LONDON Senior E ditor Mar ie Gre enwood Senior Art Editor Ann Cannings US Editor Mar garet P arrish US Senior Editor Sha nnon Beat ty Managing E ditor Jonathan Melmoth Managing Art Editor Dia ne Peyton Jones Production E ditor Dra gana Puva cic Production C ontroller Mag dalena Bojko Jacket Des igner Ann Cannings Publishing C oordinator Iss y Wa lsh Deputy Ar t Dire ctor Mab el Chan Publishing D irector Sar ah Lar ter DK DELHI Senior Editor Roohi Sehgal Senior Art Editor Nidhi Mehra Project A rt Ed itor Kanika Ka lra Art Editor Bhagyashree N ayak Managing E ditor Monica Saig al Managing A rt Edito r Romi Chakrabort y Jacket Des igner Dhe eraj Aro ra DTP Desig ners Dheeraj Sing h, Syed Md F arhan CTS Manager Balwant Sing h Production M anager Pankaj Shar ma Project P icture R esearcher Sakshi S aluja Delhi Cre ative H eads Glenda Fer nandes, Malavika T alukder First A merican e dition, 2 Published i n the United States by D K Publi shing 1450 Bro adway , Suite 801, New Y or k, NY 10018 Copyright 2022 Dorling Kindersl ey Limit ed DK, a Division of P enguin Ran dom House LLC 22 23 24 2 5 26 10 9 8 7 6 5 4 3 2 1 001326665Mar/2022 All ri ghts re served. Without limitin g the rights under the copyrig ht re served a bove, no part of t his pub lication m ay be re produced, s tored i n or intro duced i nto a re trieval s ystem, o r tran smitted, i n any form, o r by any means (electro nic, mec hanical, p hotocopying, recordi ng, or other wise), w ithout t he pri or wri tten p ermission of the copyright owner . Published i n Gre at Brit ain by Dorling Kinder sley Li mited A catal og re cord f or thi s book is avai lable f rom t he Lib rary o f Cong ress. ISBN 978-0-7440- 5007-3 DK books are availa ble at special discou nts whe n purc hased i n bulk for sales pro motions, p remiums, f und-raising, o r educa tional use. For details, contact: DK Publishing Special Markets, 1450 Bro adway , Suite 801, New Y or k, NY 10018 SpecialSales@dk.com Printed an d bound in C hina For the curious www.dk.com This book was made with F or est Stewardship Co uncil cert ifi ed paper one small step in DKs commitment to a sustainable future. Fo r more informat ion go to www. dk.com/our-gr een-pledge Smithso nian

6263 W hat are estuaries? 6465 Why is a coral reef so colorful? 6667 W hat are the hottest parts of the ocean? 6869 Can trees gr ow in salty water? 7071 Why dont polar animals fr eeze? 7273 Do flowers grow in the ocean? 7475 A re there forests in the ocean? Ocean life 7879 How does sunlight power ocean life? 8081 W hy do the biggest animals live in the ocean? 8283 How do sea animals use camoufl age? 8485 A re octopuses r eally brainy? 8687 C an fish see in the dark? 8889 W hat are the biggest ocean predators? 9091 D o fish migrate like birds? 9293 W hat lives in the ocean depths? 9495 H ow fast can fish swim? 9697 W hy do dolphins leap? 9899 D o fish sleep? 100101 H ow do birds survive at sea? 102103 W hat happens to sea animals when they die? 104105 D o sea serpents exist? Oceans and us 108109 H ow do oceans help us? 110111 H ow do we farm fish? 112113 W hat causes a shipwreck? 114115 A re sea levels rising? 116117 Why is plastic so harmful to ocean life? 118119 H ow does a submarine dive? 120121 W hich sea creatur es are in danger? 122123 H ow do hurricanes form? 124125 W hen is fishing a problem? 126127 H ow do underwater robots work? 128129 H ow do we study the oceans? 130131 How can we take care of the oceans? 132133 Answers 134137 Quiz your friends! 138139 Glossary 140143 Index C redits and acknowledgments Find out how birds survive at sea on page 100. Find out why polar animals dont freeze on page 70. Q Q u u i i c c k q k q u u i i z z ? ? Te st your knowledge! Look for the Quick quiz boxes throughout this book to see how much youve learned. Y oull nd some of the answers on the pages, but you may have to look up or make your best guess for the others. T urn to pages 132133 for the answers.

Seen from space, Earth is a blue planeta world cover ed mostly by salty water . Since the rst oceans formed, they have been constantly on the move, whipped by winds into waves and pulled by the moon into tides, with curr ents sur ging at the surface and deep below .

About 4.5 billion years ago, when Earth rst formed, water was probably alr eady pre sent in the rocks that clumped together to create the planet. This water was released and found its way to the surface. The r est of Earth s water came from space. Wate r vapor hung in Earths atmosphere until Earth cooled below 212F (100C) and then the fi rst rain came. Clouds form Gases and water vapor formed Earth s early atmosphere. As the atmosphere cooled, the water vapor condensed into clouds. Vol canic eruptions You ng Earth was covered with volcanoes. When the volcanoes erupted, they spewed out hot gases and water vapor from deep below the surface. THE BLUE PLANET