Ocean-Atmosphere Interactions of Gases and Particles Springer Earth System Sciences For further volumes: http://www.springer.com/series/10178 Peter S. Liss • Martin T. Johnson Editors Ocean-Atmosphere Interactions of Gases and Particles Editors Peter S. Liss Martin T. Johnson Centre for Ocean and Atmospheric Sciences School of Environmental Sciences University of East Anglia Norwich United Kingdom ISBN 978-3-642-25642-4 ISBN 978-3-642-25643-1 (eBook) DOI 10.1007/978-3-642-25643-1 Springer Heidelberg New York Dordrecht London Library of Congress Control Number: 2013955001 # The Editor(s) (if applicable) and the Author(s) 2014. The book is published with open access at SpringerLink.com. Open Access This book is distributed under the terms of the Creative Commons Attribution Noncommercial License which permits any noncommercial use, distribution, and reproduction in any medium, provided the original author(s) and source are credited. All commercial rights are reserved by the Publisher, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, re-use of illustrations, recitation, broadcasting, reproduction on microfilms or in any other way, and storage in data banks. Duplication of this publication or parts thereof is permitted only under the provisions of the Copyright Law of the Publisher’s location, in its current version, and permission for commercial use must always be obtained from Springer. Permissions for commercial use may be obtained through RightsLink at the Copyright Clearance Center. Violations are liable to prosecution under the respective Copyright Law. Printed on acid-free paper Springer is part of Springer Science+Business Media (www.springer.com) This publication is supported by COST. ESF provides the COST Office through an EC contract COST is supported by the EU RTD Framework programme Preface This book is an outcome and an important part of the legacy of COST Action 735, whose overall aim was to develop tools for estimating air-sea fluxes of compounds important for climate, air quality and ocean productivity. The action was closely allied with the SOLAS (Surface Ocean – Lower Atmosphere Study) project of the International Geosphere-Biosphere Programme (IGBP), with both having very simi- lar objectives. Because of this, they were mutually supportive in many ways. The action ran for 5 years, starting in September 2006 and ending in September 2011. It involved more than 300 scientists mainly from Europe (77 % from the following 18 countries: Belgium, Cyprus, Denmark, Finland, France, Germany, Greece, Hungary, Ireland, Italy, Netherlands, Norway, Poland, Spain, Sweden, Switzerland, Turkey and the United Kingdom) but with a significant number from outside Europe, so that in total scientists from 30 countries participated. One third of the participants were female. The action had a reciprocal agreement with New Zealand. Additional information about the action can be found at http://www.cost-735.org/. The action operated through two types of activity – working group meetings (21 being held in total) and short-term scientific missions, which allowed 19 younger scientists to work in other laboratories in the action. The work of the action was overseen and directed by a Management Committee that met eight times. Many scientific publications have been produced from the work supported by the action; it has also enabled many young scientists working for their Ph.Ds. to broaden their vision and learn techniques not available in their home laboratories. In addition and central to the aims of the action, several important databases have been assem- bled and made available through public data centres. This has in general not involved making new measurements but the gathering together and collating in a coherent format of existing data, much of which was not readily available previously. Notable databases made with support from the action include IRONMAP (atmospheric aerosol iron measurements); HalOcAt (ocean and atmospheric organo-halocarbon data); MEMENTO (marine measurements of methane and nitrous oxide); SOCAT (global surface ocean carbon dioxide database), a comprehensive dimethyl sulphide database, which tripled the previous readily available number of surface ocean measurements; and finally an ongoing effort to assemble measurements of aerosol and rain composition (trace metals and nutrients) made from ships at sea. These various datasets will be an important legacy of the action, and we expect them to prove vital in the future development of the subject. v Given the large amount of research supported by the action, it was decided to produce this book to record the current state of knowledge in the area. Each of the five chapters has several Lead Authors and a larger number of Contributing Authors, using the IPCC authorship model. The Lead Authors together constituted the edito- rial board for the book. Lead authors are identified in the contacts list which follows and by the inclusion of their email addresses at the beginning of each chapter. Each chapter was reviewed by an external reviewer in addition to one member of the editorial board not associated with the chapter. We have tried to have as much consistency of nomenclature and units as possible but have not imposed this where non-standard usage is well established and accepted. Although we have tried to keep redundancy of material between chapters to a minimum, it has not been removed entirely. We consider this is acceptable and even desirable since each chapter can be downloaded independently and so needs to be complete within itself. Topics within each chapter are dealt with in considerable detail and at a research level; so we expect the book to be mainly of interest and constitute a fundamental text for research workers, including graduate students. Many people should be thanked and congratulated for the success of the action and, consequently, for making this book possible. Firstly, thanks are due to the participants in the scientific meetings and members of the Management Committee, as well as the young researchers who took the opportunity to go on short-term scientific missions. The SOLAS office at UEA carried much of the administrative burden of the action, along with COST officers, rapporteurs and the administrative staff. We are grateful to the reviewers of the chapters who made many very useful and perceptive suggestions. Rosie Cullington did a large amount of editorial work on the reference lists for several of the chapters. Kath Mortimer put in a huge and sustained effort at all stages of the production of the book; without her efforts it is unlikely that the project would have been completed. Her thoroughness, excellent planning, persuasiveness and stamina are truly remarkable. We are deeply indebted to all of these people. UEA, Norwich, UK Peter S. Liss COST 735 Chair and Book Editor ICM-CSIC, Barcelona, Spain Rafel Simo ́ COST 735 Vice-Chair UEA, Norwich, UK Martin T. Johnson Book Editor vi Preface Acknowledgments The authors would like to acknowledge the following organisations without whose funding this publication and the meetings which supported this work would not have been possible: • COST Action ES0801: The ocean chemistry of bioactive trace elements and paleoclimate proxies; www.costaction.earth.ox.ac.uk/ • European Cooperation in Science and Technology (COST); www.cost.eu • European Space Agency (ESA); www.esa.int • International Geosphere-Biosphere Programme (IGBP); www.igbp.net • Land-Ocean Interactions in the Coastal Zone (LOICZ); www.loicz.org • Natural Environment Research Council (NERC); www.nerc.ac.uk • Surface Ocean-Lower Atmosphere Study (SOLAS); www.solas-int.org • University of East Anglia (UEA); www.uea.ac.uk vii COST – European Cooperation in Science and Technology COST – European Cooperation in Science and Technology – is an intergovernmental framework aimed at facilitating the collaboration and networking of scientists and researchers at European level. It was established in 1971 by 19 member countries and currently includes 35 member countries across Europe, and Israel as a cooperating state. COST funds pan-European, bottom-up networks of scientists and researchers across all science and technology fields. These networks, called ‘COST Actions’, promote international coordination of nationally-funded research. By fostering the networking of researchers at an international level, COST enables break-through scientific developments leading to new concepts and products, thereby contributing to strengthening Europe’s research and innovation capacities. COST’s mission focuses in particular on: • Building capacity by connecting high-quality scientific communities throughout Europe and worldwide; • Providing networking opportunities for early career investigators; • Increasing the impact of research on policy makers, regulatory bodies and national decision makers as well as the private sector. Through its inclusiveness, COST supports the integration of research communities, leverages national research investments and addresses issues of global relevance. Every year thousands of European scientists benefit from being involved in COST Actions, allowing the pooling of national research funding to achieve common goals. As a precursor of advanced multidisciplinary research, COST anticipates and complements the activities of EU Framework Programmes, constituting a “bridge” towards the scientific communities of emerging countries. In particular, COST Actions are also open to participation by non-European scientists coming from neighbour countries (for example Albania, Algeria, Armenia, Azerbaijan, Belarus, Egypt, Georgia, Jordan, Lebanon, Libya, Moldova, Montenegro, Morocco, the Palestinian Authority, Russia, Syria, Tunisia and Ukraine) and from a number of international partner countries. COST’s budget for networking activities has traditionally been provided by successive EU RTD Framework Programmes. COST is currently executed by the European Science Foundation (ESF) through the COST Office on a mandate by the European Commission, and the framework is governed by a Committee of Senior Officials (CSO) representing all its 35 member countries. More information about COST is available at www.cost.eu. ix Contents 1 Short-Lived Trace Gases in the Surface Ocean and the Atmosphere . . . 1 Peter S. Liss, Christa A. Marandino, Elizabeth E. Dahl, Detlev Helmig, Eric J. Hintsa, Claire Hughes, Martin T. Johnson, Robert M. Moore, John M.C. Plane, Birgit Quack, Hanwant B. Singh, Jacqueline Stefels, Roland von Glasow, and Jonathan Williams 1.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.2 Sulphur and Related Gases . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 1.2.1 DMS(P) in the Surface Ocean . . . . . . . . . . . . . . . . . . . . . . 2 1.2.1.1 Ecosystem Dynamics . . . . . . . . . . . . . . . . . . . . . 2 1.2.1.2 DMS Yield . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 1.2.1.3 Predicted Impact of Climate Change . . . . . . . . . . 3 1.2.2 Other Sulphur and Related Gases in the Surface Ocean . . . 6 1.2.2.1 Carbonyl Sulphide . . . . . . . . . . . . . . . . . . . . . . . 6 1.2.2.2 Carbon Disulphide . . . . . . . . . . . . . . . . . . . . . . . 6 1.2.2.3 Hydrogen Sulphide . . . . . . . . . . . . . . . . . . . . . . . 6 1.2.2.4 Methanethiol . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 1.2.2.5 Dimethyl Selenide . . . . . . . . . . . . . . . . . . . . . . . 7 1.2.3 Atmospheric Sulphur and Related Gases . . . . . . . . . . . . . . 7 1.2.3.1 Chemistry of Sulphur in the Marine Boundary Layer (MBL) . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 1.2.3.2 CLAW Hypothesis . . . . . . . . . . . . . . . . . . . . . . . 11 1.3 Halocarbon Gases . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 1.3.1 Chlorinated Compounds . . . . . . . . . . . . . . . . . . . . . . . . . . 14 1.3.1.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 1.3.1.2 Methyl Chloride . . . . . . . . . . . . . . . . . . . . . . . . . 15 1.3.1.3 Dichloromethane . . . . . . . . . . . . . . . . . . . . . . . . 15 1.3.1.4 Tri- and Tetrachloroethylene . . . . . . . . . . . . . . . . 16 1.3.1.5 Chloroform . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 1.3.2 Brominated Compounds . . . . . . . . . . . . . . . . . . . . . . . . . . 16 1.3.2.1 Methyl Bromide . . . . . . . . . . . . . . . . . . . . . . . . . 16 1.3.2.2 CHBr 3 , CH 2 Br 2 and Other Polybrominated Methanes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 1.3.3 Iodinated Compounds . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 1.3.3.1 Iodomethane . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 1.3.3.2 Other Mono-Iodinated Iodocarbons . . . . . . . . . . . 20 1.3.3.3 Di- and Tri-Halogenated Compounds . . . . . . . . . 20 1.3.4 Halogens in the Marine Atmospheric Boundary Layer . . . . 21 xi 1.4 Non-Methane Hydrocarbons (NMHCs) . . . . . . . . . . . . . . . . . . . . 26 1.4.1 Oxygenated Volatile Organic Compounds (OVOCs) . . . . . 26 1.4.1.1 Atmospheric Importance of OVOCs . . . . . . . . . . 26 1.4.1.2 Atmospheric Budget . . . . . . . . . . . . . . . . . . . . . . 27 1.4.1.3 Surface Ocean Processes . . . . . . . . . . . . . . . . . . 29 1.4.2 Alkanes and Alkenes . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 1.4.3 Alkyl Nitrates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 1.4.4 Hydrogen Cyanide (HCN) and Methyl Cyanide (CH 3 CN) . . . . 33 1.5 Ozone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 1.6 Nitric Oxide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 1.7 Ammonia and Amines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 1.7.1 Ammonia . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 1.7.2 Amines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 1.8 Hydrogen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 1.9 Carbon Monoxide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 1.10 Concluding Remarks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 2 Transfer Across the Air-Sea Interface . . . . . . . . . . . . . . . . . . . . . . . . 55 Christoph S. Garbe, Anna Rutgersson, Jacqueline Boutin, Gerrit de Leeuw, Bruno Delille, Christopher W. Fairall, Nicolas Gruber, Jeffrey Hare, David T. Ho, Martin T. Johnson, Philip D. Nightingale, Heidi Pettersson, Jacek Piskozub, Erik Sahle ́e, Wu-ting Tsai, Brian Ward, David K. Woolf, and Christopher J. Zappa 2.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 2.2 Processes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56 2.2.1 Microscale Wave Breaking . . . . . . . . . . . . . . . . . . . . . . . . 56 2.2.2 Small Scale Turbulence . . . . . . . . . . . . . . . . . . . . . . . . . . 60 2.2.3 Bubbles, Sea Spray . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61 2.2.4 Wind-Generated Waves . . . . . . . . . . . . . . . . . . . . . . . . . . 65 2.2.5 Large-Scale Turbulence . . . . . . . . . . . . . . . . . . . . . . . . . . 66 2.2.6 Rain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67 2.2.7 Surface Films . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68 2.2.8 Biological and Chemical Enhancement . . . . . . . . . . . . . . . 69 2.2.9 Atmospheric Processes . . . . . . . . . . . . . . . . . . . . . . . . . . . 70 2.3 Process Models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72 2.3.1 Interfacial Models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72 2.3.1.1 Thin (Stagnant) Film Model . . . . . . . . . . . . . . . . 72 2.3.1.2 Surface Renewal Model . . . . . . . . . . . . . . . . . . . 73 2.3.1.3 Eddy Renewal Model . . . . . . . . . . . . . . . . . . . . . 73 2.3.1.4 Surface Penetration . . . . . . . . . . . . . . . . . . . . . . 73 2.3.1.5 Air-Side Transfer . . . . . . . . . . . . . . . . . . . . . . . . 74 2.3.2 Direct Numerical Simulations (DNS) and Large Eddy Simulations (LES) . . . . . . . . . . . . . . . . . . . . . . . . . . 74 2.4 Exchanged Quantities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76 2.4.1 Physical Quantities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76 2.4.2 Gases . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76 xii Contents 2.4.3 Particles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78 2.4.3.1 Dry Deposition . . . . . . . . . . . . . . . . . . . . . . . . . 78 2.4.3.2 Wet Deposition . . . . . . . . . . . . . . . . . . . . . . . . . 79 2.5 Measurement Techniques . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80 2.5.1 Small-Scale Measurements Techniques . . . . . . . . . . . . . . . 80 2.5.1.1 Particle-Based Techniques . . . . . . . . . . . . . . . . . 80 2.5.1.2 Thermographic Techniques . . . . . . . . . . . . . . . . . 81 2.5.2 Micrometeorological Techniques . . . . . . . . . . . . . . . . . . . 81 2.5.3 Mass Balance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83 2.5.3.1 Techniques . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83 2.5.3.2 Scales (Spatial and Temporal) . . . . . . . . . . . . . . . 84 2.5.3.3 Accuracy and Limitations . . . . . . . . . . . . . . . . . . 84 2.5.3.4 Current and Recent Field Studies . . . . . . . . . . . . 84 2.5.4 Profiles of pCO 2 Near the Surface . . . . . . . . . . . . . . . . . . . 85 2.5.5 Method Evaluation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85 2.6 Parameterization of Gas Exchange . . . . . . . . . . . . . . . . . . . . . . . . 87 2.6.1 Wind Speed Relationships . . . . . . . . . . . . . . . . . . . . . . . . 87 2.6.2 Surface Roughness, Slope . . . . . . . . . . . . . . . . . . . . . . . . 90 2.6.3 NOAA-COARE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90 2.6.4 Energy Dissipation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92 2.6.5 Evaluating and Selecting Transfer Velocity Parameterisations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93 2.7 Sea Ice . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95 2.8 Applications of Air-Sea Gas Transfer . . . . . . . . . . . . . . . . . . . . . . 96 2.8.1 Models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97 2.8.2 Remote Sensing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99 2.8.3 Inventories, Climatologies Using In Situ Data . . . . . . . . . . 100 2.9 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102 3 Air-Sea Interactions of Natural Long-Lived Greenhouse Gases (CO 2 , N 2 O, CH 4 ) in a Changing Climate . . . . . . . . . . . . . . . . . 113 Dorothee C.E. Bakker, Hermann W. Bange, Nicolas Gruber, Truls Johannessen, Rob C. Upstill-Goddard, Alberto V. Borges, Bruno Delille, Carolin R. Lo ̈scher, S. Wajih A. Naqvi, Abdirahman M. Omar, and J. Magdalena Santana-Casiano 3.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113 3.1.1 Atmospheric Greenhouse Gases from Ice Cores . . . . . . . . . . 116 3.2 Surface Ocean Distribution and Air-Sea Exchange of CO 2 . . . . . . . 117 3.2.1 Global Tropospheric CO 2 Budget . . . . . . . . . . . . . . . . . . . . 117 3.2.2 Processes Controlling CO 2 Dynamics in the Upper Water Column . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117 3.2.3 Surface Ocean fCO 2 and Air-Sea CO 2 Fluxes in the Open Ocean . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121 3.2.3.1 Surface Ocean fCO 2 Distribution . . . . . . . . . . . . . 121 3.2.3.2 Multi-Year Changes and Trends . . . . . . . . . . . . . . 123 3.2.3.3 Comparison of Air-Sea CO 2 Flux Estimates . . . . . 124 3.2.3.4 Sea Ice . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125 3.2.3.5 Coastal to Open Ocean Carbon Exchanges . . . . . . 126 Contents xiii 3.2.4 Air-Sea CO 2 Fluxes in Coastal Areas . . . . . . . . . . . . . . . . . 126 3.2.4.1 Continental Shelves . . . . . . . . . . . . . . . . . . . . . . . 126 3.2.4.2 Near-Shore Systems . . . . . . . . . . . . . . . . . . . . . . . 129 3.2.4.3 Multi-Year Changes and Trends . . . . . . . . . . . . . . 129 3.3 Marine Distribution and Air-Sea Exchange of N 2 O . . . . . . . . . . . . . 130 3.3.1 Global Tropospheric N 2 O Budget . . . . . . . . . . . . . . . . . . . . 130 3.3.2 Nitrous Oxide Formation Processes . . . . . . . . . . . . . . . . . . 130 3.3.2.1 Denitrification . . . . . . . . . . . . . . . . . . . . . . . . . . . 130 3.3.2.2 Nitrification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131 3.3.2.3 N 2 O Formation by Dissimilatory Nitrate Reduction to Ammonium . . . . . . . . . . . . . . . . . . . 132 3.3.3 Global Oceanic Distribution of Nitrous Oxide . . . . . . . . . . . 132 3.3.4 Coastal Distribution of Nitrous Oxide . . . . . . . . . . . . . . . . . 134 3.3.5 Marine Emissions of Nitrous Oxide . . . . . . . . . . . . . . . . . . 135 3.4 Marine Distribution and Air-Sea Exchange of CH 4 . . . . . . . . . . . . . 137 3.4.1 Global Tropospheric CH 4 Budget . . . . . . . . . . . . . . . . . . . . 137 3.4.2 Formation and Removal Processes for Methane . . . . . . . . . . 137 3.4.3 Global Oceanic Distribution of Methane . . . . . . . . . . . . . . . 139 3.4.4 Coastal Distribution of Methane . . . . . . . . . . . . . . . . . . . . . 139 3.4.4.1 Coastal Sediments . . . . . . . . . . . . . . . . . . . . . . . . 139 3.4.4.2 Coastal Waters . . . . . . . . . . . . . . . . . . . . . . . . . . . 142 3.4.4.3 Methane Hydrates . . . . . . . . . . . . . . . . . . . . . . . . 143 3.4.5 Marine Emissions of Methane . . . . . . . . . . . . . . . . . . . . . . 146 3.5 Impact of Global Change . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147 3.5.1 Future Changes in the Physics of the Oceanic Surface Layer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147 3.5.1.1 Carbon Dioxide in the Open Ocean . . . . . . . . . . . . 147 3.5.1.2 Carbon Dioxide in Coastal Seas . . . . . . . . . . . . . . 149 3.5.1.3 Nitrous Oxide and Methane . . . . . . . . . . . . . . . . . 150 3.5.2 Ocean Acidification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150 3.5.2.1 Carbon Dioxide . . . . . . . . . . . . . . . . . . . . . . . . . . 150 3.5.2.2 Nitrous Oxide and Methane . . . . . . . . . . . . . . . . . 152 3.5.3 Deoxygenation and Suboxia in the Open Ocean . . . . . . . . . 152 3.5.4 Coastal Euthrophication and Hypoxia . . . . . . . . . . . . . . . . . 153 3.5.5 Changes in Methane Hydrates . . . . . . . . . . . . . . . . . . . . . . 153 3.6 Key Uncertainties in the Air-Sea Transfer of CO 2 , N 2 O and CH 4 . . . 154 3.6.1 Outgassing of Riverine Carbon Inputs . . . . . . . . . . . . . . . . . 154 3.6.2 Heterogeneity in Coastal Systems . . . . . . . . . . . . . . . . . . . . 155 3.6.3 Sea Ice . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155 3.6.4 Parameterising Air-Sea Gas Transfer . . . . . . . . . . . . . . . . . 155 3.6.5 Data Collection, Data Quality and Data Synthesis . . . . . . . . 155 3.7 Conclusions and Outlook . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156 3.7.1 Carbon Dioxide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156 3.7.2 Nitrous Oxide and Methane . . . . . . . . . . . . . . . . . . . . . . . . 156 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157 xiv Contents 4 Ocean–Atmosphere Interactions of Particles . . . . . . . . . . . . . . . . . . . 171 Gerrit de Leeuw, Ce ́cile Guieu, Almuth Arneth, Nicolas Bellouin, Laurent Bopp, Philip W. Boyd, Hugo A.C. Denier van der Gon, Karine V. Desboeufs, Franc ̧ois Dulac, M. Cristina Facchini, Brett Gantt, Baerbel Langmann, Natalie M. Mahowald, Emilio Maran ̃o ́n, Colin O’Dowd, Nazli Olgun, Elvira Pulido-Villena, Matteo Rinaldi, Euripides G. Stephanou, and Thibaut Wagener 4.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 171 4.2 Aerosol Production and Transport in the Marine Atmosphere . . . . . 174 4.2.1 Sources of Aerosol in the Marine Atmosphere . . . . . . . . . . . 174 4.2.1.1 Sea Spray Aerosol Production . . . . . . . . . . . . . . . . 174 4.2.1.2 Organic Enrichment of Particulate Organic Matter in Sea Spray Aerosol . . . . . . . . . . . . . . . . . 176 Laboratory Studies . . . . . . . . . . . . . . . . . . . . . . . . 179 Global Distribution of Organic Enrichment . . . . . . 180 4.2.1.3 Secondary Aerosol Formation in the Marine Atmospheric Boundary Layer . . . . . . . . . . . . . . . . 182 Secondary Inorganic Aerosol Formation . . . . . . . . 182 Secondary Organic Marine Aerosol . . . . . . . . . . . 183 New Particle Formation in the Marine Boundary Layer? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 184 4.2.2 Non-Marine Sources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 186 4.2.2.1 Desert Dust . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 186 4.2.2.2 Volcanic Gases, Aerosols and Ash . . . . . . . . . . . . 189 4.2.2.3 Global Emissions of Biogenic Volatile Organis Compounds (BVOC’s) from Terrestrial Ecosystems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 191 4.2.2.4 Anthropogenic Emissions . . . . . . . . . . . . . . . . . . . 193 Anthropogenic Land-Based Emissions . . . . . . . . . 193 Uncertainty in Global Anthropogenic Emissions . . . 193 Global Biomass Burning Emissions . . . . . . . . . . . 194 International Shipping Emissions . . . . . . . . . . . . . 194 Comparison and Evaluation of Different Emission Datasets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 195 4.2.3 Ageing and Mixing of Aerosols During Transport . . . . . . . . 196 4.2.3.1 Chemical Ageing of Organic Aerosols . . . . . . . . . 196 4.2.3.2 Internal Mixing . . . . . . . . . . . . . . . . . . . . . . . . . . 197 Dust/Inorganic Species . . . . . . . . . . . . . . . . . . . . . 197 Dust/Organic Species . . . . . . . . . . . . . . . . . . . . . . 198 Sea Salt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 200 Future Directions . . . . . . . . . . . . . . . . . . . . . . . . . 200 4.2.4 Dust-Mediated Transport of Living Organisms and Pollutants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 201 4.3 Direct Radiative Effects (DRE) . . . . . . . . . . . . . . . . . . . . . . . . . . . 202 4.4 Effects on Cloud Formation and Indirect Radiative Effects . . . . . . . 204 4.5 Deposition of Aerosol Particles to the Ocean Surface and Impacts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 206 Contents xv 4.5.1 Deposition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 206 4.5.1.1 Iron . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 206 4.5.1.2 Phosphorus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 207 4.5.1.3 Nitrogen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 209 4.5.1.4 Deposition of Other Species . . . . . . . . . . . . . . . . . 209 4.5.2 Elements of Biogeochemical Interest and Their Chemical Forms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 209 4.5.3 Dissolution- Scavenging Processes . . . . . . . . . . . . . . . . . . . 211 4.5.4 Atmospheric Impacts in HNLC and LNLC Areas . . . . . . . . 213 4.5.4.1 Experimental: Large Scale Fertilisation Experiments (Fe, P) . . . . . . . . . . . . . . . . . . . . . . . 213 4.5.4.2 Experimental: Microcosms . . . . . . . . . . . . . . . . . . 215 Main Results Obtained from the Microcosm Approach . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215 4.5.4.3 Experimental: In Situ Mesocosms . . . . . . . . . . . . . 218 4.5.4.4 Modelling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 221 4.5.5 Particulate Matter and Carbon Export . . . . . . . . . . . . . . . . . 222 4.6 Summary and Outlook . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 224 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 227 5 Perspectives and Integration in SOLAS Science . . . . . . . . . . . . . . . . . 247 Ve ́ronique C. Garc ̧on, Thomas G. Bell, Douglas Wallace, Steve R. Arnold, Alex Baker, Dorothee C.E. Bakker, Hermann W. Bange, Nicholas R. Bates, Laurent Bopp, Jacqueline Boutin, Philip W. Boyd, Astrid Bracher, John P. Burrows, Lucy J. Carpenter, Gerrit de Leeuw, Katja Fennel, Jordi Font, Tobias Friedrich, Christoph S. Garbe, Nicolas Gruber, Lyatt Jaegle ́, Arancha Lana, James D. Lee, Peter S. Liss, Lisa A. Miller, Nazli Olgun, Are Olsen, Benjamin Pfeil, Birgit Quack, Katie A. Read, Nicolas Reul, Christian Ro ̈denbeck, Shital S. Rohekar, Alfonso Saiz-Lopez, Eric S. Saltzman, Oliver Schneising, Ute Schuster, Roland Seferian, Tobias Steinhoff, Pierre-Yves Le Traon, and Franziska Ziska 5.1 Perspectives: In Situ Observations, Remote Sensing, Modelling and Synthesis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 248 5.1.1 In Situ Observations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 248 5.1.1.1 ARGO (T, S, O 2 ) . . . . . . . . . . . . . . . . . . . . . . . . . 248 5.1.1.2 Ocean Observatories . . . . . . . . . . . . . . . . . . . . . . 250 5.1.1.3 Atmospheric Observatories . . . . . . . . . . . . . . . . . . 250 5.1.1.4 Monitoring Reactive Trace Species in the Marine Atmosphere: Highlights from the Cape Verde Observatory . . . . . . . . . . . . . . . . . . . . . . . . 251 5.1.1.5 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 255 5.1.2 Earth Observation Products . . . . . . . . . . . . . . . . . . . . . . . . 255 5.1.2.1 Altimetry, SST, Winds, Sea State . . . . . . . . . . . . . 256 5.1.2.2 Sea Surface Salinity . . . . . . . . . . . . . . . . . . . . . . . 260 5.1.2.3 Marine Carbon Observations from Satellite Data: Ocean Color/PIC/POC . . . . . . . . . . . . . . . . . . . . . 261 5.1.2.4 Sea Ice . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 264 5.1.2.5 Aerosols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 266 xvi Contents 5.1.2.6 Satellite Measurements of Trace Gases Over the Oceans . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 267 5.1.2.7 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 270 5.1.3 Modelling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 270 5.1.3.1 Global Perspective, Prognostic IPCC and Hindcast . . . . . . . . . . . . . . . . . . . . . . . . . . . . 271 5.1.3.2 Regional Perspectives from High-Resolution Modeling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 272 5.1.3.3 Inverse Modelling . . . . . . . . . . . . . . . . . . . . . . . . 274 5.1.3.4 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 275 5.1.4 SOLAS/COST Data Synthesis Efforts . . . . . . . . . . . . . . . . . 276 5.1.4.1 MEMENTO (MarinE MethanE and NiTrous Oxide) Database . . . . . . . . . . . . . . . . . . . 276 5.1.4.2 HalOcAt (Halocarbons in the Ocean and Atmosphere) . . . . . . . . . . . . . . . . . . . . . . . . . 276 5.1.4.3 DMS-GO (DMS in the Global Ocean) . . . . . . . . . . 278 5.1.4.4 The Surface Ocean CO 2 ATlas (SOCAT) . . . . . . . 279 5.1.4.5 Aerosol and Rainwater Chemistry Database . . . . . 280 5.1.4.6 A Data Compilation of Iron Addition Experiments . . . . . . . . . . . . . . . . . . . . . . . . . . . . 281 5.1.4.7 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 283 5.2 Examples of SOLAS Integrative Studies . . . . . . . . . . . . . . . . . . . . 284 5.2.1 DMS Ocean Climatology and DMS Marine Modelling . . . . 284 5.2.1.1 Global Climatologies Based on Observations . . . . . 284 5.2.1.2 Diagnostic Approaches: Based on Empirical Correlations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 284 5.2.1.3 Prognostic Modelling: From 1D to 3D . . . . . . . . . 284 5.2.1.4 Examples of Applications . . . . . . . . . . . . . . . . . . . 286 Climate Change . . . . . . . . . . . . . . . . . . . . . . . . . . 286 Iron Fertilisation . . . . . . . . . . . . . . . . . . . . . . . . . 286 5.2.2 North Pacific Volcanic Ash and Ecosystem Response . . . . . 287 5.2.3 CO 2 in the North Atlantic . . . . . . . . . . . . . . . . . . . . . . . . . . 289 5.2.4 Global Distribution of Sea Salt Aerosols . . . . . . . . . . . . . . . 292 5.3 Perspectives for the Future . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 293 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 294 Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 307 Contents xvii Contributors Almut Arneth is Professor and Head of Division of Ecosystem-Atmosphere Interactions at the Karlsruhe Insti- tute of Technology, Institute of Meteorology and Climate Research/Atmospheric Environmental Research. Her research interests are in the interactions of climate change, land use change, vegetation dynamics and terrestrial bio- geochemical cycles, and the feedbacks existing in that system. Steve Arnold is a Senior Lecturer in the School of Earth and Environment at the University of Leeds. His research interests are in the chemistry of the lower atmosphere and interactions between air quality, climate and the biosphere. xix