"In the history of humankind, the sea has always played a key role as a privileged medium for communication, commerce and contact among population centers. It constitutes an essential ecosystem, and an invaluable reservoir and source of food for all living beings. Therefore, its heath is a critical challenge for the survival of all humanity, particularly as one the most important environmental components targeted by global warming. Measuring and monitoring techniques are key tools for managing the marine environment and for supporting the Blue Economy. With this perspective, a series of annual international events, entitled Metrology for the Sea (MetroSea for short) was begun in 2017. Their increasing success inspired this book, which provides an anthology of tutorials dealing with a representative selection of topics of concern to a broad readership.

 The book covers two broad application areas, marine hydrography and meteorology, and then deals with instrumentation for measurement at sea. Typical metrological issues such as calibration and traceability, are considered, for both physical and chemical quantities. Key techniques, such as underwater acoustic investigation, remote sensing, measurement of waves and monitoring networks, are treated alongside marine geology and the monitoring of animal species. Economic and legal aspects of metrology for navigation are also discussed. Such an unparalleled wide vision of measurement for the sea will be of interest to a broad audience of scientists, engineers, economists, and their students..

Table of contents :
Chapter 1: Hydrography: From Marine Data to Information 1.1 Hydrography: An Applied Science 1.2 4D Reference Frame 1.2.1 The Measure 1.2.2 The Reference 1.2.3 4D Reference Frame 1.2.3.1 The Instrumental Reference Frame 1.2.3.2 Among the Instruments and the Results: The Body Frame 1.2.3.3 The Position Reference Frame 1.2.3.4 The Vertical Reference Frame 1.2.3.5 The Time Reference Frame 1.3 The Hydrographic Measures 1.3.1 The Positioning 1.3.2 The Attitude 1.3.3 The Depth 1.3.3.1 The Singlebeam Echosounder (SBES) 1.3.3.2 The Multibeam Echosounder (MBES) 1.3.3.3 The Airborne Lidar Bathymetry (ALB) 1.4 The Hydrographic Standards 1.4.1 The IHO Standard 1.5 From Marine Data to Information 1.5.1 Data Processing 1.5.2 From Data to Marine Spatial Data Infrastructures 1.5.3 A Look into the Future References Chapter 2: Measurements for Meteorology 2.1 Introduction 2.2 Organization of Marine Meteorological Services 2.3 Weather Observations from Ships 2.3.1 Automatic Weather Stations (AWS) 2.3.2 Radio Soundings 2.4 Ocean-Atmosphere Heat Fluxes 2.5 Observations from Buoys 2.5.1 Moored Buoys 2.5.1.1 Anemometers 2.5.1.2 Barometers 2.5.1.3 Air-Temperature Sensors 2.5.1.4 Solar Radiation 2.5.1.5 Relative Humidity 2.5.1.6 Precipitation 2.5.1.7 Power Source and Data Management 2.5.2 Drifting Buoys 2.6 Future Developments References Chapter 3: Measurements for Oceanography 3.1 Introduction 3.2 Thermohaline Measurements from Ship 3.2.1 CTD and Rosette 3.2.2 Vertical Profiles Collected from a Moving Vessel: XBT, XCTD, Underway CTD, and Their Evolution 3.3 Current Measurement 3.3.1 Lagrangian Instruments 3.3.2 Eulerian Oceanographic Observations: Moorings 3.4 Unmanned Vehicles 3.4.1 Floats 3.4.2 Glider and Wave Glider References Chapter 4: Metrology for the Sea: Physical Quantities 4.1 Temperature 4.1.1 Temperature: A Physical Quantity 4.1.2 The International Temperature Scale of 1990 or ITS-90 4.1.3 Temperature Sensing Technology Used in Oceanography and Measurement Errors 4.2 Salinity 4.2.1 The Historical Definitions of Salinity 4.2.2 The Conductivity of Seawater and Its Measurement 4.2.3 Technology of Conductivity Sensors 4.2.4 Calibration of Conductivity Sensors 4.2.5 Instruments under Development to Measure Absolute Salinity 4.3 Pressure 4.3.1 Why and How Do We Measure Pressure? 4.3.2 Pressure Sensors Technologies and Calibration 4.4 Current 4.4.1 Why and How Do We Measure Currents? 4.4.2 Operating Principles of Doppler Current Meters 4.4.3 Calibration Methods of Doppler Current Meters References Chapter 5: Metrology for the Sea: Chemical Quantities 5.1 Measuring in the Chemical Sciences 5.1.1 Definitions Are Not Boring, but Highly Exciting 5.1.2 From Sampling to Measurement 5.1.3 Calibration and Metrological Traceability 5.1.4 Validation of Analytical (Measurement) Procedure 5.1.5 Measurement Uncertainty 5.1.6 Reporting Measurement Result 5.1.7 Errors 5.2 Quality Criteria for the Seawater and Seafood 5.3 Measuring 210Po in the Gulf of Trieste and Acidity in Olive Oils References Chapter 6: Sensors, Measurements, and Analysis for Underwater Acoustic Investigation 6.1 Introduction 6.1.1 Why Acoustics 6.1.2 Terminology, Units, and Measurements Parameters 6.1.3 How to See the Sound 6.1.4 Fundamental Concepts of SONAR Equation 6.2 Acoustic Sensors 6.2.1 Transducer 6.2.2 Ceramics Measurement and Usage 6.2.3 SONAR Sensors 6.2.4 Single–Multi-Beam Echo Sounder 6.2.5 Side-Looking SONAR 6.2.6 Acoustic Baseline 6.3 Localization, Processing, and Analysis 6.3.1 Target Motion Analysis 6.3.2 Triangulation 6.3.3 Time Difference of Arrival or Cross-Correlation Method 6.3.4 Multipath Passive Ranging 6.3.5 Conventional Beamforming 6.3.6 Spectral Analysis 6.3.7 Image Processing 6.4 Measurements and Applications 6.4.1 Underwater Radiated Noise 6.4.2 Transducer Evaluation and Measurement 6.5 The Unmanned Way to the Acoustic Investigation 6.5.1 Manned-Unmanned C3S and the Security Issue 6.5.2 Interoperability Between Heterogeneous Assets 6.5.3 Autonomous Behavior and Navigation 6.5.4 Long-Endurance Vehicles for Long-Term Missions 6.6 Conclusion References Chapter 7: Measurement of Sea Waves 7.1 Modelling and Measuring of Sea Waves 7.1.1 Ocean Waves: A Brief Review 7.1.2 Wave Spectra 7.1.3 Sea Wave Monitoring Techniques 7.2 Spectral Analysis of Sea Waves 7.2.1 Spectrum Estimation 7.2.2 Spectral Analysis of Simulated Sea Wave Measurement Data 7.2.3 Estimation of Sea State Parameters from Estimated Spectra 7.3 Sea Wave Monitoring Based on Ship Motion Measurement and Analysis 7.3.1 A Brief Theoretical Review 7.3.2 Assessment of Sea State Parameters 7.3.3 Assessment of Sea State Parameters 7.4 Sea Wave Monitoring by Coastal HF Radars 7.5 Future Developments References Chapter 8: Remote Sensing Applications in Satellite Oceanography 8.1 Introduction 8.2 Technical Background 8.2.1 Electromagnetic Radiation 8.2.2 Satellite Orbits 8.2.3 Imaging Techniques and Data Processing 8.3 Visible Imagery 8.3.1 Ocean Color Measurements 8.3.2 Sensors and Platforms 8.3.3 Ocean Color Applications 8.4 Infrared Radiometry 8.4.1 Sea Surface Temperature Infrared Observations 8.4.2 Ice Surface Temperature 8.5 Passive Microwave Radiometry 8.5.1 Physical Aspects 8.5.2 Wind Speed and Sea Surface Temperature 8.5.3 Sea Surface Salinity 8.5.4 Sea Ice Applications 8.6 Synthetic Aperture Radar 8.6.1 Basics of Synthetic Aperture Radar Imaging 8.6.2 Small-Size Satellites Technology 8.6.3 The ICEYE Constellation Mission 8.6.4 SAR Wind Speed Retrieval 8.7 Radar Altimetry References Chapter 9: Sea Monitoring Networks 9.1 Introduction 9.1.1 Scope and Main Types of Marine Observation Network 9.1.2 Towards an Integrated Observation System 9.2 Design of a Sea Monitoring Network 9.2.1 Identification of the Best Equipment 9.2.2 Identification of the Optimal Spatial and Temporal Sampling 9.2.3 The Identification of the Best Location and the Right Number of Stations 9.3 Management of a Sea Monitoring Network 9.3.1 Logistics and Administrative Aspects 9.3.2 The Fundamental Role of the Maintenance Operations 9.3.3 Possible Expected and Unexpected Events During the Network Life 9.3.4 The Principal Costs of a Sea Monitoring Network 9.4 Data Management and Dissemination 9.4.1 Validation 9.4.2 Data Dissemination and Open Data 9.5 Some Examples of Operative Sea Monitoring Network 9.5.1 The In Situ Buoys Network 9.5.2 The In Situ Tide Gauges Network 9.5.3 The Coastal HF Radars Oceanographic Network 9.5.4 The Seismic Signal Network as a Challenging Way to Measure the Sea State 9.5.5 Ship-Based Observation 9.5.6 Animal-Borne Instruments References Chapter 10: Sea Level Measurement 10.1 Measurements of Sea Height 10.2 Relative and Absolute Height 10.3 Sea Level Uncertainty and Total Error Budget 10.4 Uses of Water Level for Marine Dynamics Environment 10.4.1 Ocean Tide and Sea Level Measurement 10.4.2 Ocean Dynamics, Climate and Water Level Data 10.4.3 Hydrography and Navigation 10.5 Sea Level Networks 10.6 Data Archaeology: Long-Term Time Series References Chapter 11: Measurements in Marine Geology: An Example in the Gulf of Taranto (Northern Ionian Sea) 11.1 Introduction 11.2 Geomorphology 11.2.1 The Taranto Landslide 11.3 Stratigraphy and Sedimentology 11.3.1 The Laser Granulometer 11.3.2 Content of Carbonate 11.3.3 Content of Biogenic and Terrigenous Clasts 11.3.4 X-Ray Fluorescence Analysis 11.3.5 Outcomes of Sedimentological and Stratigraphic Measurements on C5 Core References Chapter 12: Computer Vision and Deep Learning Applied to the Photo-identification of Cetaceans 12.1 Introduction 12.2 Contour-Based Photo-identification 12.3 Smart Photo-Identification of Risso’s Dolphins 12.3.1 Convolutional Neural Networks 12.3.2 Image Cropping 12.3.3 Recognition of an Already Cataloged Dolphin 12.4 SPIR 12.5 Conclusions References Chapter 13: Economic and Legal Implications of Setting Standards: The Case of ISO Containers 13.1 A Brief History of Shipping Containers’ Standardization 13.2 Benefits of Containers’ Standardization 13.3 ISO Standards Regarding Freight Containers: The ISO 668:2020 Series 1 13.4 Juridical Nature and Legal Issues of ISO Standards for Freight Containers 13.5 Economic Implications of Standards for Network Industries 13.5.1 Transport as a Network Industry 13.5.2 The Role of Standards in Network Industries 13.6 The Impact of Containers on the Shipping Industry 13.6.1 The Containerization of Commodities 13.7 The Effects on Transport-Related Industries 13.8 Conclusion