Second IOCCG Committee Meeting
Tokyo, Japan, 17-18 March, 1997
The meeting took place at the Headquarters of the National Space Development Agency of Japan (NASDA) in Tokyo. All committee members were present except for Dr. Kopelevich, whose visa did not arrive in time. In addition, several observers also attended (see copy of the participants list).
1. Opening of the meeting and adoption of the agenda
The meeting was opened by Dr.Tasuku Tanaka, Director the Earth Observation Research Center (EORC-NASDA). He welcomed the participants and mentioned that the ocean- colour community would benefit from the new global data set of pigment distributions, recently released by NASDA. The chairman, Dr. Trevor Platt, thanked Dr. Tanaka for hosting the second session of the IOCCG at the NASDA Headquarters and thanked all participants for attending. The adoption of the agenda was proposed by the chairman and was accepted by consensus (see copy of agenda).
2. Matters arising from the previous meeting of the IOCCG
The Chairman gave a brief chronology of the IOCCG since the first meeting in Toulouse, France (22-23 March, 1996). In April of 1996, Dr. Platt met with the Executive Secretary (Dr. Kullenberg) and the Chairman (Mr. Holland) of the IOC to discuss the resolutions of the Toulouse meeting and the intent of the space agencies to commit funds to the IOCCG. On the basis of this discussion, the IOC agreed to commit infrastructure support to the IOCCG at a level commensurate with the level of sponsorship by individual space agencies. Dr. Platt then solicited funding for the IOCCG from the relevant space agencies.
Subsequently, the Executive Committee of the IOCCG (which consists of senior representatives of the principal donor agencies plus the Chairman), met in Washington at the NASDA offices on 5 - 6 December, 1996. At this meeting it was decided that a Project Office should be set up at the Bedford Institute of Oceanography, Canada, and that a project scientist should be appointed, initially on a half-time basis, effective from 1 January 1997. It was also decided that the IOCCG should contribute to existing newsletters to disseminate information about the IOCCG, using the not-for-profit magazine, backscatter, published by the Alliance for Marine Remote Sensing (AMRS) as its primary outlet. The first issue with an IOCCG contribution was published in February 1997. In addition, the IOCCG submitted a contribution for the February 1997 issue of the CEOS newsletter. It was also decided that there should be a server for the IOCCG on the World-Wide Web. Dr. Schlittenhardt of the JRC (Joint Research Center) agreed to make available to the IOCCG use the server in Ispra, Italy for this purpose.
The interim set of Terms of Reference, initially drafted at the workshop in Sidney, Canada, 1995 and amended at the first meeting of the IOCCG in Toulouse, France, 1996 was accepted by consensus.
3. Establishment of a Project Office for the IOCCG
A project office has been set up at the Bedford Institute of Oceanography in Dartmouth, Nova Scotia, Canada and Dr. Venetia Stuart has been appointed as Project Scientist, on a half-time basis, as start-up staffing.
4. Establishment of a Publication Outlet for the IOCCG
The IOCCG is currently using the backscatter magazine, published four times a year, as a publication outlet and has contributed 10 pages to the February 1997 issue of the magazine. Contributions to future issues will probably be 4 - 6 pages long and the Project Scientist will be requesting help from members in supplying articles. The magazine has a targeted circulation of around 7,000 in the marine remote sensing community with a projected circulation of 10,000 including IOC delegates, IOCCG committee members and CEOS Principals and Contacts. Other newsletters, such as the CEOS Newsletter, may be used from time to time. Dr. Mueller suggested that the IOCCG might consider another publication such as EOS to reach a broader distribution.
5. Establishment of the IOCCG on the World-Wide-Web
Following the invitation by Dr. Schlittenhardt that the IOCCG make use of the server in Ispra, Italy, Dr. Stuart travelled to Italy for a week in mid-February to make the necessary arrangements to establish the IOCCG Home-Page. Funding for this trip was kindly provided by Dr. Schlittenhardt through the JRC. Working in collaboration with D.J.L. Software Consultancy Limited (on contract to the JRC) a provisional Home-Page for the IOCCG was set up. After a brief presentation of the structure and demonstration of the Home-Page to the meeting, it was decided that the address of the server would be formally announced in the near future after implementation of some changes. Suggestions for change included implementing links to data archives, national working groups, ground truth programs and OCTS data.
6. Status of Ocean Colour Missions
Brief overviews were given on ocean-colour missions in various agencies in order to update the IOCCG on the status of these missions and to elucidate the role of the IOCCG in helping these missions to achieve their goals.
Dr. Neumann stressed that inter-mission calibrations should be encouraged. He also suggested that the IOCCG help in NASA/MOS negotiations, which Dr. Yoder of NASA agreed to follow up. The second MOS sensor (on the Priroda satellite) has a smaller swath, lower resolution and less coverage than the one on the IRS-P3. No data have been received from this sensor yet, but should be available within the next few weeks.
Following the presentation, some discussion ensued over the availability of MOS data, especially in the USA where there are problems with the specific frequency of the downlink. Dr. Platt resolved to write to NASA to motivate for downlink capabilities of MOS data over USA.
(d) SeaWiFS and MODIS
Following these presentations, some discussion ensued about the trends in design of ocean-colour sensors: more capability is being gained by additional spectral bands in the new advanced optical sensors, but capability is also being lost in the areas of tilt, coverage and downlink capabilities. Other problems frequently encountered are equatorial crossing times (which are often optimized for land use), gain changes for land observation and the tremendous expense in calibrating these advanced sensors. Since it is very difficult to develop a sensor for both land and ocean use, some compromises have to be made.
7. Calibration of Ocean-Colour Sensors to Common Standards
Dr. Neumann presented a brief summary of the problems regarding the absolute radiometric calibration of ocean-colour sensors to universal common standards. Different ocean-colour sensors use different radiometric sources, diffuser materials and measurement setups. The IOCCG could contribute by initiating standard protocols for setup, sources and algorithms as well as supporting intercalibration sites, promoting annual multi-mission calibration experiments and encouraging intercomparisons of national standards.
8 (a) Validation of Ocean-Colour Sensors to Common Standards
Dr. Morel gave an informal review of the four categories of activities related to validation of ocean-colour sensors: i) absolute and relative radiometric calibration of sensors, as discussed above; ii) validation of the signal measured at the top of the atmosphere: comparison between received and reconstructed signals using coincident measurements made by ship or satellite; iii) calibration/validation of algorithms used for atmospheric correction: comparison of measured in situ water-leaving radiance or reflectance with retrieved measurements, and also comparison of actual aerosols with retrieved aerosols; and iv) validation of final marine products either directly, through comparison of measured and retrieved concentrations (which requires coincident measurements), or indirectly, by comparing actual concentrations with that retrieved from apparent optical properties (coincident measurements not required).
8 (b) Validation of Atmospheric Correction for Ocean-Colour
Dr. Deschamps presented information on the SIMBAD (Satellite Validation for Marine Biology and Aerosol Determination) instrument, designed to measure aerosol and marine reflectances underway using commercial ships and research vessels of opportunity. The development of the SIMBAD instrument was initiated for POLDER ocean-colour validation, but is available to support other sensors such as OCTS and SeaWiFS. In general, a good agreement was found between chlorophyll and reflectance ratios for SIMBAD and the model of Morel (1988). To date there are ten SIMBAD radiometers which will be used in intensive operations this year with SCRIPPS, PML, and ORSTOM with additional US participation through the SIMBIOS project.
9. European Calibration/Validation Programmes
Dr. Schlittenhardt gave a brief overview of four of the major ocean-colour cal/val projects in Europe: i) CoASTS (Coastal Atmosphere and Sea Time Series) project aimed at collecting a two year time series of optical and bio-geochemical data in the North Adriatic Sea to support calibration and validation activities for MOS, SeaWiFS and OCTS; ii) CEVEx (Concertation on European Validation Experiments) for coastal/shelf water remote sensing, aimed at co-ordinating the already existing long term European calibration/validation projects such as PlyMBODY and CoASTS and to assess measurement strategies for the future; iii) COLOURS (Coastal Region Long-Term Measurements for Colour Remote Sensing Development and Validation), the objectives of which are to produce a time series of optical and bio-geochemical data for the major types of European coastal waters for the development and assessment of new bio-optical and atmospheric models/algorithms and; iv) COASTLOOC (Coastal Surveillance Through Observation of Ocean-Colour), the objectives of which include producing a large data set of the inherent optical properties of the main classes of optically active substances in European coastal waters for the establishment of new algorithms. In addition, Dr. Schlittenhardt drew attention to the new OCTOPUS (Ocean Colour Techniques for Observation, Processing and Utilization Systems) project, aimed at supporting and exploiting, in Europe, the present and upcoming missions of advanced optical sensors devoted to coastal and marine areas.
10. The SIMBIOS project
Dr. Mueller gave a presentation on NASA's SIMBIOS (Sensor Intercomparison and Merger for Biological and Interdisciplinary Oceanic Studies) project, which has the following aims: to quantify the relative accuracies of the products from international ocean colour missions, to improve the level of confidence and compatibility among the products and to generate merged, improved level-3 products. To date, there have been 17 funded SIMBIOS investigations, with annual science team meetings and technical focus workshops as well as instrument intercalibrations.
Following these presentations, considerable discussion ensued as to the role of the IOCCG in helping various projects realize their goals. It was concluded that the primary goal should be validation of existing sensors and that the IOCCG should help NASDA calibrate and validate the OCTS and POLDER sensors. Dr. Kawamura identified a need for ground truth data from various regions of the world for validation of the sensors, and Dr. Platt resolved to notify various international agencies such as the NSF (National Science Foundation) and IGBP (International Geosphere and Biosphere Programme) and request their co-operation in providing such data. It was also suggested that a technical workshop be held in 1998 to compare results from the POLDER, OCTS, MOS and SeaWiFS sensors.
11. Compatibility of Existing and Future Ocean Colour Sensors
Dr. Morel lead the discussion on the role of the IOCCG in proposing a minimum set of common channels to be included in all future ocean-colour sensors, so as to ensure continuity in ocean-colour measurements, to facilitate intercomparison between sensors and to allow compatibility of algorithms. After some discussion, Dr. Morel agreed to host a workshop, tentatively in the last week of September 1997, to determine the prospective ocean-colour user requirements and the technical requirements of the sensor. The workshop is to be funded by the IOCCG.
12. The Atlantic Meridional Transect (AMT) project
Dr. Aiken presented the latest results from the large-scale observational AMT project. The objectives of this programme are to collect optical and bio-optical data bi-annually along a transect from Britain to the Falkland Islands to support calibration and validation of the SeaWiFS sensor. A range of bio-geochemical, optical and bio-optical parameters are measured with the ship underway as well as from daily fixed stations. A wide range of bio-geochemical provinces are covered along this transect and much of the bio-optical variability between provinces was found to be driven by accessory pigments of phytoplankton, especially the ratio of photoprotective/non-photoprotective pigments.
13. Educational Materials Concerning Ocean-Colour
Dr. Platt proposed documenting lecture material (on a video tape or CD-ROM) dealing with the fundamentals and applications of ocean-colour data in order to broaden the expertise and increase the awareness and benefits of ocean-colour data. This material could be prepared by committee members or those outside the committee, and would require contributors to donate their time (approximately 1 day each). The tapes/CD's would then be distributed through the IOCCG at a minimal cost. There was a general consensus among the committee members for this proposal. In addition, Dr. Neumann pointed out that DLR was preparing a CD-ROM (in German and English) on ocean- colour to commemorate the anniversary of the MOS sensor, which should be ready for distribution by the next IOCCG meeting.
Dr. Frouin then drew attention to a proposal by Dr. Kopelevich (who was unable to attend the meeting), for an international cruise aimed at collecting bio-optical data and publicising the value of ocean-colour data through a series of lectures in various ports. The committee felt that this was an expensive proposition which could not be dealt with immediately, but Dr. Frouin agreed to follow up this issue with Dr. Kopelevich.
Dr. Lifermann also mentioned the ACE-2 campaign (Aerosol Characterization Experiment), an ESA funded programme aimed at determining the aerosol characteristics in Southern Europe (cruise goes from Portugal to Madeira, mid June to end July 1997) which also has the potential for international co-operation. This is an atmospheric ground based experiment, which would require supporting satellite data, so it would be a good opportunity for OCTS to process LAC data over that area for the specified time period.
14. Training Courses for Ocean-Colour
Dr. Platt drew attention to the first announcement for the Intensive Course on Remote Sensing of the Oceans. This course is to be held in Chile from 10 - 22 November, 1997 and will be sponsored primarily through the Inter-American Institute for Global Change Research (IAI). Preference will be given to participants from Latin America, but the IOCCG will make a contribution to enable people to attend who would not qualify for IAI funding. NASDA is also a sponsor of this course and will be sending a Japanese expert to demonstrate the new OCTS data.
Dr. Yoo urged the IOCCG to pay special attention to ocean-colour research in third world countries, especially SE Asia. Dr. Platt noted that the IOCCG could not help with expensive hardware facilities but could help with training, and Dr. Tanaka suggested that the IOCCG could perhaps organize an educational course in SE Asia next year. NASDA is making an I-LAC (intensive-local area coverage) archive available, which includes SE Asia.
In addition, Dr. Neumann pointed out that DLR had been receiving many requests for MOS data from Argentina, Brazil and Chile but these countries do not have receiving stations or the infrastructure to deal with the data. He agreed to keep the IOCCG informed on the progress in these areas.
15. Liaison between CEOS and IOCCG
One of the obligations of the IOCCG is to liaise with CEOS (Committee on Earth Observation Satellites) and in this regard Dr. Schlittenhardt gave a brief presentation on the activities of CEOS and its various working groups. He pointed out that the IOCCG could potentially interact with two working groups: the working group on calibration and validation (WGCV) and the working group on information systems and services (WGISS). In addition, Dr. Haruyama drew attention to the CEOS Analysis Group and the formation of the new IGOS (Integrated Global Observing Strategy) and SIT (Strategic Implementation Team) projects, conceived to promote rationalization of long-term ocean- colour measurements. Dr. Haruyama proposed that the Analysis Group interact with and complement the IOCCG and SIMBIOS as well as other affiliates such as GOOS, JGOFS, WGISS and OCTOPUS. Dr. Platt recommended that there be formal representation from the IOCCG to the Analysis Group as well as to the relevant entities of the CEOS working groups. Dr. Rast pointed out that he was already a member of a subgroup of WGCV.
16. Election of the Chairman
According to IOC regulations, Mr. Withrow raised the issue of election of the Chairman. Dr Yoder moved that Dr. Platt be re-elected by acclamation, and this proposal was so passed.
17. Time and Place of the Next Meeting and Closure
The group resolved to hold the next meeting sometime between October 1997 and January 1998. There being no further business, the meeting was adjourned. Dr. Platt thanked the staff of NASDA for hosting the meeting and for their assistance and co- operation in preparations for the meeting.