The Changing Ocean Carbon Cycle

The world's oceans act as a reservoir, with the capacity to absorb and retain carbon dioxide. The air-sea exchange of carbon is driven by physico-chemical forces, photosynthesis, and respiration, and has an important influence on atmospheric composition. Variability in the ocean carbon cycle could therefore exert significant feedback effects during conditions of climate change. The Joint Global Ocean Flux Study (JGOFS) is the first multidisciplinary program to directly address the interactions among the biology, chemistry, and physics of marine systems, with emphasis on the transport and transformations of carbon within the ocean and across its boundaries. This unique volume, written by an international panel of scientists, provides a synthesis of JGOFS science and its achievements to date. The authoritative chapters will be of great interest to readers seeking a current overview of the role of ocean processes in Earth system science and their wider implications for climate change.

Oceans account for 50% of the anthropogenic CO2 released into the atmosphere. During the past 15 years an international programme, the Joint Global Ocean Flux Study (JGOFS), has been studying the ocean carbon cycle to quantify and model the biological and physical processes whereby CO2 is pumped from the ocean's surface to the depths of the ocean, where it can remain for hundreds of years. This project is one of the largest multi-disciplinary studies of the oceans ever carried out and this book synthesises the results. It covers all aspects of the topic ranging from air-sea exchange with CO2, the role of physical mixing, the uptake of CO2 by marine algae, the fluxes of carbon and nitrogen through the marine food chain to the subsequent export of carbon to the depths of the ocean. Special emphasis is laid on predicting future climatic change.

Our desire to understand the global carbon cycle and its link to the climate system represents a huge challenge. These overarching questions have driven a great deal of scientific endeavour in recent years: What are the basic oceanic mechanisms which control the oceanic carbon reservoirs and the partitioning of carbon between ocean and atmosphere? How do these mechanisms depend on the state of the climate system and how does the carbon cycle feed back on climate? What is the current rate at which fossil fuel carbon dioxide is absorbed by the oceans and how might this change in the future? To begin to answer these questions we must first understand the distribution of carbon in the ocean, its partitioning between different ocean reservoirs (the "solubility" and "biological" pumps of carbon), the mechanisms controlling these reservoirs, and the relationship of the significant physical and biological processes to the physical environment. The recent surveys from the JGOFS and WOCE (Joint Global Ocean Flux Study and World Ocean Circulation Ex periment) programs have given us a first truly global survey of the physical and biogeochemical properties of the ocean. These new, high quality data provide the opportunity to better quantify the present oceans reservoirs of carbon and the changes due to fossil fuel burning. In addition, diverse process studies and time-series observations have clearly revealed the complexity of interactions between nutrient cycles, ecosystems, the carbon-cycle and the physical envi ronment.

A comprehensive progress report on the multi-disciplinary field of ocean and climate change research is given. It compiles introductory background papers and leading scientific results on the ocean-atmosphere carbon cycle with emphasis on the ocean's carbon inventory and the various components involved. The relationship between plankton productivity, carbon fixation, oceanic PCO2 and climate change is investigated from the viewpoint of long-term climatic change during the late Quaternary cycles of ice ages and warm ages. The various approaches range from micropaleontology over organic and trace element geochemistry to molecular isotope geochemistry.

This title includes a number of Open Access chapters. This valuable compendium provides an overview of the variables and consequences of oceanic carbon cycling in the context of climate change. The chapters highlight the importance of marine plankton in carbon processing as well as the effects of rising CO2 and temperature in their functioning. Marine ecosystems are being increasingly threatened by growing human pressures, including climate change. Understanding the consequences that climate change may have is crucial to predict the future of our oceans. Rising temperatures and ocean acidification may profoundly alter the mode of matter and energy transformation in marine ecosystems, which could have irreversible consequences for our planet on ecological timescales. For that reason, the scientific community has engaged in the grand challenge of studying the variables and consequences of oceanic carbon cycling in the context of climate change, which has emerged as a relevant field of science. The book is broken into four sections: Understanding the Importance of Ocean Biogeochemistry Quantifying Oceanic Carbon Variables Phytoplankton and Oceanic Carbon Cycle Ocean Acidification Edited by a researcher with many years of experience and with contributions from scientists from around the world, this volume explores the most important topics on climate change and oceanic carbon cycling.

While a number of gases are implicated in global warming, carbon dioxide is the most important contributor, and in one sense the entire phenomena can be seen as a human-induced perturbation of the carbon cycle. The Global Carbon Cycle offers a scientific assessment of the state of current knowledge of the carbon cycle by the world's leading scientists sponsored by SCOPE and the Global Carbon Project, and other international partners. It gives an introductory over-view of the carbon cycle, with multidisciplinary contributions covering biological, physical, and social science aspects. Included are 29 chapters covering topics including: an assessment of carbon-climate-human interactions; a portfolio of carbon management options; spatial and temporal distribution of sources and sinks of carbon dioxide; socio-economic driving forces of emissions scenarios. Throughout, contributors emphasize that all parts of the carbon cycle are interrelated, and only by developing a framework that considers the full set of feedbacks will we be able to achieve a thorough understanding and develop effective management strategies. The Global Carbon Cycle edited by Christopher B. Field and Michael R. Raupach is part of the Rapid Assessment Publication series produced by the Scientific Committee on Problems of the Environment (SCOPE), in an effort to quickly disseminate the collective knowledge of the world's leading experts on topics of pressing environmental concern.

Marine geochemistry uses chemical elements and their isotopes to study how the ocean works in terms of ocean circulation, chemical composition, biological activity and atmospheric CO2 regulation. This rapidly growing field is at a crossroad for many disciplines (physical, chemical and biological oceanography, geology, climatology, ecology, etc.). It provides important quantitative answers to questions such as: What is the deep ocean mixing rate? How much atmospheric CO2 is pumped by the ocean? How fast are pollutants removed from the ocean? How do ecosystems react to anthropogenic pressure? This text gives a simple introduction to the concepts, the methods and the applications of marine geochemistry with a particular emphasis on isotopic tracers. Overall introducing a very large number of topics (physical oceanography, ocean chemistry, isotopes, gas exchange, modelling, biogeochemical cycles), with a balance of didactic and indepth information, it provides an outline and a complete course in marine geochemistry. Throughout, the book uses a hands-on approach with worked out exercises and problems (with answers provided at the end of the book), to help the students work through the concepts presented. A broad scale approach is take including ocean physics, marine biology, ocean-climate relations, remote sensing, pollutions and ecology, so that the reader acquires a global perspective of the ocean. It also includes new topics arising from ongoing research programs. This textbook is essential reading for students, scholars, researchers and other professionals.