TAO Home About the TAO project Data display pages Data access El Niño and La Niña information Site map
TAO Proceedings - TIP 9
Proceedings of the ninth session of the TAO Implementation Panel (TIP-9)

Perth, Australia, 16-17 November 2000

Edited by
Michael J. McPhaden
NOAA/Pacific Marine Environmental Laboratory
7600 Sand Point Way NE
Seattle, Washington 98115-0070
January, 2001

Table of Contents

  1. Introduction
  2. Current Conditions
  3. Operational Analyses and Forecasting
  4. Status of the TAO/TRITON Array
  6. Ship-of -Opportunity Program
  7. NOAA Climate Observing Program
  8. Indian Ocean
  9. Review of Tropical Moored Buoy Programs
  10. Dissolution of the Panel
  11. Acknowledgments
    Appendix - Meeting Attendees

1. Introduction
The ninth session of the TAO Implementation Panel (TIP-9) was held at the West Australian Department of Commerce and Trade in Perth, Australia on 16-17 November 2000. The meeting was convened with the assistance of the local organizing committee for the Workshop on Sustained

Other TIP pages
TIP homepage
TIP-7, Ivory Coast, November 1998
TIP-8, France, November 1999
Observations for Climate of the Indian Ocean (SOCIO), which was held earlier in the week in Perth. The purposes of TIP-9 were to review the present status of the TAO/TRITON array; to address technical and logistic issues related to its maintenance; and to provide a forum for discussion of enhancements and expansions of the array for climate studies. The Panel also addressed specific issues related to the design and development of a moored buoy program for Indian Ocean climate studies, following on the recommendations of the SOCIO meeting. Representatives from the US, Japan, Australia, Mauritius, and South Africa were in attendance. Written input was provided by panel members from India and France.

2. Current Conditions
TAO/TRITON data indicate that La Nina conditions have waned since early 2000. At present, weak cool SST anomalies generally less than 1C are found in the eastern Pacific and weak warm anomalies generally less than 0.5C are found in the warm pool region of the western Pacific. Subsurface anomalies of 1-2C are found in the upper 200 m resulting from a stronger downward tilt to the equatorial thermocline. The structure of the subsurface anomalies (warm in the west, cool in the east) is similar to that which existed in December 1996 before the last El Nino.

The latest NCEP coupled model project forecast (as of November 7) indicates a warming trend over the next three seasons, with development of 1C anomalies in the eastern equatorial Pacific. Other statistical and dynamical ENSO forecast models also show weak warming trends, though most do not indicate development of significant warm SST anomalies. Considering the range of forecasts over the next several seasons, the likelihood is that near neutral conditions will prevail in the tropical Pacific in the coming year.

3. Operational Analyses and Forecasting
Ming Ji of NOAA/NCEP reported on the uses of TAO/TRITON data in operational analyses and forecasting. TAO/TRITON data are used at NCEP, ECMWF, and elsewhere for operational climate monitoring, and for initialization of coupled ocean-atmosphere forecast models used in operational ENSO and seasonal climate forecasting. Ji also noted that salinity variations on seasonal-to-interannual time scale are pronounced in the western equatorial Pacific. Although real-time salinity observations at present are very limited, NCEP has developed techniques to use TAO/TRITON subsurface temperature data and satellite altimetry data to derive pseudo-salinity data and assimilate both temperature and salinity data into the ocean model for improved ocean analyses. The new NCEP ocean data assimilation system is capable of assimilating both temperature and salinity from TAO/TRITON and from future ARGO floats. NCEP plans to produce operational global ocean analysis which assimilate both temperature and salinity based on real-time TAO/TRITON observations in the near future.

4. Status of TAO/TRITON Array

4.1 Designation of the array as TAO/TRITON
As of 1 January 2000, the TAO array officially became known as the TAO/TRITON array in recognition of the fact that JAMSTEC has assumed responsibility for maintaining sites along 156E, 147E, and 138E in the western Pacific with TRITON moorings. Wind, SST, air temperature, relative humidity, and subsurface temperature from ATLAS and TRITON buoys are transmitted on the GTS and have been merged into a unified data set available on the World Wide Web at PMEL (/tao/) and a mirror site in Japan (http://www.jamstec.go.jp/jamstec/TRITON). Prior to withdrawal of ATLAS moorings from the western Pacific, several 6-8 month overlapping ATLAS and TRITON time series were collected from collocated moorings to ensure the comparability and consistency of data from the two mooring systems

4.2 Shiptime
For calendar year 2000, 384 days at sea were required to support the TAO/TRITON array. NOAA ships (Ka'imimoana, Ron Brown) accounted for 275 days, JAMSTEC ships (Kaiyo, Mirai) accounted for 108 days. The French RV Alis contributed one day in April 2000 to recover the mooring from 2N, 165E which had broken free from its anchor. Shiptime use anticipated in 2001 is similar to that in 2000.

4.3 ATLAS data return
Real-time daily averaged data return for ATLAS moorings between 95W and 165E was 89% for the 12 month period October 1999 to September 2000. Data return by variable was 88% for wind, 93% for air temperature, 95% for relative humidity, 88% for sea surface temperature, and 88% for subsurface temperature.

4.4 Vandalism
Vandalism continues to plague the TAO/TRITON array in the Pacific and the PIRATA array in the Atlantic. Data return is significantly lower in regions of high tuna catch in the eastern and western Pacific, and in the eastern Atlantic. In addition, over the past three years (October 1997-September 2000), 17 of 220 ATLAS moorings deployed in the Pacific between 95W and 137E broke free from their anchors and drifted away from their deployment sites. Of these, 9 systems disappeared while 8 partial systems were later recovered. While not all of these losses can be attributed to vandalism, physical evidence from recovered systems suggests it is a major contributor. In addition, of 10 TRITON moorings deployed between 138E and 156E in the past year, 9 showed signs of vandalism, though fortunately no TRITON buoys were completely lost.

Efforts to combat vandalism continue, though it is not clear they are making much impact. These efforts included distribution of information brochures to national fishing agencies, fishing boats in ports of call, and industry representatives. Also, presentations on the effects of vandalism were made in the past year in Martinique (International Fish Aggregation Device Conference, September 1999), Lake Arrowhead, California (Inter-American Tropical Tuna Commission, May 2000), and Monaco (International Hydrographic Organization, June 2000). Engineering efforts to make moorings more robust and vandal-resistant are under development as well.

4.5 TRITON deployment schedule revisions
The schedule for TRITON deployments in the western Pacific between 130E, 138E, and 147E has been revised because of problems with vandalism. Sites along these meridians will be occupied at a slower pace than originally planned in the coming year. Deployments will take place at 2N and 5N, 147E in March 2001, and along 130E and 138E in October-November 2001.

Planned deployments of TRITON buoys in November at 0, 90E and 5S, 95E in the Indian Ocean were cancelled, though subsurface ADCP moorings were deployed by the Mirai at these locations. Indian Ocean TRITON deployments have been rescheduled for November 2001. Concerns about possible strong current drag on the equatorial buoy were raised when a TRITON buoy deployed in the Kuroshio Extension dragged its anchor dangerously close to a submarine communications cable earlier this year. Engineering efforts to reduce drag on TRITON moorings will be undertaken prior to Indian Ocean deployments in 2001.

4.6 TRITON salinity
Postprocessing of TRITON salinity data from Seabird Microcats for first deployments in the western Pacific Ocean indicate drifts over 1 year of 0.065 psu on average in the upper 100 m and 0.034 psu on average between 125-200 m. Sensor drift was much smaller between 250-750 m. Drifts in the upper 200 m were towards higher salinity, consistent with the effects of mechanical scouring of the conductivity cell as described in earlier Seabird Seacat deployments on ATLAS moorings in the western Pacific. These drifts may be correctable by applying a combination of pre- and post-deployment calibrations.

The importance of surface and subsurface salinity data was emphasized by analysis of TRITON data showing approximately 2.5-4.5 cm RMS errors in dynamic height of the sea surface relative to 500 db when salinity is not taken into account.

4.7 Eastern Pacific Investigation of Climate (EPIC)
NOAA's EPIC program has undertaken an enhancement and extension of the TAO/TRITON array along 95W for the 4-year period 1999-2003. The purpose of this enhanced monitoring effort is to provide a comprehensive set of oceanic and meteorological data to support descriptive, diagnostic, and modeling studies of coupled ocean-atmosphere interactions in the ITCZ, cold tongue and stratus deck regions of the eastern tropical Pacific. This enhanced monitoring array will also provide the context for a process-oriented field studies to take place in August-September 2001.

Additional ATLAS moorings were added to the 95W line at 3.5N, 10N, and 12N in the past year. All moorings along this meridian are equipped with shortwave radiation, longwave radiation, barometric pressure, and rainfall sensors in addition to the usual suite of meteorological instrumentation. Also, these moorings include salinity at 7 depths in the upper 120 m and current at 1 to 2 depths in the upper 40 m. These new measurements will allow for accurate computation of surface heat, moisture, and momentum fluxes, as well as the local oceanic response to those fluxes. The data will also facilitate studies of atmospheric boundary layer dynamics . All measurements (with the exception of salinity at three depths) are now available in real-time as daily averages. Barometric pressure will soon be added to the GTS data stream. Two ATLAS moorings in the ITCZ have been instrumented with experimental acoustic raingauges as test of that technology for long term moored buoy applications. A WHOI IMET mooring deployed at 20ÚS, 85ÚW extends the ATLAS line southward into the stratus deck region off the west coast of South America.

As noted in Section 4.4, problems with vandalism are affecting ATLAS data and equipment return along 95W.

4.8 Woods Hole Oceanographic Institute Intercomparison Study
Recognizing that TRITON, ATLAS and IMET meteorological data will be used extensively for climate studies in the future, a specially designed land-based intercomparison study was conducted at Woods Hole Oceanographic Institute in May-June, 2000. The purpose of this study was to establish the comparabilty of meteorological measurements made by the various systems when placed in very close proximity to one another. Preliminary results can be viewed on the web at /tao/epic/whoitests.shtml

4.9 New TAO project web pages
The TAO project updated the content and functionality of its web pages this past year. The new pages provide easier access to TAO/TRITON (and PIRATA) data sets, as well as a updated technical information on buoy systems, sensor accuracies, sampling characteristics, and graphical displays. These pages can be found at /tao/

4.10 TAO/TRITON array support
The US (NOAA), Japan (JAMSTEC), and France (IRD) currently support the TAO/TRITON array through contributions of shiptime, equipment, and technical support. Additional support in the US is provided by NASA's TRMM program for rainfall measurements at various sites throughout the basin, and by DOE's ARM program for shortwave radiation along 165E.

Taiwan, through National Taiwan University, had until recently also provided support for the array. Though Taiwan is no longer actively involved in the field program, its contributions of shiptime and an ATLAS mooring were critical to the successful implementation of the TAO array during and just after TOGA. The Panel acknowledged the importance of these contributions, and cited Drs. David Tang and Huang-Hsiung Hsu of National Taiwan University for their leadership in service to TAO.

5. Pilot Research Moored Array in the Tropical Atlantic (PIRATA)

PIRATA, which is jointly sponsored by France, Brazil, and the US, will transition to a 5-year "consolidation" phase intended to run from 2001 to 2006. The consolidation phase will allow time for demonstrating the utility of PIRATA data in climate forecasting and applications. Success during the consolidation phase the array could lead to consideration of PIRATA as a permanent feature of the global ocean observing system and global climate observing system.

Array design for the consolidation phase has been modified to eliminate two ATLAS sites (2N and 2S, 10W) where intense fishing vandalism has significantly limited data and equipment return. These two sites are not critical for achieving the basic objectives of the PIRATA field program, and their elimination should improve overall data return which has been only 69% for the 3-year period October 1997 to September 2000.

This year, NOAA funded an extension of PIRATA in the northwest basin with a Woods Hole flux mooring to be deployed in April 2001 at 16N, 51W. Other possible extensions in the next few years are under discussion for the northeast, southeast, and southwest tropical Atlantic, with support from countries bordering these regions.

An international conference tentatively scheduled for September 2001 in Paris will consider implementation of an integrated satellite and in situ climate observing system in the tropical Atlantic Ocean in support of CLIVAR, GOOS, and GCOS. PIRATA figures to be a key element of that observing system.

6. Ship-of-Opportunity Program (SOOP)

Rick Bailey, chair of SOOP Implementation Panel (SOOPIP), gave a presentation on the status and future directions of the Ship-of-Opportunity Program (SOOP). More details on SOOP are available at http://www.brest.ird.fr/soopip/. Around 100 merchant vessels presently record upper ocean thermal data (down to 800m) on selected, routinely repeated lines covering most of the ocean basins. Several of the time series go back decades, and provide in some areas such as the Indian Ocean some of the only sustained observations of the upper ocean. These data in general complement other in situ and remotely sensed data in support of operational (such as seasonal-to-interannual climate forecasts) and research applications. In recent years there has been a rapid expansion in the use of merchant vessels for the collection of interdisciplinary observations, such as surface and subsurface salinity, pCO2, surface fluxes, phytoplankton and zooplankton distributions, and upper ocean currents. This suite of observations will coordinated with other observational programs, such as TAO, under the CLIVAR Ocean Observations Panel (COOP) and the Observations Program of JCOMM.

During 1999, the OOPC, CLIVAR UOP and SOOPIP sponsored a review of the global XBT network in light of the most recent scientific objectives of the network, and taking into account the existence and advent of other in situ and remote sensing observing systems such as TAO, profiling floats, and altimeters. A background study was supported by NOAA's Office of Global Program (OGP), Australian Bureau of Meteorology, and CSIRO Marine Research. From the workshop and background a revised XBT network with unique contributions to the globally integrated ocean observing system was proposed. The new primary focus is on frequently repeated line sampling in the tropical oceans, coupled with high-density eddy-resolving sections spanning the major gyres and boundary currents to help resolve the ocean transport of mass, heat and salt. The broadcast low-density XBT sampling, which is presently used to mainly monitor heat content, is to be ceased once and only if the Argo profiling float program is fully implemented and proven successful.

7. NOAA Climate Observing Program

Sidney Thurston, NOAA Office of Global Programs, presented an implementation plan for NOAA's contribution to the ocean component of the global climate observing system. The mission of the Climate Observing Program is to build and maintain global observing networks needed to satisfy the long-term requirements of the operational forecast centers, international research programs, and the major climate assessments. National and international partnerships are essential to success of this climate observing program. The implementation strategy, therefore, is based on an extension of the building blocks that are in place, and on the international plan drafted by over 300 scientists from 26 nations that met in Saint Raphael, France in October, 1999 (the OCEANOBS 99 Conference).
NOAA will build the Climate Observing Program within the context of a proposed end-to-end Climate Services initiative, which will also contribute to marine services. Within this framework, the Program will consider the requirements for understanding the earth's climate system, and the global water and carbon cycles.

A global observing system by definition crosses international boundaries. The way the observing systems projects are organized, implemented and managed will reflect this. The Program will foster a "systems" approach to effective international organization of complementary in-situ, satellite, data and modeling components of climate observations. The systems approach to development will start in 2000 with an "initial system" of 12 well-rationalized networks. As knowledge increases, the Program will evolve over a phased 10-year implementation period by building each of these networks with specific milestones and performance measures (deliverables). Implementation will proceed while attempting to closely adhere to the "Ten Climate Monitoring Principles" recently described in the 1999 Nation Research Council report "Adequacy of Climate Observing Systems".

8. Indian Ocean

The SOCIO meeting earlier in the week provided a backdrop for TAO Panel discussions of a sustained Indian Ocean observing system for climate. SOCIO reviewed scientific issues relating to the Asian-Australian monsoons, intraseasonal variations, the Indian Ocean diplole, ENSO interactions, and other climatically relevant phenomena in the Indian Ocean. SOCIO also reviewed ongoing and planned satellite and in situ observational activities in the Indian Ocean to address these issues. The Indian Ocean is the least well observed of the three tropical basins, and is one area where new ocean measurements would have not only great scientific value, but potentially great societal value as well.

Views at expressed at SOCIO with regard to ocean observations were consistent with those put forward at OceanObs99 in San Raphael in October 1999, but with some new and slightly different emphases, particularly with regard to shorter time scales. These emphases included process studies of diurnal to intraseasonal time scale variations (needed for seasonal prediction), heightened emphasis on flux measurements, heightened emphasis on hydrological cycle and a crucial need for salinity, and the need for both fixed-point time series and broad scale basin coverage. Ocean state estimation emerged as a crucial under-pinning strategy for societal and science issues. Some augmentation of the GODAE strategy would be needed to address the shorter time scales important for the Indian Ocean. Implementation of Argo in the next few years will be a major step forward, but Argo will not provide high temporal resolution data or surface fluxes in the near equatorial region where rapid oceanic and atmospheric variations occur, and where ocean-atmosphere coupling is strong. The emphasis on shorter time scales and new fields (fluxes, salinity) lead specifically to a recommendation for a mooring array.

Moored buoys are ideally suited for providing critical data sets in this region, and therefore a valuable complement to other satellite and in situ measurement efforts. At present, there are 12 moored meteorological buoys deployed in the Arabian Sea, Bay of Bengal, and the EEZ of India under auspices of the Indian National Data Buoy Program. Three subsurface current meter moorings are presently deployed on or near the equator by JAMSTEC and the Indian National Institute for Oceanography. The number, instrument payloads, and distribution of these moorings however is inadequate for the purposes of providing basin scale coverage in support of climate forecasting and analyses.

Recognizing that there is great potential societal benefit to developing an integrated, sustained, basin scale ocean observing system in the Indian Ocean for climate purposes, and that a moored buoy program like that in the Atlantic and Pacific Oceans would be a valuable component of such an observing system, the TAO Panel recommends that priority be given to the design and implementation of an Indian Ocean moored buoy array within the context of CLIVAR, GOOS, and GCOS. The Panel further recommends that an ad hoc working group be established to develop a science and implementation plan based on our current understanding of climate variability and predictability in the region. This group should be formed within the next year and should consist of representatives from nations interested in contributing resources to the development and maintenance of such an array. In addition, the panel strongly endorses the Western Indian Marine Applications Project (WIMAP) initiative lead by South Africa and Mauritius, and the JAMSTEC initiative to deploy TRITON buoys at 0, 90E and 5S, 95E, as critical building blocks for the successful development of a basin scale moored buoy array.

9. Review of Tropical Moored Buoy Programs

Tropical moored buoy programs in support of climate research, forecasting, and ocean state estimation will undergo review at an international workshop to be held at the Pacific Marine Environmental Laboratory in Seattle, Washington during the week of 10-14 September 2001. The purpose of the review will be to document the utility of moored time series data for climate studies, to identify strengths and weaknesses in existing programs, and to provide advice on possible enhancements, extensions, or modifications to those programs. It is anticipated that the meeting will be co-sponsored by the WRCP, CLIVAR, GOOS, and GCOS.

10. Dissolution of the Panel

Based on discussions over the past year with its parent bodies, the Panel dissolved itself at the conclusion of TIP-9. In a strict sense, the original mandate of the panel covered implementation and maintenance of the Pacific moored buoy array through a multi-national partnerships. However, a Pacific focus to a moored buoy panel was viewed as too narrow in view of ongoing and planned programs in all three tropical oceans. There is also a need to consider capacity building in many countries with an interest, but limited capability, to participate in moored buoy programs. Finally, the panel's heavy involvement in scientific program planning, as required during the formative stages of TAO array development, is no longer urgently needed, since many other CLIVAR committees have this mandate.

With the dissolution of the existing TIP, a new Tropical Moored Buoy Implementation Panel (also referred to as TIP) will be inaugurated under auspices of CLIVAR, GOOS, and GCOS in the coming year. New terms of reference will expand the scope of this panel to the global tropics, with emphasis on technical and logistic issues related to implementing and sustaining buoy programs in support of climate studies.

11. Acknowledgments

The Panel wishes to acknowledge the IOC Perth Regional Office and the West Australian Department of Commerce and Trade for hosting TIP-9. Special thanks to Bill Erb of IOC, and Gary Meyers and Bronwyn Marshall of CSIRO, for their help with the many details involved in convening TIP in Perth. The panel is also grateful for the financial support of IOC/GOOS, and for the administrative assistance of Art Alexiou of IOC. The TAO Implementation Panel is sponsored by IOC/GOOS, GCOS, and International CLIVAR.

Appendix Meeting Attendees

Art Alexiou, IOC/UNESCO, France
Rick Bailey, CSIRO, Australia
Graeme Brough, Bureau of Meteorology, Australia
Bill Erb, IOC/Perth, Australia
Stuart Godfrey, CSIRO, Australia
Peter Hacker, University of Hawaii, USA
Mark Jury, University of Zululand, South Africa
Yoshifumi Kuroda, JAMSTEC, Japan
Kunio Kutsuwada, Tokai University, Japan
Mike Manton, Bureau of Meteorology, Australia
Mike McPhaden, NOAA/PMEL, USA
Gary Meyers, CSIRO, Australia
Phil Parker, Bureau of Meteorology, Australia
Steve Piotrowicz, NOAA/OAR, USA
S. Ragoonaden, Meteorological Service, Mauritius
Dwi Susanto, Lamont Doherty Earth Observatory, USA
Sidney Thurston, NOAA/OGP, USA


Home | Project overview | Data display | Data delivery | El Niño & La Niña | Site map

TAO Project Office
| Pacific Marine Environmental Laboratory
7600 Sand Point Way NE
Seattle, WA 981
Credits | Disclaimer | Privacy Policy