**About the Editors**

**Andrew Clive Banks** is a senior researcher in satellite oceanography. He has more than 20 years of research experience in Earth observation/remote sensing since his first publication in the field in 1997 and is now author of more than 70 papers in peer-reviewed journals and international conference proceedings. His academic qualifications are from premier United Kingdom institutions in the field of Earth observation: B.S. (Honours) in Physical Geography from the University of Reading in 1993 (concentrating on remote sensing in collaboration with NUTIS, the NERC Unit for Thematic Information Systems); M.S. in Remote Sensing from University College London (UCL) and Imperial College in 1994; and Ph.D. in remote sensing and environmental physics from the NERC Environmental Systems Science Centre in 2000 (formerly NUTIS, now part of the University of Reading Department of Meteorology). Dr. Banks was a satellite oceanography researcher at the Hellenic Centre for Marine Research (HCMR) for 12 years (2000–2012) before gaining wider international experience, first at the Joint Research Centre of the European Commission as a scientific officer for satellite oceanography for three years (2012–2015) and then as a senior research scientist in Earth observation and climate at the National Physical Laboratory (NPL) of the U.K. for a further three years (2015–2018). In 2018, Dr. Banks returned to HCMR as the principal research scientist for satellite oceanography and marine optics at the Institute of Oceanography. During his career, he has worked on more than 30 international projects including as a PI in FRM4SOC. His research interests include: Earth observation, satellite oceanography (biological and physical), ocean color, marine optics, radiative transfer modelling, climate change and essential climate variables, validation and vicarious calibration of satellite data, accuracy of satellite and in situ data (uncertainty and SI-traceability), fiducial reference measurements, and open ocean and coastal remote sensing of the Hellenic Seas and East Mediterranean. He has chaired a number of international remote sensing conference and workshop sessions, has been an expert projects evaluator for the European Commission under different framework programmes, is a reviewer for journals such as *Remote Sensing of Environment*, the *International Journal of Remote Sensing*, and *Frontiers in Marine Science*, and is currently an Editorial Board Member for MDPI Remote Sensing.

**Christophe Lerebourg** was awarded a Ph.D. in marine optics from the University of Plymouth (U.K.). He then worked for two years at the Federal University of Rio Grande (Brazil) on in situ radiometric measurements and EO data processing in the context of ocean color and SST studies. He joined ACRI-ST in 2006 to work on various projects requiring a strong expertise in ocean sciences, optical remote sensing, and bio-optics. His activities have included: (1) Copernicus GBOV service manager (https://land.copernicus.eu/global/gbov); (2) OLCI A & B vicarious calibration and operational Cal/Val; (3) Vicarious calibration for MERIS 3rd and 4th data reprocessing (algorithm development and operational implementation); (4) MERIS and Sentinel-3 Cal/Val activities; (5) MERMAID facility specification and development; (6) ODESA processing platform development and organization of training for the OC users community; (7) Organization and implementation of ocean color workshops as president of the GIS COOC executive committee; (8) In situ data collection and quality control to populate MERMAID matchup database; and (9) Algorithm development and data validation in the GlobColour project. As part of the MERIS maintenance activities, he has been deeply involved in the development of the MERIS vicarious adjustment procedure. With the MERIS mission, he is currently involved in the Sentinel-3 Mission Performance Centre for the specification, development, and exploitation of multi-sensor Cal/Val tools for Sentinel-3. In particular, he has extended the MERMAID facility for OLCI validation activities. His expertise in MERIS vicarious calibration is of prime interest for the development of the OLCI vicarious calibration procedures. In addition, he has been involved in various OC projects for CNES, such as the development of the Kalicotier platform, the development and the assessment of new generation OC algorithms, ˆ and in-flight calibration of OC sensors. Finally, Dr. Lerebourg is involved in the definition of the Geo-OCAPI mission and is president of the GIS-COOC Executive Committee (French scientific group on ocean color).

**Kevin Ruddick** is the Remote Sensing and Ecosystem Monitoring (REMSEM) team leader at the Operational Directorate for the Natural Environment (ODNature) of the Royal Belgian Institute for Natural Sciences (RBINS). His academic training involved obtaining a Ph.D. in Oceanography (Docteur en Sciences) from the Universite de Li ´ ege, Belgium, in 1995, after a M.S. ` in Marine Environmental Modelling (1992) from the Universite de Li ´ ege, Belgium, a M.S. in Fluid ` Dynamics (1988) from the von Karman Institute, Belgium, and a B.A. in Mathematics (1987) from the University of Cambridge, United Kingdom. Dr. Ruddick has a general interest in understanding how the physical environment (light, temperature, currents, etc.) affects life in the sea with more specific interests and expertise in marine optics and remote sensing, including: algorithms for total suspended matter, chlorophyll-a, diffuse attenuation, turbidity, (harmful) algal blooms, etc.; atmospheric correction, especially for turbid waters; in situ validation measurements, especially recorded the most accurate possible reflectance measurements and understanding their uncertainty; geostationary ocean color, the next ocean color revolution; marine reflectance spectra from the blue to the short wave infrared (400–3000 nm); coastal water applications of remote sensing data; and the underwater light climate. Dr. Ruddick has participated in many cruises and field campaigns using above water radiometry with a large number of other teams from a large diversity of platforms, both fixed and ship-based.

**Gavin Tilstone** is a U.K. Natural Environment Research Council (NERC) Merit Scientist with over 25 years' experience in the fields of optics, phytoplankton, photosynthesis, primary production, and remote sensing ocean color. He leads research on satellite ocean color validation and algorithm development and on water quality, including detecting harmful algal blooms and the use of satellite ocean color in quantifying the marine carbon cycle. He impacts policy implementation using primary production derived from space observations for OSPAR. He leads a team of optical and remote sensing scientists who develop and apply his research within international, European, and UKRI research projects. He leads the Sentinel-3 EUROHAB web alert system project, and three European Space Agency (ESA) projects on the validation, uncertainty quantification, and development of CO2 flux products using Sentinel data. He has been PI and Co-I on four ESA contracts and two European Union (EU) INTERREG contracts. He has published over 85 peer-reviewed papers, with an H-index of 30. Education 1993–1996 University of Exeter, U.K., Ph.D., Botany. Multiple Metal Tolerance in Mimulus guttatus. 1990–1992 University of Swansea, U.K., B.S. (Hons.) Environmental Biology 2:1. Professional Experience 1997–1999 PDRA, Instituto Investigaciones Marinas CSIC, Vigo, Spain. 1999–2000 PDRA, Universite Libre de Bruxelles / MUMM, Brussels, Belgium. 2000–2004 NERC Scientist (Band 6) at PML, U.K., on NERC MARPROD 1 (NER/T/S/1999/00070). 2004–2018 NERC Senior Scientist (Band 5), Plymouth Marine Laboratory, U.K. 2018–present Merit Scientist (NERC Band 4), Plymouth Marine Laboratory, U.K. Successful Funding Applications PI on: ESA AMT4OceanSatFlux (ESRIN/RFQ/3-14457/16/I-BG); EU INTERREG Va S-3EUROHAB; ESA AMT4SentinelFRM (ESRIN/RFQ/3-14457/16/I-BG); NERC-FAPESP SemSAS (NE/P00878X/1); ESA Extreme Case 2 waters (C2X) (4000113691/15/I-LG); EU Marie Curie EIF "UVphytoMAA" for Kadija Oubelkheir; NERC small grant "Backscatter for ERSEM" (NE/C514215/1); EU FP5, REVAMP (EVG1–CT–2001–00049); ESA COASTDRIVE, (ESRIN AO/1-4240/02/I-LG). Co-I on: ESA FRM4SOC (ESA/AO/1-8500/15/I-SBo); EU Horizons JMP EUNOSAT (11.0661/2017/750678/SUBIENV.C2); INTERREG IVA 2SEAS Information System on the Coastal Eutrophication (ISECA); NERC consortium grant "ECOMAR" (NE/C513018/1); NERC small grant "CASI-PP in estuaries" (NE/D007232/1); NERC MarProd Phase II (NE/C508385/1). WP Lead on: NERC UK SOLAS grant ICON (NE/C517176/2) Oct 2005–Sept 2010; NERC Oceans 2025, Theme 2, Mar Biogeochem in a high CO2 world. Supervisor of 8 PhDs: NE/L50189X/1, Shelf Seas Biogeochemistry Ph.D. Curran; NERC CASE Studentship; Johanna Gloel, PML Studentship Barnes, Robinson (0711560248004), Jackson, Arctic Marine productivity, Martinez-Vicente, Uni. Bangor; 2 Current Ph.D.s: Ford, GW4+ Ph.D., NERC Industrial Ph.D., Courticuisse.

**Riho Vendt** is a senior researcher in metrology and space technology. Dr. Vendt earned his Ph.D. in physics from the University of Tartu, Estonia, in 2013. For almost 20 years, he worked for the National Metrology Institute of Estonia (Metrosert, 1994–2013) in various positions: research scientist, head of section, and technical manager, and was responsible for the national standards for thermometry (2004–2012). Currently, he is a Senior Research Fellow at Tartu Observatory, University of Tartu with the Department of Space Technology. Dr. Vendt has a high level of expertise in quality assurance of tests and measurements. He has designed and piloted several intercomparison measurement campaigns. He was a member of the Technical Committee for Thermometry (TC-Therm) with the European Association of National Metrology Institutes (EURAMET) as the national representative for Estonia (2002–2013) and a member of the consultative committee for metrology at the Estonian National Accreditation Board (2000–2013). He has been an active assessor of quality management systems since 2004, the Head of the Testing, Calibration, and Space Technology Laboratories at Tartu Observatory since 2012, a member of the Scientific Council of Tartu Observatory since 2015, and a member of EURAMET's European Metrology Networks (EMN) expert group for Climate and Ocean Observation since 2019. He was also responsible for the quality assurance and testing campaign of the first satellite of Estonia, the ESTCube-1 (2012–2013). His research interests include metrology, calibration, and testing; SI traceability and uncertainty evaluation; characterization of measurement instruments; quality assurance; data validation; accuracy of in situ data; fiducial reference measurements; design of intercomparison measurements and analysis of comparison data; optical radiometry; thermometry, thermal effects and modelling; Earth observation; and space technology. He has been teaching courses and supervising students at the undergraduate and graduate levels since 2006 and has worked in several European Space Agency (ESA), EUMETSAT, European Metrology Research Program (EMRP), and other EU-funded projects. Dr. Vendt was the coordinator of the FRM4SOC project.
