AN INTRODUCTION TO OCEAN REMOTE SENSING - …assets.cambridge.org/97811070/19386/frontmatter/9781107019386... · AN INTRODUCTION TO OCEAN REMOTE SENSING Second edition Fully updated,

AN INTRODUCTION TO OCEAN REMOTE SENSING

Second edition

Fully updated, with significant new coverage of advances in satellite oceanography andresults from new satellite missions, the second edition of this popular textbook intro-duces students to how remote sensing works, how to understand observations from Earth-observing systems, and the importance of these observations to physical and biologicaloceanography. It provides full explanations of radiative transfer, ocean surface properties,satellite orbits, instruments and methods, visible remote sensing of biogeochemical prop-erties, infrared and microwave retrieval of sea surface temperature, sea surface salinityretrieval, passive microwave measurements, scatterometer wind retrieval, altimetry andSAR. This new edition also includes descriptions of the online archives where data can beobtained, and where readers can obtain online tools for working with the data – enablinghands-on engagement with real-world observations.

This is an ideal textbook for graduate and advanced undergraduate students takingcourses in oceanography, remote sensing and environmental science, and provides a prac-tical resource for researchers and Earth science professionals working with oceanographicsatellite data.

Online resources at www.cambridge.org/oceanremotesensing:

� Links to online archives where data can be obtained� Links for readers to obtain online tools for working with the data� Full sets of figures from the book in JPEG and PPT formats

seelye martin is Emeritus Professor in the School of Oceanography at the Universityof Washington. He has been involved with passive microwave, visible/infrared and radarice research since 1979, and has made many trips to the Arctic for research on sea iceproperties and oceanography. Professor Martin has served on a number of NASA andNOAA committees and panels involving remote sensing and high-latitude processes. From2006 to 2008, he worked at NASA Headquarters as Program Manager for the Cryosphere,where he also served as program scientist for the ICESat-1 and ICESat-2 missions. From2009 to 2012, he worked in a variety of roles for the NASA high-latitude IceBridge remotesensing aircraft program. For this work, in 2012 he was awarded the NASA ExceptionalPublic Service Medal.

www.cambridge.org© in this web service Cambridge University Press

Cambridge University Press978-1-107-01938-6 - An Introduction to Ocean Remote Sensing: Second EditionSeelye MartinFrontmatterMore information

http://www.cambridge.org/9781107019386

http://www.cambridge.org







AN INTRODUCTION TO OCEANREMOTE SENSING

second edition

SEELYE MARTINSchool of Oceanography, University of Washington






University Printing House, Cambridge CB2 8BS, United Kingdom

Published in the United States of America by Cambridge University Press, New York

Cambridge University Press is part of the University of Cambridge.

It furthers the University’s mission by disseminating knowledge in the pursuit ofeducation, learning and research at the highest international levels of excellence.

www.cambridge.orgInformation on this title: www.cambridge.org/9781107019386

First edition c© Cambridge University PressSecond edition c© Seelye Martin 2014

This publication is in copyright. Subject to statutory exceptionand to the provisions of relevant collective licensing agreements,no reproduction of any part may take place without the written

permission of Cambridge University Press.

First edition published 2004Paperback edition published 2011

Second edition published 2014

Printing in the United Kingdom by TJ International Ltd. Padstow, Cornwall

A catalogue record for this publication is available from the British Library

Library of Congress Cataloguing in Publication dataMartin, Seelye, 1940–

An introduction to ocean remote sensing / Seelye Martin. – Second edition.pages cm.

Includes bibliographical references and index.ISBN 978-1-107-01938-6 (hardback)

1. Oceanography – Remote sensing. I. Title.GC10.4.R4M375 2014

551.46028′7 – dc23 2013048911

ISBN 978 1 107 01938 6 Hardback

Additional resources for this publication at www.cambridge.org/oceanremotesensing

Cambridge University Press has no responsibility for the persistence or accuracy ofURLs for external or third-party internet websites referred to in this publication,

and does not guarantee that any content on such websites is, or will remain,accurate or appropriate.






To the memory of my motherLucy Gray Martin

April 19, 1915–June 13, 2002











Contents

Preface page xiList of chemical symbols xivList of mathematical symbols xvList of abbreviations and acronyms xxi

1 Background 11.1 Introduction 11.2 Definition of remote sensing 31.3 Satellite orbits 41.4 Geosynchronous satellites 121.5 Sun-synchronous satellites 131.6 Imaging techniques 151.7 Processing levels, archives, data records and processing 221.8 Past, present and pending satellite missions 26

2 Ocean surface phenomena 352.1 Introduction 352.2 Ocean surface winds and waves 352.3 Ocean currents, geostrophy and sea surface height 462.4 Sea ice 50

3 Electromagnetic radiation 533.1 Introduction 533.2 Descriptions of electromagnetic radiation 533.3 Ways to describe EMR 613.4 Radiation from a perfect emitter 663.5 The ideal instrument 71

4 Atmospheric properties and radiative transfer 794.1 Introduction 794.2 Description of the atmosphere 794.3 Molecular absorption and emission 864.4 Scattering 90

vii






viii Contents

4.5 Atmospheric attenuation 964.6 Application to the ideal instrument 994.7 The radiative transfer equation 1014.8 Specific solutions of the radiative transfer equation 1054.9 Diffuse transmittance and skylight 110

5 Reflection, transmission and absorption at the atmosphere/ocean interface 1135.1 Introduction 1135.2 The interface 1155.3 Transmission across an interface 1225.4 Absorption and scattering properties of seawater 1265.5 Reflection from foam 135

6 Ocean color 1366.1 Introduction 1366.2 Absorption and scattering by phytoplankton, particulates and

dissolved material 1396.3 Ocean color satellite instruments 1476.4 SeaWiFS, MODIS, VIIRS and their calibrations 1526.5 Atmospheric correction and retrieval of the water-leaving radiance 1596.6 Surface validation data sets and the vicarious calibration 1696.7 Chlorophyll reflectance and fluorescence 1716.8 The empirical, semianalytic and biogeochemical algorithms 1746.9 The Pre-Aerosol, Clouds and ocean Ecosystem (PACE) mission 192

7 Infrared observations of sea surface temperature (SST) 1947.1 Introduction 1947.2 What is SST? 1977.3 Properties of AVHRR, MODIS and VIIRS bands used in the SST

retrieval 2007.4 Atmosphere and ocean properties in the infrared 2037.5 SST algorithms 2087.6 Cloud-detection and masking algorithms 2217.7 Error and bias of the data sets 2277.8 Other GHRSST data sets and merged products 2297.9 Illustrations and examples 231

8 Introduction to microwave imagers 2368.1 Introduction 2368.2 General antenna properties 2378.3 Measurement of a surface radiance with an antenna 2428.4 Conical scanners and the surface emissivity 2448.5 Antenna pattern correction (APC) 2458.6 Passive microwave imagers 248






Contents ix

9 Passive microwave observations of the atmosphere and ocean surface 2609.1 Introduction 2609.2 Atmospheric absorption and transmissivity in the microwave 2609.3 Radiative transfer in the microwave 2669.4 Dependence of the emissivity on surface waves and foam 2739.5 Temperature and salinity 2859.6 Open ocean algorithms 2889.7 WindSat retrieval of wind speed and direction 2959.8 Sea-ice algorithms 300

10 Introduction to radars 30810.1 Introduction 30810.2 Radar equation 30910.3 Determination of σ0 within an FOV 31310.4 Range binning 31510.5 Doppler binning 31910.6 Oceanic backscatter 324

11 Scatterometers 33111.1 Introduction 33111.2 Background 33311.3 How scatterometers derive the wind velocity 33611.4 NSCAT scatterometer 34211.5 AMI and ASCAT scatterometer 34311.6 The rotating beam scatterometers 34611.7 Advantages and disadvantages of the different scatterometers 35411.8 The ISS-RapidScat 35511.9 Cross-calibrated multi-platform winds (CCMP) 356

11.10 Applications and examples 356

12 The altimeter 36212.1 Introduction 36212.2 Shape of the Earth 36312.3 Past, present and future altimetric satellites 36812.4 TOPEX/POSEIDON 36812.5 JASON-1/JASON-2 37812.6 Altimeter interaction with a specular sea surface 38012.7 Effect of surface waves on the altimeter return 38512.8 Errors and biases in the retrieval of sea surface height 38912.9 Applications and examples 393

13 Imaging radars 40113.1 Introduction 40113.2 Background 402






x Contents

13.3 Resolution of side-looking radars (SLRs) 40913.4 How the SAR achieves its resolution 40913.5 RADARSAT-2 SAR 41513.6 Other operational SARs 42213.7 Applications and examples 423

14 Other instruments: the gravity missions, ICESat-1 and -2, CryoSat-2, SMOSand Aquarius/SAC-D 43614.1 Introduction 43614.2 Gravity missions 43614.3 The ICESat-1, ICESat-2 and CryoSat-2 missions 44114.4 SMOS and Aquarius/SAC-D 449

Appendix 455References 458Index 489

The color plates will be found between pages 260 and 261






Preface

Since the publication of the first edition a decade ago, the variety and use of ocean observingsatellites has continued to grow. Combined with a similar expansion in computer resourcesand in surface receiving and distribution networks, this growth has greatly increased ourknowledge of the properties of the upper ocean and the overlying atmosphere.

Ten years ago, many satellites were large, managed by single countries and carriedmultiple sensors. Now, by international agreement, different countries collaborate on con-stellations of smaller satellites that fly in complementary orbits and focus on a singleoceanic or atmospheric feature such as biology, winds or sea surface temperature (SST).Many of these data sets such as SST from the constellations are available in a commonformat from public archives that also provide software tools for working with the data.These constellations and their archives greatly improve research opportunities for studentsand professionals.

For remote sensing, the use of the electromagnetic spectrum combined with our under-standing of the oceanic surface and atmospheric properties has stimulated innovationsin instrumentation. Satellite remote sensing also uses gravity measurements that haveimproved our knowledge of the Earth’s geoid, measured the ice loss from the major icecaps, and monitored changes in the ocean circulation. Many of the experimental sensorsof the 1980s are now the operational tools of oceanography. These include narrow-bandoptical sensors to estimate biological productivity, infrared sensors to measure sea sur-face temperature that approach an accuracy necessary to observe climate change, passivemicrowave sensors that provide global cloud-independent observations of winds and seasurface temperature and salinity, and altimeters capable of measuring sea surface height towithin 2 cm.

Because remote sensing involves many disciplines, the book provides under one coverthe necessary background in electromagnetic theory, atmospheric and seawater properties,physical and biological oceanography, physical properties of the sea surface and the prop-erties of satellite orbits. The contents range from the reflective and emissive properties ofclouds and foam to the radar-scattering properties of ocean waves, to the optical propertiesof plankton-associated pigments. It also includes many examples. The book describesthe development of satellite oceanography from 1975 to 2013, and outlines pending

xi






xii Preface

missions. The book requires only an introductory knowledge of electromagnetic theoryand differential equations.

The text divides into five parts. Chapters 1–3 introduce satellite systems, ocean surfaceproperties and electromagnetic theory. Chapters 4–7 discuss remote sensing in the visibleand infrared spectrum, including atmospheric properties, the ocean/atmosphere interface,the visible retrieval of ocean color and the infrared retrieval of sea surface temperature.Chapters 8 and 9 discuss the passive microwave, including antennas, instruments, atmo-spheric properties and the retrieval of ocean surface and atmospheric variables. Chapters10–13 discuss the active microwave, including a variety of radars to retrieve wind speed anddirection, sea surface height and images of the ocean surface. Finally, Chapter 14 describesa variety of gravity and sea surface salinity missions, and sea ice and ice sheet laser andradar altimeter satellites.

I began this book during 1993–94, when I was a visiting scientist at the NationalInstitute of Polar Research in Tokyo. I wrote this edition following my retirement from theUniversity of Washington in 2011. The book benefited from my work with the NationalAeronautics and Space Administration (NASA); from my service on committees in the1980s and 1990s, from 2006–2008 when I worked at NASA Headquarters as programmanager for the cryosphere, and from 2009–2012, when I performed a variety of servicesfor the Airborne Operation IceBridge (OIB) program. I am grateful to NASA for theseopportunities. I particularly thank Dixon Butler, who was head of the Earth ObservingSystem (EOS) program, and Waleed Abdalati and Jack Kaye for their support during mytime at headquarters.

At the University of Washington, I taught remote sensing both singly and jointly withMiles Logsdon. I thank Miles and all of our students, who always managed to focus onthose points that I did not understand. In my teaching and writing, I benefited from the classnotes of Dudley Chelton, James Mueller and Carlyle Wash, and the textbooks of CharlesElachi, George Maul, Ian Robinson and Robert Stewart.

At NASA Goddard Space Flight Center (GSFC), I thank Ziauddin Ahmad, Gene Eplee,Don Cavalieri, Josephino Comiso, Charles McClain, Claire Parkinson, Jeremy Werdelland Meng-Hua Wang; at the Jet Propulsion Laboratory (JPL), Ron Kwok, Lee-Lueng Fu,Ben Holt and Simon Yueh. At MacDonald, Dettwiler and Associates (MDA), I thankJeff Hurley and Wendy Keyser. At the National Oceanic and Atmospheric Administration(NOAA), I thank Alexander Ignatov, Boris Petrenko and Mayra Pazo; at Oregon StateUniversity, Dudley Chelton; at Earth and Space Research, Gary Lagerloef and Hsun-YingKao; at Remote Sensing Systems, Chelle Gentemann, Tom Meissner and Frank Wentz; atNASA Headquarters, Paula Bontempi. I also thank Peter Wadhams from the University ofCambridge and Peter Minnett from the University of Miami for their encouragement andsupport. At Cambridge University Press, I thank Kirsten Bot, Laura Clark, Susan Francisand David Mackenzie for their help and support. For his careful line-by-line reading of themanuscript, I thank my freelance editor, Steven Holt.

At the University of Washington, I thank Jamie Morison, Cecilia Peralta-Ferriz as wellas the staff of the UW Libraries for their support and for their extensive online collection






Preface xiii

of journals. For their critical readings of draft chapters I thank Peter Cornillon for Chap-ter 1 and Boris Petrenko for Chapter 7. I also thank Alexander Ignatov for his help withunderstanding the NOAA SST processing. Any errors are my own.

I thank my son and daughter, Carl William Coryell-Martin and Maria Elizabeth Coryell-Martin, for putting up with all this even after they have left home and my wife, Julie EstherCoryell, for her optimism that I might finish the book, for reading all of the chapters indraft and for her support. Finally, I ask the reader to remember that each of the satellites,instruments and algorithms described in this book began as an idea generated by a singleindividual or a small committee.






Chemical symbols

Ar ArgonCH4 MethaneCO Carbon monoxideCO2 Carbon dioxideFe IronH2O WaterN2 NitrogenN2O Nitrous oxideO2 OxygenO3 OzoneHα, Hβ, Hγ Hydrogen lines in the Fraunhofer spectrumMg–I Magnesium–iodine lineO2-A Oxygen-A line

xiv






Mathematical symbols

Symbol Unit DefinitionA m2 Area, or instrument aperture areaAe m2 Effective antenna aperture areaAFOV area Antenna half-power field-of-viewAi(400) m−1 Reference absorption at 400 nm; i refers to particulates or

CDOMa(λ) m−1 Volume absorption coefficienta(λ; θ , φ) – Ratio of graybody to blackbody absorption; in VIR, the

absorptance, in microwave, the absorptivityaCDOM m−1 CDOM absorption coefficientaw m Amplitude of ocean surface wavesaw(λ), ap, aφ , aT m−1 Absorption coefficients for seawater, particulate,

phytoplankton and total absorptionB W m−2 sr−1 Brightness, used for radiance in the passive microwaveB tesla m−1 Magnetic field vectorBf J m−2 sr−1 Frequency form of spectral brightnessb(λ) m−1 Volume scattering coefficient of seawaterbb(λ), bbw(λ) m−1 Backscatter coefficient of pure seawaterbbT(λ) m−1 Total backscatter coefficient of seawater°C Degrees CelsiusCa mg Chl-a m−3 Chlorophyll concentrationCw, C1 – Concentrations of open water and sea icec m s−1 Speed of light in vacuumc(λ) m−1 Volume attenuation coefficient of seawaterD cm, m Aperture diameter of a lens or length of an antennad (λ) – Normalized absorption depthda(λ) m Absorption depth of radiation in seawaterE W m−2 Irradiance, the incident flux density per unit areaE V m−1 Electric field vectorE J Energy of a photonE0 V m−1 Reference amplitude of an electric field vectorEd(λ, 0+) W m−2 Downwelled solar irradiance measured just above the ocean

surface

xv






xvi Mathematical symbols

ER(χ , ψ) km Height of reference ellipsoid above Earth’s center of massEu(0−) W m−2 Upwelled solar irradiance just below the water surfaceEV, EH V m−1 Vertically and horizontally polarized components of the

electric field vectore(λ; θ , φ) – Emissivity, which is the ratio of graybody to blackbody

radiancee0 – Temperature- and salinity-dependent emissivity of a specular

ocean surfaceF(λ, z) W m−2 nm−1 Solar irradiance at a height z in the atmosphereFn – Normalized power or radiation patternFS(λ) W m−2 nm−1 Solar irradiance at the top of the atmosphereF ′

S(λ) W m−2 nm−1 FS(λ) attenuated by two passes through the ozone layerf s−1 Coriolis parameterf Hz Frequencyf(x) V m−1 Antenna illumination patternf L m Focal lengthf N s−1 Nyquist sampling frequencyfp(T, λ) W m−3 sr−1 Planck blackbody radianceG – Antenna gainG0 – Maximum antenna gainGR – Gradient ratio used in the derivation of sea-ice concentrationg m s−2 Acceleration of gravityH km Radial distance of a satellite from Earth’s center of massH1/3 m Significant wave heightHz s−1 Cycles per secondh length Height of satellite above ocean surfacehS length Height of sea surface above Earth’s ellipsoidhs length Temporal mean of sea surface heighth J s Planck constant, 6.626 × 10−34 J sI deg Inclination, the angle between the Earth’s rotation axis and

the normal to the orbit planeI(r, θ , φ) W sr−1 Radiant intensityI0 W sr−1 Maximum radiant intensityi Imaginary part of complex numberJ JoulesK Degrees Kelvink, kim m−1 Real and imaginary part of the wavenumberk m−1 Vector wavenumberkB J K−1 Boltzmann constant, 1.38 × 10−23 J K−1

kw m−1 Wave number of ocean wavesL mm Columnar equivalent of nonraining cloud liquid waterL(λ) µW cm−2 nm−1 sr−1 Radiance

W m−3 sr−1 (Alternative units of L)LA(λ) µW cm−2 nm−1 sr−1 Path radiance generated by aerosol atmospheric scatteringLE km Equatorial separation between successive orbits






Mathematical symbols xvii

Lf(λ) J m−2 sr−1 Frequency form of spectral radianceLR(λ) µW cm−2 nm−1 sr−1 Path radiance generated by Rayleigh scatteringLs(λ) µW cm−2 nm−1 sr−1 Solar radiance at the top of the atmosphereLT(λ) µW cm−2 nm−1 sr−1 Total radiance received at the satelliteLw(λ) µW cm−2 nm−1 sr−1 Water-leaving radiance[Lw(λ)]N µW cm−2 nm−1 sr−1 Normalized water-leaving radianceLλ(λ) µW cm−2 nm−1 sr−1 Wavelength form of spectral radiancel m Length of an imaging radarM W m−2 Exitance, or emitted flux or power densityN(χ , ψ) m Geoid undulation, or height of geoid relative to the

reference ellipsoid ERNp, nepers – Units of atmospheric absorption used in microwaveNE�T K Noise-equivalent delta-temperatureNE�L µW cm−2 nm−1 sr−1 Noise-equivalent delta-radianceNE�σ 0 – Noise-equivalent delta-sigma-zeron – Real part of the index of refractionP – For radiometers, subscript indicates V or H polarization.

For radars, subscript indicates VV or HH polarizationP(θ ) sr−1 Atmospheric scattering phase functionPR – Polarization ratio used in the derivation of sea-ice

concentrationPR(θ ) sr−1 Rayleigh atmospheric scattering phase functionp kg m−1 s−2 Atmospheric pressureQ – Coefficient used in description of the water-leaving

radianceR(λ) – Plane irradiance reflectanceR(λ, 0−) – Irradiance reflectance evaluated just below the surfaceR0 km Distance from radar to targetRc mm, µm Radius of curvature of the sea surfaceRF(λ) – Irradiance reflectance of foamRR mm h−1 Rain rateRrs(λ) – Remote sensing reflectancer length Radiusr length Vector radius (r, θ , φ)r(θ ) – Unpolarized radiance reflectanceS psu SalinitySN – Signal-to-noise ratioSS psu Surface salinityT °C, K TemperatureT °C, K Mean temperature of the lower troposphereT(θ ) – Interface transmittanceT3, T4, T5 K AVHRR brightness temperatures for bands 3, 4, 5T22, T23, T31, T32 K MODIS brightness temperatures for bands 22, 23, 31,

32TA K Antenna temperature






xviii Mathematical symbols

Ta K Air temperatureTb K Brightness temperatureTb °C Buoy or bulk temperatureTBV, TBH K Vertically and horizontally polarized components of

brightness temperaturesText K Extraterrestrial brightness temperature exclusive of the

SunTgal K Brightness temperature of the Milky Way galaxyTS °C, K Ocean surface skin temperatureTsfc °C, K Externally supplied surface temperature to algorithmsTsol K Solar contribution to the antenna brightness temperatureTsun K Solar brightness temperatureTuniv K The 2.7-K universe background temperatureTw s Period of ocean surface wavest Timet – In the visible/infrared, the atmospheric transmittance; in

the microwave, the atmospheric transmissivitytD(λ) – Diffuse transmittanceU m s−1 The scalar wind speed at a 10-m heightU0 m s−1 Spacecraft velocityULOS m s−1 Line-of-sight wind speed, the wind speed in the

azimuthal look direction of a passive microwaveradiometer

u, v m s−1 x- and y-components of an ocean currentV mm Equivalent height in liquid water of the columnar water

vaporv m s−1 Local phase speed of lightw m Width of an imaging radarx length Vector position (x, y, z)X, Y – Coefficients used in discussion of particulate scattering

propertiesXS length Imaging radar cross-track swath widthYS length Imaging radar along-track swath widthZH km Reference height for the top of the atmosphereα deg Scattering angle relative to the forward directionα – Angstrom exponent used to describe aerosolsαS sr Solid angle resolution of an ideal optical instrumentβ(α, λ) km−1 sr−1, m−1 sr−1 Atmospheric and oceanic volume scattering functionβ(α, λ) sr−1 Oceanic scattering phase functionβ0 km−1 sr−1, m−1 sr−1 Isotropic scattering phase functionβT, βw, βp, βφ m−1 sr−1 Total, pure seawater, particulate and phytoplankton

volume scattering function�E J Energy difference associated with a change in the

internal state of a molecule or atom�f Hz, MHz Instrument bandwidth, also used to describe Doppler

shift






Mathematical symbols xix

�hion m Range delay caused by atmospheric free electrons�T45 K Temperature difference between AVHRR channels 4 and 5,

�T45 = T4 – T5

�T53 K Temperature difference between AVHRR channels 5 and 3,�T53 = T5 – T3

�x, �y m Radar resolution in the cross-track and along-track directionsφθ 1/2 deg Half-power beamwidth; for imaging radars, the half-power

beamwidth in the cross-track direction�ø1/2 deg Half-power beamwidth in the along-track directionε farad m−1 Electrical permittivityε(λ, λ0) – Single-scattering color ratio for aerosolsε0 farad m−1 Permittivity in vacuumεr – Complex dielectric constant, εr = ε′+ iε′′

ζ m Sea surface height relative to the geoidζ D m Dynamic height, or the oceanographic height calculated from

the vertical density structureη – Complex index of refraction, η = n + iχη m Vertical displacement of ocean surface wavesηM – Main beam efficiency of a microwave antennaθ deg Incidence, look or zenith angleθ S deg Solar zenith angleθv deg View or scan angleκA, κE, κS km−1 Atmospheric absorption, extinction and scattering coefficientsκR km−1 Rayleigh scattering attenuation coefficientκoxy km−1 Oxygen absorption coefficientκvap km−1 Water vapor absorption coefficientλ nm, µm Radiation wavelengthλw mm, m Wavelength of ocean surface wavesµ henry m−1 Magnetic permeabilityµ0 henry m−1 Vacuum permeability� W m−4 sr−1 Atmospheric radiative source termρ kg m−3 Density of seawaterρa kg m−3 Density of airρH, ρV – Horizontal, vertical reflection coefficientsρ ion TECU Free-electron columnar densityρw(λ) – Extraterrestrial reflectance generated by the water-leaving

radiance[ρw(λ)]N – Normalized extraterrestrial reflectanceσ siemens m−1 Electrical conductivityσ m2 Radar scattering cross sectionσ 2 – Mean-square sea surface slopeσ 0 – Normalized radar scattering cross section (pronounced

sigma-zero)σ N – Standard deviation of noise






xx Mathematical symbols

σ VV, σ HH, σ HV, σ VH – Normalized radar scattering cross section for VV, HH, HVand VH transmitting and receiving

ση m Root-mean-square sea surface heightτ s Pulse duration or lengthτ (λ) – Optical depthτA – Optical depth associated with aerosol scatteringτOZ – Optical thickness of the ozone layerτR(λ) km Rayleigh optical thickness, atmosphere� W Radiant flux or power�N W Noise generated internally to an instrument�T W Total radiant flux or power transmitted by an antenna�(V, H) W V-pol or H-pol radiant flux received by an antenna�λ W µm−1 Spectral form of the radiant flux�σ W Received power corrected for atmospheric attenuationφ deg Azimuth angleφR deg Azimuthal angle relative to the wind directionφW deg Azimuthal wind directionχ – Imaginary part of the index of refractionχ , ψ deg Latitude, longitude� sr Solid angle�E s−1 Angular rotation of the Earth�M sr Main beam solid angle of a microwave antenna�P sr Pattern solid angle of a microwave antennaω s−1 Radian frequency of an electromagnetic waveω0(λ) – Single-scattering atmospheric albedoωA(λ) – Aerosol single-scattering albedoωR(λ) – Rayleigh single-scattering albedo






Abbreviations and acronyms

A-Train The A- or afternoon train is a constellation of satellites in thesame orbit with a 1:30 pm equator crossing time

AATSR Advanced ATSR (ESA)ABI Advanced Baseline Imager (instrument on GOES-R)ACSPO Advanced Clear-Sky Processor for Ocean (NOAA)ADEOS-1, -2 Advanced Earth Observing Satellite (Japan)AGC Automatic Gain Control (altimeter function)AHRPT Advanced High Resolution Picture Transmission (METOP)ALOS Advanced Land Observing Satellite (Japan)ALT Altimeter on TOPEX/POSEIDONAMSR Advanced Microwave Scanning Radiometer (Japan) on

ADEOS-2AMSR-E AMSR-EOS (Japan) on AQUAAOML Atlantic Oceanographic and Meteorological Laboratory (NOAA)AOP Apparent Optical PropertiesAPC Antenna Pattern CorrectionAPT Automatic Picture Transmission (data transfer mode for AVHRR)AQUA Second major EOS satellite (not an abbreviation)ASAR Advanced SAR (ENVISAT)ASCAT Advanced Scatterometer (METOP)ATSR Along-Track Scanning Radiometer (ESA)AVHRR Advanced Very High Resolution Radiometer (United States)AVISO Archiving, Validation and Interpretation of Satellite

Oceanographic data (France)Caltech California Institute of TechnologyC-band Frequencies of about 5 GHzCCMP Cross-Calibrated Multi-Platform (wind dataset)CDOM Colored Dissolved Organic MaterialCHAMP CHAllenging Minisatellite Payload (German gravity mission)Chl-a Chlorophyll-a

xxi






xxii Abbreviations and acronyms

CDR Climate Data RecordCEOS Committee on Earth Observation SatellitesCONAE Comision Nacional de Actividades Espaciales (Argentinian

Space Agency)CNES Centre National d’Etudes Spatiales (National Center for Space

Studies, France)CryoSat-2 ESA radar satellite for sea ice and ice sheet studiesCRTM Community Radiative Transfer ModelCSA Canadian Space AgencyCZCS Coastal Zone Color ScannerdB DecibelsDMSP Defense Meteorological Satellite Program (United States), also

name of a satelliteDOD Department of Defense (United States)DORIS Doppler Orbitography and Radiopositioning Integrated by

Satellite (France)ECMWF European Centre for Medium-range Weather ForecastsEDR Environmental Data RecordEFOV Effective Field-Of-View; shape of the FOV after time-averagingEM ElectromagneticEMR Electromagnetic RadiationENVISAT Environmental Satellite (ESA)EOS Earth Observing System (United States, with international

components)ERS-1, -2 European Remote-sensing SatelliteESA European Space AgencyESMR Electrically Scanned Microwave Radiometer (United States)EUMETSAT European Organization for the Exploitation of Meteorological

SatellitesFLH Fluorescence Line HeightFM Frequency ModulationFOV Field-Of-View, see also EFOV, IFOVFRAC Full Resolution Area Coverage (AVHRR, MODIS, VIIRS)FY Feng Yun (Wind and Cloud) as in FY-1C and FY-1D; name of

satellite (China)FY First Year, as in first-year sea iceGAC Global Area Coverage (AVHRR data mode)Gbit Gigabit or 109 bitsGCOM Global Change Observation Missions (Japan)GDAS Global Data Assimilation System (NCEP)GEO Group on Earth Observations






Abbreviations and acronyms xxiii

GES DISC Goddard Earth Sciences, Data and Information Services Center(NASA)

GEOSS Global Earth Observation System of SystemsGLAS Geoscience Laser Altimeter System (United States)GLI Global Imager, ocean color instrument on ADEOS-2 (Japan)GMES Global Monitoring for Environment and Security (European

satellite program)GOCE Gravity Field and Steady-State Ocean Circulation Explorer (ESA)GODAE Global Ocean Data Assimilation ExperimentGOES Geostationary Operational Environmental Satellite (United

States)GHz GigahertzGHRSST GODAE High Resolution STTGIOVANNI Geospatial Interactive Online Visualization ANd aNalysis

Infrastructure; often written as GiovanniGMPE GHRSST Multi-product Ensemble (UK Met Office)GRACE Gravity Recovery and Climate ExperimentGSM Garver–Siegel–Maritorena algorithm (ocean biology)HH Antenna that transmits and receives with an H-polarizationH-pol Horizontally polarizedHRD Hurricane Research Division (NOAA)HRPT High Resolution Picture Transmission (AVHRR data transfer

mode)HV Antenna that transmits with an H-polarization and receives with a

V-polarizationHY Haiyang (Ocean) satellite as in HY-1 (China)IAPSO International Association for Physical Sciences of the OceanICESat Ice, Cloud and land Elevation Satellite (United States)IEEE Institute of Electrical and Electronics EngineersIFOV Instantaneous Field-Of-View, or Instrument Field-Of-ViewIJPS Initial Joint Polar-orbiting operational satellite System (United

States, EUMETSAT)IOP Inherent Optical PropertiesIPO Integrated Project Office (NPOESS)IR InfraredITCZ Inter-Tropical Convergence ZoneJASON-1, -2, -3 United States/France altimeter satellites (not an abbreviation)JAXA Japan Aerospace Exploration Agency (replaced NASDA)JERS-1 Japanese Earth Resources SatelliteJMA Japan Meteorological AgencyJMR Jason Microwave RadiometerJPL Jet Propulsion Laboratory (NASA), operated by Caltech






xxiv Abbreviations and acronyms

JPSS Joint Polar Satellite SystemK-band Frequencies between 11 and 36 GHzKu-band Frequencies of about 14 GHzKOSMOS USSR satellite seriesLAC Local Area Coverage (data mode for AVHRR)L-band Frequencies of about 1 GHzLRA Laser Retroreflector ArrayM-AERI Marine-Atmosphere Emitted Radiance Interferometer (United

States)Mbps Megabits-per-secondMCSST Multi-Channel Sea Surface Temperature (algorithm)MEDS Maritime Environmental Data Service (Canada)MERIS Medium Resolution Imaging Spectrometer (ENVISAT)METEOSAT Geosynchronous Meteorology Satellite (EUMETSAT)METOP-A, -B, -C METeorologie OPerationnelle (Operational Meteorology)

(EUMETSAT satellite)MHz MegahertzMOBY Marine Optical BuoY (ocean color calibration buoy near Hawaii)MODI Moderate Resolution Visible/Infrared Imager (China)MODIS Moderate Resolution Imaging Spectroradiometer on TERRA,

AQUAMODTRAN Program for calculation of atmospheric transmissivityMOS Modular Optical Scanner (Germany)MSL Mean Sea LevelMVIRSR Multispectral Visible–Infrared Scanning Radiometer (China)MY Multiyear, as in multiyear sea iceNASA National Aeronautics and Space Administration (United States)NASDA National Space Development Agency (Japan), see JAXANCEP National Centers for Environmental Prediction (NOAA)NDBC National Data Buoy Center (United States)NDT Nitrate-Depletion TemperatureNESDIS National Environmental Satellite Data and Information Service

(United States)NIR Near infraredNLSST Nonlinear SST (algorithm)NOAA National Oceanic and Atmospheric Administration (United

States)NOAA-18, -19, . . . Names of NOAA operational polar orbiting satellitesNOMAD NASA bio-Optical Marine Algorithm DatasetNPOESS National Polar-orbiting Operational Environmental Satellite

System (United States)NPP NPOESS Preparatory Project (United States)






Abbreviations and acronyms xxv

NRCS Normalized Radar Cross SectionNSCAT NASA Scatterometer (ADEOS-1)NWP Numerical Weather PredictionOC3M Ocean Chlorophyll Version 3 MODIS bio-optical algorithmOC4 Ocean Chlorophyll Version 4 SeaWiFS bio-optical algorithmOBPG Ocean Biology Processing Group (NASA)OCTS Ocean Color and Temperature Sensor (Japan)OISST Optimally Interpolated SSTOKEAN Series of satellites (Russia/Ukraine)OLS Optical Line Scanner (visible/infrared instrument on DMSP)OVWM Ocean Vector Wind MissionOW Open Water (sea-ice algorithms)PALSAR Phased Array L-band SAR (Japan)Pixel Abbreviation for picture elementPMEL Pacific Marine Environmental Laboratory (NOAA)POD Precision Orbit DeterminationPO.DAAC Physical Oceanography Distributed Active Archive (NASA JPL)POES Polar Operational Environmental Satellite (United States)POLDER Polarization and Directionality of the Earth’s Reflectances

(France), ocean color instrument on ENVISATPOSEIDON Premier Observatoire Spatial Etude Intensive Dynamique Ocean

et Nivosphere, French contribution to TOPEX/POSEIDONsatellite

PRF Pulse Repetition Frequencypsu Precision salinity units (units of oceanic salinity)RA-2 Radar Altimeter-2 (ENVISAT altimeter)RADARSAT-1, -2 SAR satellites (Canada)RGB Red–Green–Blue color mixingRGPS RADARSAT Geophysical Processing System (United States)rms Root-mean-squarerss Root-sum-of-the-squaresRTE Radiative Transfer EquationSAC-D Satelite de Aplicaciones Cientıficas-D (CONAE)SAR Synthetic Aperture RadarSASS SEASAT-A Satellite Scatterometer (United States)ScanSAR Wide-swath SAR imaging mode (partial abbreviation)SDR Sensor Data RecordSeaBAM SeaWiFS Bio-optical Algorithm Mini-WorkshopSEASAT First ocean observing satellite (1979, United States)SeaWiFS Sea-viewing Wide Field-of-view Sensor (United States)SeaWinds Radar vector wind instrument (not an abbreviation)SEVIRI Spinning Enhanced Visible and Infrared Imager (EUMETSAT)






xxvi Abbreviations and acronyms

SGLI Second-generation GLobal Imager (Japan)SIRAL SAR Interferometric Radar Altimeter (ESA)SLAR Side-Looking Airborne RadarSLR Side-Looking RadarSLR Satellite Laser RangingSMMR Scanning Multichannel Microwave Radiometer (United States)SMOS Soil Moisture and Ocean Salinity instrument (ESA)SSALT Solid State Altimeter on TOPEX (France)SSH Sea Surface HeightSSM/I Special Sensor Microwave/Imager (United States)SSMI/S Special Sensor Microwave Imager/Sounder (SSM/I upgrade)SSS Sea Surface SalinitySST Sea Surface TemperatureSWH Significant Wave Height (H1/3)TECU Total Electron Content Unit (1 TECU = 1016 electrons m−2),

columnar concentration of free electronsTERRA First major EOS satellite (not an abbreviation)TIR Thermal-InfraredTIROS-N Television Infrared Observation Satellite-N (early version of

POES satellite)TIW Tropical Instability WavesTMI TRMM Microwave Imager (Japan)TMR TOPEX Microwave RadiometerTOA Top Of the AtmosphereTOGA-TAO Tropical Ocean Global Atmosphere–Tropical Atmosphere OceanTOMS Total Ozone Mapping SpectrometerTOPEX TOPography EXperiment (United States/France altimeter)TRMM Tropical Rainfall Measuring Mission (United States/Japan)TRSR Turbo Rogue Space Receiver BlackJack GPS receivers (Satellite

GPS receivers used on JASON-1)UK Met Office United Kingdom Meteorological OfficeUTC Universal Time CoordinatedUV UltravioletVAM Variational Analysis MethodVH Antenna that transmits with a V-polarization and receives with an

H-polarizationVIRR Visible and Infrared Radiometer (China)VIIRS Visible/Infrared Imager/Radiometer Suite (NPP instrument)VIR Visible/InfraredVNIR Visible/Near-InfraredV-pol Vertically polarizedVV Antenna that transmits and receives with a V-polarization






Abbreviations and acronyms xxvii

WindSat Polarimetric radiometer for vector wind measurements (not anabbreviation)

WVSST Water Vapor Sea Surface Temperature (algorithm)X-band Frequencies of about 10 GHz






Documents

AN INTRODUCTION TO OCEAN REMOTE SENSING - …assets.cambridge.org/97811070/19386/frontmatter/9781107019386... · AN INTRODUCTION TO OCEAN REMOTE SENSING Second edition Fully updated,