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----lE;czeg;mxt PHYSICAL OCEANOGRAPHY P H Y S I C A L O C E A N O G R A P H Y Introduction to I n t r o d u c t i o n t o Robert H Stewart R o b e r t H S t e w a r t Introduction to Physical Oceanography Robert Stewart Texas A&M University Copyright I hereby grant any user right to download and print a copy of the book for personal use. I also grant all teachers, lecturers, and professors the right to download the book and to make multiple copies for use by their students. The multiple copies may be made by copy centers. Students may be charged the cost of reproducing the book. I do not grant rights to the text for commercial purposes. Download the Book These files are the latest version, August 13, 2008. The files are in Adobe Portable Document Format. This version has hyperlinked Table of Contents and Index for easier navigation of the document in Adobe Acrobat Reader. I thanks Andrew Kiss of the University of New South Wales in Canberra Australia for his help in using the \hyperref package to produce the links. Book Complete book in a 9.6 Mbyte file with index. Cover Color cover for your book. If you don't have an Acrobat Reader, you can download one for free from Adobe. Introduction This is a new textbook describing physical-oceanographic processes, theories, data, and measurements. In addition to the classical topics, I have included discussions of heat fluxes, the role of the ocean in climate, the deep circulation, equatorial processes including El Nino, data bases used by oceanographers, the role of satellites and data from space, ship-based measurements, and the importance of vorticity in understanding oceanic flows. I have used the text to teach upper-division undergraduates and graduate students in oceanography, meteorology, and ocean engineering. Because many students have already taken courses that emphasize math, I have minimized the math and emphasized processes. Still, students should have studied differential equations and introductory college physics. The text is typeset and it has high-resolution figures produced by Adobe Illustrator CS2. The book was produced in LATEX2 ε using TeXShop 2.14 on an Intel dual-processor iMac running OS-X 10.4.11. The resulting typeset, 345 page, book.pdf file is only 9.5 Megabytes. If you make multiple copies I recommend you use a copy center that can make copies directly from the book.pdf file. These copies will be much better than copies made from printed pages. If you have problems, please contact me at stewart@ocean.tamu.edu Web Version A web-based version the book is also available.. What's New!! Fall 2008 Revisions This edition has a few minor and more important changes: Corrected a few minor errors. There are less and less thanks to the many readers who have found errors in the 1. Book PDF Files http://oceanworld.tamu.edu/resources/ocng_textbook/PDF_files... 1 of 4 11/9/14, 3:29 PM past. Added information about the new Reference Salinity scale in Section 6.1. 2. Corrected an important error in my discussion of potential temperature in Section 6.5. 3. Added information about MODIS and Jason-2. 4. Removed references to controversy about vertical mixing in the ocean in Section 8.4. The controversy has been resolved. 5. Added more information about abrupt climate at end of the last ice age in Section 13.1. 6. Added more information about mixing driving the deep circulation in Section 13.3 and , and the role of Ekman pumping in the Antarctic and its influence on the deep circulation in Section 13.5 7. Added information about measured variability of the North Atlantic meridional overturning circulation in Section 13.4. 8. Removed information about solitons in Section 16.2. It is not that important in an introductory text that is alreay too long. 9. The table below links to the latest version of Introduction to Physical Oceanography in Adobe Acrobat Portable Document Format (pdf files). The files may be downloaded and printed if you wish a nice printed copy of the book. Altogether, there are viii + 345 pages in the book. Fall 2007 Revisions This edition has several changes from the previous edition. The changes include: Mostly many small changes and corrections of minor errors. I thank all of you who have emailed comments to me this year. 1. COADS has been changed to the new ICOADS. 2. Revised section on definition of salinity to separate definition from extensions of definition to typical temperatures found in the ocean. 3. Revised section on temperature to refer to the new Smith and Reynolds Improved Optimal Interpolation scheme. 4. Added information on Prandtl's discovery of the boundary layer and its importance to oceanography 5. Revised paragraphs on altimeter errors to include more accurate values now being achieved for Jasin and Topex/Poseidon. 6. Revised figure 12.7 to show western intensification. 7. Clarified importance of equatorial heating for atmospheric circulation, and role of el Nino. 8. Added information on the Advanced Circulation Model for coastal processes and storm surges. 9. Fall 2006 Revisions This edition has several changes from the previous edition. The changes include: Updated information on maps of seafloor features and global bathymetric maps. 1. Revised section on measurements of winds to better describe satellite measurements of winds. 2. Revised section on measurements of currents to state more clearly the important techniques and drop less important information. 3. Dropped the description of fresh-water transports. I think the topic is beyond the scope of the book. 4. Made a few minor changes in wording and corrected a very small number of typographical errors. I thank all of you who have found almost all errors in previous years. 5. As a result, the book is one page shorter this year. 6. Fall 2005 Revisions The files below are the latest version, August 10, 2005. This edition has only minor changes from the previous edition. The changes include: Clarified the discussion of important forces in Chapter 7. 1. Dropped all statements that a derivation is simple. It may be simple to some, but not to many students. 2. Added a new figure on Ekman flow in Chapter 9. 3. Revised the discussion of flow into and out of the Mediterranean Sea in Chapter 7. 4. Book PDF Files http://oceanworld.tamu.edu/resources/ocng_textbook/PDF_files... 2 of 4 11/9/14, 3:29 PM Made a few minor changes in wording and corrected a few typographical errors. 5. Fall 2004 Revisions This edition has only minor changes from the previous edition. The changes include: Deleted all references to the practical salinity unit (psu). It doesn't exist. Salinity is a dimensionless ratio of masses. 1. Clarified the derivation of Margules' equation on page 171. 2. Made a few minor changes in wording and corrected a few typographical errors. 3. Spring 2004 Revisions This edition has only minor changes from the previous edition. The changes include: Revision of discussion of using vorticity to explain western boundary currents on page 204-205. 1. Changed explanation of tide generating forces on page 301. 2. Corrected error in equations describing the Ekman layer on page 139. 3. Corrected errors in figure 3.2. 4. Clarified differences between a surface analysis and reanalyzed weather data on pages 47. 5. Made a few minor changes in wording and corrected a few typographical errors. 6. Fall 2003 Revisions The important changes include: Many figures have been redrawn, some have been replaced. 1. The index is much improved. 2. Many references have been deleted or added. The calls to references in the text now agree with references at the end of the book. 3. Chapter 13 on the deep circulation has been revised to include recent advances in our understanding of the deep mass flow. Out is any reference to the thermohaline circulation (it is used in too many conflicting ways). In is the information that the deep flow is driven by wind and tidal mixing. 4. Hundreds of minor revisions throughout the book. 5. Fall 2002 Revisions The important changes include: We have an index! Trey Morris, a student, spent the summer tagging all the LaTeX files used to make the book. From these we produced an index and the pdf files below. 1. Don Johnson, another student, spent months redrawing many figures. 2. I simplified some of the discussions of errors. I found that students jumped to the conclusion that if there were several sources of error, no matter how small, the data were essentially worthless. This shortened the book by seven pages. 3. I made hundreds of small changes to the text. 4. Spring 2002 Revisions The important changes include: Gradually replacing poor scanned images with newly redrawn figures. 1. Corrected some significant errors in Chapter 10: tables had wrong values in one column, and text describing how currents are calculated from measurements of density was confusing 2. Many minor changes in all chapters. 3. The book is one page longer. 4. Adobe index file added. 5. Book PDF Files http://oceanworld.tamu.edu/resources/ocng_textbook/PDF_files... 3 of 4 11/9/14, 3:29 PM Fall 2001 Revisions The important changes include: A beautiful cover. 1. Clarified the values for vertical diffusivity removing the conflict between Munk's value and measurements. 2. Revised the discussion of Ekman pumping and the role of vorticity in section 12.3. 3. Revised section 6.5 on density. 4. Added a description of neutral density. 5. Revised or redrew many figures. 6. Corrected many, many typos and other minor irritating errors. 7. The book is a few pages shorter. 8. Plus, I learned more about Adobe Illustrator 9 and Distiller 5 than I ever wanted to know. My testing leads me to believe the pdf files will print correctly. 9. Fall 2000 Revisions I have revised many sections of the book, added new figures illustrating key concepts, and corrected many small errors. The important changes include: More information on double diffusion. 1. Much revised section on Ekman currents. 2. Added description of the North Atlantic circulation in chapter 10, including discussion of the Gulf Stream and negative viscosity. 3. Clarified that vertical mixing drives the deep circulation, and added a description of the Antarctic Circumpolar Current in Chapter 13. 4. Revised discussion of El Nino/La Nina. 5. Dropped the old Chapter 15 on the observed circulation of the ocean and added the information to other chapters. 6. Department of Oceanography, Texas A&M University Robert H. Stewart, stewart@ocean.tamu.edu All contents copyright © 2008 Robert H. Stewart, All rights reserved Updated June 3, 2009 URL: http://oceanworld.tamu.edu/resources/ocng_textbook/PDF_files/book_PDF_files.html Book PDF Files http://oceanworld.tamu.edu/resources/ocng_textbook/PDF_files... 4 of 4 11/9/14, 3:29 PM Introduction To Physical Oceanography Robert H. Stewart Department of Oceanography Texas A & M University Copyright 2008 September 2008 Edition ii Contents Preface vii 1AVoyageofDiscovery 1 1.1 Physics of the ocean ......................... 1 1.2 Goals ................................. 2 1.3 Organization ............................. 3 1.4 The Big Picture ............................ 3 1.5 Further Reading ........................... 5 2TheHistoricalSetting 7 2.1 Definitions ............................... 8 2.2 Eras of Oceanographic Exploration ................. 8 2.3 Milestones in the Understanding of the Ocean ........... 12 2.4 Evolution of some Theoretical Ideas ................ 15 2.5 The Role of Observations in Oceanography ............ 16 2.6 Important Concepts ......................... 20 3ThePhysicalSetting 21 3.1 Ocean and Seas ............................ 22 3.2 Dimensions of the ocean ....................... 23 3.3 Sea-Floor Features .......................... 25 3.4 Measuring the Depth of the Ocean ................. 29 3.5 Sea Floor Charts and Data Sets ................... 33 3.6 Sound in the Ocean ......................... 34 3.7 Important Concepts ......................... 37 4AtmosphericInfluences 39 4.1 The Earth in Space .......................... 39 4.2 Atmospheric Wind Systems ..................... 41 4.3 The Planetary Boundary Layer ................... 43 4.4 Measurement of Wind ........................ 43 4.5 Calculations of Wind ......................... 46 4.6 Wind Stress .............................. 48 4.7 Important Concepts ......................... 49 iii iv CONTENTS 5TheOceanicHeatBudget 51 5.1 The Oceanic Heat Budget ...................... 51 5.2 Heat-Budget Terms .......................... 53 5.3 Direct Calculation of Fluxes ..................... 57 5.4 Indirect Calculation of Fluxes: Bulk Formulas ........... 58 5.5 Global Data Sets for Fluxes ..................... 61 5.6 Geographic Distribution of Terms .................. 65 5.7 Meridional Heat Transport ..................... 68 5.8 Variations in Solar Constant ..................... 70 5.9 Important Concepts ......................... 72 6Temperature,Salinity,andDensity 73 6.1 Definition of Salinity ......................... 73 6.2 Definition of Temperature ...................... 77 6.3 Geographical Distribution ...................... 77 6.4 The Oceanic Mixed Layer and Thermocline ............ 81 6.5 Density ................................ 83 6.6 Measurement of Temperature .................... 88 6.7 Measurement of Conductivity or Salinity .............. 93 6.8 Measurement of Pressure ...................... 95 6.9 Temperature and Salinity With Depth ............... 95 6.10 Light in the Ocean and Absorption of Light ............ 97 6.11 Important Concepts .........................101 7TheEquationsofMotion 103 7.1 Dominant Forces for Ocean Dynamics ...............103 7.2 Coordinate System ..........................104 7.3 Types of Flow in the ocean .....................105 7.4 Conservation of Mass and Salt ...................106 7.5 The Total Derivative (D/Dt) ....................107 7.6 Momentum Equation .........................108 7.7 Conservation of Mass: The Continuity Equation .........111 7.8 Solutions to the Equations of Motion ................113 7.9 Important Concepts .........................114 8EquationsofMotionWithViscosity 115 8.1 The Influence of Viscosity ......................115 8.2 Turbulence ..............................116 8.3 Calculation of Reynolds Stress: ...................119 8.4 Mixing in the Ocean .........................123 8.5 Stability ................................127 8.6 Important Concepts .........................131 https://www.colorado.edu/oclab/sites/default/files/attached-files/stewart_textbook
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