Second Order Draft Chapter 3 IPCC WGI Fifth Assessment Report 1 2 Chapter 3: Observations: Ocean 3 4 Coordinating Lead Authors: Monika Rhein (Germany), Stephen R. Rintoul (Australia) 5 6 Lead Authors: Shigeru Aoki (Japan), Edmo Campos (Brazil), Don Chambers (USA), Richard Feely (USA), 7 Sergey Gulev (Russia), Gregory C. Johnson (USA), Simon A. Josey (UK), Andrey Kostianoy (Russia), 8 Cecilie Mauritzen (Norway), Dean Roemmich (USA), Lynne Talley (USA), Fan Wang (China) 9 10 Contributing Authors: Michio Aoyama, Molly Baringer, Nicholas R. Bates, Timothy Boyer, Robert Byrne, 11 Sarah Cooley, Stuart Cunningham, Thierry Delcroix, Catia M. Domingues, John Dore, Scott Doney, Paul 12 Durack, Rana Fine, Melchor González-Dávila, Simon Good, Nicolas Gruber, Mark Hemer, David Hydes, 13 Masayoshi Ishii, Stanley Jacobs, Torsten Kanzow, David Karl, Alexander Kazmin, Samar Khatiwala, Joan 14 Kleypas, Kitack Lee, Eric Leuliette, Calvin Mordy, Jon Olafsson, James Orr, Alejandro Orsi, Geun-Ha Park, 15 Igor Polyakov, Sarah G. Purkey, Bo Qiu, Gilles Reverdin, Anastasia Romanou, Raymond Schmitt, Koji 16 Shimada, Lothar Stramma, Toshio Suga, Taro Takahashi, Toste Tanhua, Sunke Schmidtko, Karina von 17 Schuckmann, Doug Smith, Hans von Storch, Xiaolan Wang, Rik Wanninkhof, Susan Wijffels, Philip 18 Woodworth, Igor Yashayaev, Lisan Yu 19 20 Review Editors: Howard Freeland (Canada), Silvia Garzoli (USA), Yukihiro Nojiri (Japan) 21 22 Date of Draft: 5 October 2012 23 24 Notes: TSU Compiled Version 25 26 27 Table of Contents 28 29 Executive Summary..........................................................................................................................................3 30 3.1 Introduction ..............................................................................................................................................6 31 3.2 Changes in Ocean Temperature and Heat Content ..............................................................................6 32 3.2.1 Background: Instruments and Sampling.........................................................................................6 33 3.2.2 Upper Ocean Temperature .............................................................................................................7 34 3.2.3 Upper Ocean Heat Content.............................................................................................................8 35 3.2.4 Deep Ocean Temperature and Heat Content..................................................................................9 36 3.2.5 Conclusion ....................................................................................................................................10 37 Box 3.1: Change in Global Energy Inventory..............................................................................................10 38 3.3 Changes in Salinity and the Freshwater Budget .................................................................................11 39 3.3.1 Introduction...................................................................................................................................11 40 3.3.2 Global to Basin-Scale Trends .......................................................................................................12 41 3.3.3 Regional Changes in Salinity........................................................................................................13 42 3.3.4 Evidence for Change of the Global Water Cycle from Salinity ....................................................14 43 3.3.5 Conclusion ....................................................................................................................................15 44 3.4 Changes in Ocean Surface Fluxes .........................................................................................................15 45 3.4.1 Introduction...................................................................................................................................15 46 3.4.2 Air-Sea Heat Flux .........................................................................................................................15 47 3.4.3 Ocean Surface Precipitation and Freshwater Flux ......................................................................17 48 3.4.4 Wind Stress....................................................................................................................................18 49 3.4.5 Changes in Surface Waves............................................................................................................19 50 3.4.6 Conclusions...................................................................................................................................20 51 3.5 Changes in Water-Mass Properties and Ventilation...........................................................................20 52 3.5.1 Introduction...................................................................................................................................20 53 3.5.2 North Atlantic Deep Water (NADW) ............................................................................................20 54 3.5.3 North Pacific Intermediate Water (NPIW) and Subtropical Mode Water (STMW) .....................21 55 3.5.4 Southern Ocean.............................................................................................................................21 56 3.5.5 Conclusions...................................................................................................................................22 57 3.6 Changes in Ocean Circulation...............................................................................................................22 Do Not Cite, Quote or Distribute 3-1 Total pages: 89 Second Order Draft Chapter 3 IPCC WGI Fifth Assessment Report 1 3.6.1 Observing Ocean Circulation Variability.....................................................................................22 2 3.6.2 Wind-Driven Circulation Variability in the Pacific Ocean ..........................................................23 3 3.6.3 The Atlantic Meridional Overturning Circulation (AMOC).........................................................24 4 3.6.4 The Antarctic Meridional Overturning Circulation......................................................................26 5 3.6.5 Water Exchange Between Ocean Basins ......................................................................................26 6 3.6.6 Conclusion ....................................................................................................................................27 7 3.7 Sea Level Change, Including Extremes ................................................................................................27 8 3.7.1 Introduction and Overview of Sea Level Measurements ..............................................................27 9 3.7.2 Trends in Global Mean Sea Level and Components.....................................................................28 10 3.7.3 Regional Patterns of Sea Level Change........................................................................................30 11 3.7.4 Observations of Accelerations in GMSL.......................................................................................31 12 3.7.5 Changes in Extreme Sea Level......................................................................................................32 13 3.7.6 Conclusions...................................................................................................................................32 14 3.8 Ocean Biogeochemical Changes, Including Anthropogenic Ocean Acidification ............................34 15 3.8.1 Ocean Carbon...............................................................................................................................34 16 3.8.2 Anthropogenic Ocean Acidification..............................................................................................36 17 Box 3.2: Ocean Acidification .........................................................................................................................37 18 3.8.3 Oxygen ..........................................................................................................................................39 19 3.8.4 Regional and Long-Term Trends in Nutrient Distributions in the Oceans...................................40 20 3.8.5 Summary........................................................................................................................................40 21 3.9 Synthesis ..................................................................................................................................................41 22 FAQ 3.1: Is the Ocean Warming?.................................................................................................................42 23 FAQ 3.2: How Does Anthropogenic Ocean Acidification Relate to Climate Change?............................44 24 FAQ 3.3: Is There Evidence for Changes in the Earth’s Water Cycle?....................................................45 25 References........................................................................................................................................................47 26 Figures .............................................................................................................................................................62 27 28 Do Not Cite, Quote or Distribute 3-2 Total pages: 89 Second Order Draft Chapter 3 IPCC WGI Fifth Assessment Report 1 Executive