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The use of optical methodology, instrumentation and photonics devices for imaging, vision and optical sensing is of increasing importance in understanding our marine environment. Subsea optics can make an important contribution to the protection and sustainable management of ocean resources and contribute to monitoring the response of marine systems to climate change. This important book provides an authoritative review of key principles, technologies and their applications.The book is divided into three parts. The first part provides a general introduction to the key concepts in subsea optics and imaging, imaging technologies and the development of ocean optics and colour analysis. Part two reviews the use of subsea optics in environmental analysis. An introduction to the concepts of underwater light fields is followed by an overview of coloured dissolved organic matter (CDOM) and an assessment of nutrients in the water column. This section concludes with discussions of the properties of subsea bioluminescence, harmful algal blooms and their impact and finally an outline of optical techniques for studying suspended sediments, turbulence and mixing in the marine environment. Part three reviews subsea optical systems technologies. A general overview of imaging and visualisation using conventional photography and video leads onto advanced techniques like digital holography, laser line-scanning and range-gated imaging as well as their use in controlled observation platforms or global observation networks. This section also outlines techniques like Raman spectroscopy, hyperspectral sensing and imaging, laser Doppler anemometry (LDA) and particle image velocimetry (PIV), optical fibre sensing and LIDAR systems. Finally, a chapter on fluorescence methodologies brings the volume to a close.With its distinguished editor and international team of contributors, Subsea optics and imaging is a standard reference for those researching, developing and using subsea optical technologies as well as environmental scientists and agencies concerned with monitoring the marine environment.Provides an authoritative review of key principles, technologies and their applicationsOutlines the key concepts in subsea optics and imaging, imaging technologies and the development of ocean optics and colour analysisReviews the properties of subsea bioluminescence, harmful algal blooms and their impact

Optical remote sensing is of invaluable help in understanding the marine environment and its biogeochemical and physical processes. The Coastal Zone Color Scanner (CZCS), which operated on board the Nimbus-7 satellite from late 1978 to early 1986, has been the main source of ocean colour data. Much work has been devoted to CZCS data processing and analysis techniques throughout the 1980s. After a decade of experience, the Productivity of the Global Ocean (PGO) Activity - which was established in the framework of the International Space Year 1992 (ISY'92) by SAFISY, the Space Agency Forum of ISY - sponsored a workshop aimed at providing a reference in ocean colour science and at promoting the full exploitation of the CZCS historical data in the field of biological oceanography. The present volume comprises a series of state-of-the-art contributions on theory, applications and future perspectives of ocean colour. After an introduction on the historical perspective of ocean colour, a number of articles are devoted to the CZCS theoretical background, on radiative transfer and in-water topics, as well as on calibration, atmospheric correction and pigment concentration retrieval algorithms developed for the CZCS. Further, a review is given of major applications of CZCS data around the world, carried out in the past decade. The following part of the book is centered on the application of ocean colour to the assessment of marine biological information, with particular regard to plankton biomass, primary productivity and the coupling of physical/biological models. The links between global oceanic production and climate dynamics are also addressed. Finally, the last section is devoted to future approaches and goals of ocean colour science, and to planned sensors and systems. The book is required reading for those involved in ocean colour and related disciplines, providing an overview of the current status in this field as well as stimulating thedebate on new ideas and developments for upcoming ocean colour missions.

Since the pioneering work of Clarke et a1. (1970) it has been known that chlorophyll a (or. more generally. pigments) contained in phytoplankton in near-surface waters produced systematic variations in the color of the ocean which could be observed from aircraft. As a direct result of this work. NASA developed the Coastal Zone Color Scanner (CZCS). which was launched on Nimbus-G (now Nimbus-7) in October 1978. (A short description of the CZCS is provided in Appendix I.) Shortly before launch. at the IUCRM Colloquium on Passive Radiometry of the Ocean (June 1978). a working group on water color measurements was formed to assess water color remote sensing at that time. A report (Morel and Gordon. 1980) was prepared which summarized the state-of-the-art of the algorithms for atmospheric correction. and phytoplankton pigment and seston retrieval. and which included recommendations concerning the design of next generation sensors. The water color session of the COSPAR/SCOR/IUCRM Symposium'Oceanography from Space'held in Venice (May 1980. i. e •• in the post-launch period) provided the opportunity for a reassessment of the state-of-the-art after having gained some experience in the analysis of the initial CZCS imagery. Such an assessment is the purpose of this review paper. which will begin with an outline of the basic physics of water color remote sensing and the fundamentals of atmospheric corrections. The present state of the constituent retrieval and atmospheric correction algorithms will then be critically assessed.

The ocean is a fundamental component of the earth's biosphere. It covers roughly 70 percent of Earth's surface and plays a pivotal role in the cycling of life's building blocks, such as nitrogen, carbon, oxygen, and sulfur. The ocean also contributes to regulating the climate system. Most of the primary producers in the ocean comprise of microscopic plants and some bacteria; and these photosynthetic organisms (phytoplankton) form the base of the ocean's food web. Monitoring the health of the ocean and its productivity is critical to understanding and managing the ocean's essential functions and living resources. Because the ocean is so vast and difficult for humans to explore, satellite remote sensing of ocean color is currently the only way to observe and monitor the biological state of the surface ocean globally on time scales of days to decades. Ocean color measurements reveal a wealth of ecologically important characteristics including: chlorophyll concentration, the rate of phytoplankton photosynthesis, sediment transport, dispersion of pollutants, and responses of oceanic biota to long-term climate changes. Continuity of satellite ocean color data and associated climate research products are presently at significant risk for the U.S. ocean color community. Assessing Requirements for Sustained Ocean Color Research and Operations aims to identify the ocean color data needs for a broad range of end users, develop a consensus for the minimum requirements, and outline options to meet these needs on a sustained basis. The report assesses lessons learned in global ocean color remote sensing from the SeaWiFS/MODIS era to guide planning for acquisition of future global ocean color radiance data to support U.S. research and operational needs.

Princess Enheduanna, daughter of king Sargon of Akkad, lived around 2300 BC. She was a high priestess of the moon god Nanna in the ancient city of Ur. And an accomplished poet too. In fact, she is the author of a number of Sumerian hymns, and is generally considered to be the earliest author known by name. When she came to honor Inanna – the goddess of sexual love, fertility, and warfare, daughter of Nanna and often associated with the planet Venus (the one that the Akkadians called Ishtar) – above all the other gods of the Sumerian pantheon, she mentioned for the very first time, in her Hymn number 8, nothing less than the “Seven Seas”... Septem Maria, would call them the Romans centuries later, after inher- ing the concept from the Greeks (for whom seven probably just meant several), but perhaps applying it to the wrong place – i. e. the extensive system of coastal lagoons, which at the time dotted the northern Adriatic Sea – at least in the description of Pliny the Elder, Roman fleet commander and scholarly author of Historia Naturalis. Indeed, which seven seas are int- ded depends on the context. According to the historians, there are at least nine bodies of water in the medieval European and Arabic literature that can - pire to qualify as one of the famous seven.