PSMSL Annual Report for 1998

1. Introduction

This report reviews briefly the work of the Permanent Service for Mean Sea Level (PSMSL) during 1998. This year the PSMSL has data banked a record amount of sea level information, has taken a major role in the development of the Global Sea Level Observing System (GLOSS), and has contributed to important international working groups on climate change and geophysics.

2. PSMSL Data Receipts for 1998

In the period since the last Annual Report (i.e. since mid-December 1997), over 2500 station-years of data were entered into the PSMSL database. This record amount of information, comparable to that entered in the previous record year of 1996, was received from the countries listed in Appendix 1 and from locations plotted in Figure 1. In particular, large numbers of station-years, including several sets of national data backlogs and a number of newly acquired long time series, were obtained from Finland, Spain, Ukraine, Russia, Australia, Chile and the USA. The most gratifying aspect of Figure 1 is the evidence that data are now received routinely from almost all parts of the world, aside from parts of Africa and South America. This agreeable development has arisen partly thanks to the availability of electronic mail and fax in almost all agencies with which the PSMSL maintains contact (see Section 3.11 below). Elaine Spencer, PSMSL Technical Secretary, is to be congratulated on a considerable amount of hard work in acquiring, checking and data banking the record amount of information.

3. GLOSS Activities

The Global Sea Level Observing System (GLOSS) is an Intergovernmental Oceanographic Commission (IOC) project, one of the aims of which is to improve the quality and quantity of data supplied to the PSMSL. GLOSS can be considered as one of the first components of the Global Ocean Observing System (GOOS).

3.1 GLOSS Status from a PSMSL Viewpoint (October 1998)

For the last few years, usually coinciding with a GLOSS GE meeting, the PSMSL has provided a summary of the status of GLOSS from its viewpoint. This summary has usually been made in October so as not to bias the statistics because of the seasonal cycle of data receipts.

An 'operational' station from a PSMSL viewpoint means that recent Mean Sea Level (MSL) monthly and annual values have been received at Bidston, have been checked as far as possible, and have been included in the databank. For each of the GLOSS stations, we have used the year of the last data entered into the databank, if any, to place the station into one of four categories:

Category 1: 'Operational' stations for which the latest data is 1994 or later;
Category 2: 'Probably operational' stations for which the latest data is within the period 1984-1993;
Category 3: 'Historical' stations for which the latest data is earlier than 1984;
Category 4: For which no PSMSL data exist.

Table 1 lists the numbers of stations which fall into each category for all stations, while Figure 2 shows their locations. Also shown in Table 1 are the numbers in each category reported previously with the category definitions adjusted backwards one, two, three etc. years appropriately. Note that before 1993 we used the 'GLOSS90' definition of GLOSS (306 stations total), whereas 1993 onwards we have used 'GLOSS93' (308 stations total). We don't believe that change modified the statistics to a great extent. Also note that from 1997 we have used the 'GLOSS97' definition of GLOSS (287 stations total).

Overall, the statistics for 1998 are similar to those for 1997 indicating ongoing work is required to develop the network even further.

                            Table 1
        Number of Stations in Each Category (1989-1998) 

 Cat.     89    90    91    92    93    94    95    96    97    97    98

   1     105   133   136   158   177   183   168   186   183   182   183
   2      51    50    57    46    33    35    59    46    48    47    48
   3      47    42    36    29    26    26    22    21    23    17    20
   4     103    81    77    73    72    64    59    55    54    41    36

Total    306   306   306   306   308   308   308   308   308   287   287

using 'GLOSS Definition'
         90     90    90    90    93    93    93    93    93    97    97
3.2 GLOSS Operational and Non-Operational Stations Survey (December 1998)

In December, a detailed survey was conducted of the 287 stations of the 'GLOSS Core Network' (GCN) to determine which gauges were operational or not as of February, the deadline for receipts of questionnaire replies from national authorities as part of 'GLOSS Handbook' updating. The replies were supplemented by 'PSMSL general knowledge' in the case of non-replies.

Of the 287 sites in the GCN (defined by 'GLOSS97'), only 42 are claimed to non-operational. This set is listed in Appendix 2 and plotted in Figure 3. It is clear that action must be taken by national authorities to instrument the sites in order to complete the network. If national resources are limited, the authorities should be endeavouring to install equipment through bi-lateral links or possibly by making requests for second-hand equipment through IOC (see Section 3.5 below). Alternatively, if a site cannot feasibly be instrumented, perhaps owing to environmental conditions, then IOC should be notified so that it can be reviewed for removal from the definition of the GCN at the next revision of the network.

3.3 Reconciliation of the Statistics of Sections 3.1 and 3.2

It is clear that Figure 3 presents a more optimistic view of GLOSS status than does Figure 2, a situation which requires investigation. One reason is that at some 'operational' locations (e.g. Tristan da Cunha and some Antarctic sites), the gauges take the form of simple pressure transducers which provide useful information for oceanography (e.g. for the World Ocean Circulation Experiment) but which do not supply MSL data, as conventionally defined, which can subsequently be submitted to the PSMSL. This situation is understandable and tolerable if there are good environmental or technical reasons for such a choice of technology.

However, a second reason is that while an 'operational' gauge might exist and be providing data of some kind, the expertise or facilities or manpower do not exist in order to process those data routinely and deliver them to the international community. This situation is not an acceptable one, as it clearly requires some kind of investment in hardware, software or training. The job of IOC/GLOSS (and to some extent of the PSMSL) is to remedy such situations as far as possible.

3.4 GLOSS Training Course 1998

A training course for ten sea level scientists from different parts of Africa and from Brazil, and for a similar number of 'local' South Africans, was held at the University of Cape Town during 16-27 November, hosted by Prof.Geoff Brundrit and Dr.Howard Waldron of the Oceanography Department. Drs. Woodworth and Baker from the Proudman Oceanographic Laboratory (Bidston Observatory) and Mme.Janice Trotte, GLOSS Technical Secretary at IOC, were guest lecturers. The main themes of the course concerned background sea level science (climate change, oceanography), the need for related geodetic measurements, and hands on training sessions' (HOTS). The opportunity was taken to also discuss plans for action in east, south and west Africa as part of GLOSS and of the Global Ocean Observing System (GOOS) for Africa. This was a very successful course, for which a workshop report will shortly be available containing extensive reviews of status in each participating country.

3.5 Requests for New Resources for GLOSS

IOC funds for GLOSS are extremely limited and tend to be devoted to the costs of meetings (e.g. those of the GLOSS Group of Experts), training courses (e.g. the University of Cape Town course) and sea level products (e.g. data and training CD-ROMs). There are virtually no funds for new gauges or geodetic equipment.

Two courses of action were initiated in 1998 in order to try to find new resources for GLOSS. First, letters have been written to international companies (e.g. oil companies) with interests in certain parts of the world for which GLOSS developments are required. The letters asked if interest exists in the companies to sponsor the training and/or provision of hardware to a young scientist, perhaps via a master's course at a UK university. At the time of writing, it is too early to judge the success of such appeals. If any reader of this document has suggestions on possible recipients of such letters, the PSMSL would be grateful to know of them.

Second, a request for second-hand, but serviceable, tide gauge hardware was circulated by the PSMSL in 1998, and relayed to the correspondence list of the International Hydrographic Organisation (IHO). This resulted in the offer of 4 good gauges from Singapore, and the possibility of offers of others. This single kind donation from Singapore to GLOSS will result in at least two African countries (Madagascar and one or two others) having 'new' gauges in 1999. The PSMSL and IHO intend to repeat the request in the near future.

3.6 GLOSS Publications

Issue 6 of the GLOSS Bulletin was published on the web during 1998 and can be found at:

Meanwhile, the next issue of the Afro-America GLOSS News is in preparation by the University of Sao Paulo (USP) in Brazil.

3.7 GLOSS Handbook and the WOCE Sea Level CD-ROM

In preparation for the International World Ocean Circulation Experiment (WOCE) conference in Halifax, Canada in May 1998, the PSMSL and British Oceanographic Data Centre (BODC) began work in January on a new CD-ROM which contains the WOCE Sea Level Centre data sets, together with an updated version of the GLOSS Handbook, and the PSMSL data set. The PSMSL was represented at the Conference by Dr.Vassie and Mr.Axe. Copies of the CD-ROM have been distributed widely, and some extra copies are still available. In addition, the updated GLOSS Handbook entries can be inspected via the web at:

and any scientist with updated information to provide, or comments to make on particular sites, is invited to contact the PSMSL. A new set of questionnaires will be circulated to GLOSS Contacts early in 1999, and the web pages updated yet again as soon as possible thereafter.

3.8 GLOSS Brochure

An updated two page brochure advertising GLOSS has been produced by Gillian Spencer and Robert Smith. Two thousand copies have been printed for circulation in the UK and we hope that GLOSS National and Regional Contacts will arrange for printing in their own countries. Copies of the files which make up the brochure (Corel Draw files) may be sent to anyone interested who can edit and adapt them according to local interests.

3.9 After GLOSS: GLOUP

Many people interested in tide gauges and altimetry will also be interested in bottom pressure measurements. Dr.Hughes from POL has recently taken a lead in trying to get global bottom pressure measurements and data sets on a better footing, providing potentially a component of GOOS parallel to GLOSS. He calls this activity GLOUP. For more information, see:

A meeting connected to GLOUP will be held in April 1999 at the Royal Society organised by Dr.Hughes and Prof.Carl Wunsch from MIT.

3.10 GLOSS Meetings

Full meetings of the GLOSS Group of Experts (GGE) take place at approximately two-yearly intervals. However, it is our intention that international collaboration will be enhanced by holding regional meetings in intervening years whenever possible. Consequently, a regional GLOSS meeting was held on 20 July at the Academia Sinica, Taiwan hosted by Prof.Shui-Beih Yu, in association with a meeting of the sea level group of the Asia Pacific Space Geodynamics project led by Prof.C.K.Shum from Ohio State University. The meeting benefitted from the attendance of many scientists at the Western Pacific Geophysics Meeting in Taiwan the following week. Further information on the GLOSS meeting can be found at:

Planning is now in an advanced stage for the sixth meeting of the GGE during 10-14 May 1999 at the Laboratoire d'Etudes en Geophysique et Oceanographie Spatiales in Toulouse, kindly hosted by Dr.Christian Le Provost. The GGE meeting itself will take up 12-14 May but we intend to use the 10-11 for a special workshop on 'Ocean Circulation Science derived from the Atlantic, Indian and Arctic Sea Level Networks' to be held under the auspices of IOC/GLOSS and IAPSO and with convenor Dr.Gary Mitchum from the University of South Florida. One purpose of the workshop is to highlight the important science which can be performed using sea level data from the Atlantic, Indian and Arctic Oceans and, thereby, to point to requirements for sea level measurements in the future. We concentrate on these areas in particular as several excellent workshops have been already been held on the Pacific and Southern Oceans by IOC and IAPSO in recent years, and as these three ocean areas could require (depending on the science requirements) relatively greater investment in instrumentation than they have had in the past.

We also intend that there will be a GLOSS meeting at the IUGG in Birmingham in July 1999, probably held in association with the IAPSO Commission on MSL and Tides. Dr.Woodworth will be a co-convenor for two sea level sessions at the Birmingham conference.

3.11 GLOSS Email Survey

All GLOSS Contacts can now be reached via electronic mail except for those from the following countries. If email addresses exist which we are not familiar with, we would be very grateful for the information:

Angola, Bangladesh, Cameroon, People's Republic of China, Congo, Djibouti, El Salvador, Fiji, Guinea, Haiti, Indonesia, Jamaica, North Korea, Madagascar, Mauritania, Mexico, Morocco, Myanmar (Burma), Panama, Sao Tome & Principe, Sierra Leone, Somalia, Sri Lanka, Tanzania, Thailand, Trinidad & Tobago, Uruguay and Yemen.

3.12 GLOSS Forward Look

It is interesting that during the year under review that the most senior of the world's politicians were evidently doing good work on our behalf. At the Fourth Session of the 'UN Framework Convention on Climate Change, Conference of the Parties' in Buenos Aires 2-13 November, the following recommendations of the Subsidiary Body for Scientific and Technological Advice were approved (amongst others). Such recommendations could have been written with the PSMSL and GLOSS in mind, and give the highest possible lead to national authorities to provide the international community with the sea level and other data sets which it needs for research. When considered alongside the approval of the new GLOSS Implementation Plan by the IOC Assembly in 1997, GLOSS can be seen to, in principle, have the highest level backing in which to perform its work in coming years:

3.12 Temporary GLOSS Technical Secretary

Following the retirement of Dr.Tolkatchev from IOC in 1997, and the reorganisation of the GOOS Office in Paris following the appointment of new Director, Dr.Colin Summerhayes, the role of GLOSS Technical Secretary has been occupied part-time until the end of 1998 by Mme.Janice Trotte from the Directoria de Hidrografia e Navegacao (DHN) in Brazil. Janice's work for GLOSS, and indirectly for the PSMSL, is very much appreciated. From January 1999, the position will be filled by a new appointment at IOC, although contact with Janice will be maintained through her ongoing work for GOOS.

4. TASK-2000

The PSMSL/POL Tidal Analysis Software Kit (TASK) has been extended and updated during 1998, particularly with regard to year 2000 compliance. The package was used intensively during the HOTS sessions at the Cape Town course and is available free to any university or research institute scientist. A small fee will be charged to commercial users.


The third scientific assessment of the Intergovernmental Panel on Climate Change (IPCC) commenced with a meeting in Bad Munstereifel, Germany at the end of the June and with a first drafting session in Paris in December. At the Bad Munstereifel meeting, there was considerable discussion as to whether there should be a dedicated sea level chapter and working group, as for the second assessment. In the end, the conclusion was that there should be, and the following people were eventually delegated to act as Lead Authors:

John Church         CSIRO Marine Research, Australia (Joint Coordinator)
Jonathan Gregory    Hadley Centre, UK (Joint Coordinator)
Philippe Huybrechts Free University of Brussels, Belgium
Michael Kuhn        University of Innsbruck, Austria
Kurt Lambeck        Australian National University
Dahe Qin            Chinese Academy of Sciences
Philip Woodworth    Proudman Oceanographic Laboratory, UK and PSMSL

The latter's role in this is, of course, to provide some linkage to GLOSS and the PSMSL. Any input to the editing work to be performed by these Lead Authors over the next year or so will be much appreciated.

The December IPCC meeting was followed by the International CLIVAR (Climate Variability and Prediction) Conference, also held in Paris. Dr.Woodworth represented the PSMSL and was also a member of the UK delegation at this conference.


The European Union EOSS project (formerly called NOSS) aims to enhance sea level (tide gauges) and land level (GPS) monitoring, and associated data exchange, in Europe primarily by sets of bilateral (i.e. no new cost) agreements. First activities in this five year project have centred around the North Sea, where most of the countries which have so far signed up to the project commitments are located. Mr.Axe from PSMSL/POL has taken the lead in informing the EOSS group of the activities in GLOSS and in leading 'Work Package 5' which is associated with data exchange issues. Mrs.Spencer and Drs.Baker and Woodworth have also contributed to EOSS activities during the year. It is to be hoped that EOSS will result in the more reliable provision of sea and land level information from the European region. More information on EOSS can be obtained at:

7. Altimetry and Gravity Field Activities

Participation has continued in European and US altimeter working groups. Drs.Woodworth and Hughes became Principal Investigators during the year for the JASON (TOPEX/POSEIDON Follow On) mission during the year, and an application for Co-Investigator status for the Envisat mission is pending with the European Space Agency (ESA). In April-May, POL and Liverpool University hosted a meeting of the British Group of Altimeter Specialists (BGAS).

Dr.Woodworth attended a number of meetings through the year as a member of the Mission Advisory Group (MAG) of the ESA 'Gravity Field and Steady State Ocean Circulation Experiment (GOCE)' mission, which is now near the end of the Phase-A development stage. The provision of a more precise model of the Earth's gravity field and geoid is of great importance to a range of oceanographic and geophysical studies.

8. Other Relevant Meetings

The following relevant meetings were attended during the year, in addition to those discussed above:

February-March:     Workshop to Develop an Implementation Action Plan for GOOS
March:              Visit to the Australian National Tidal Facility
July:               Visit to Hong Kong Polytechnic University (for APSG)
September:          'Gravity Day' at ESTEC/ESA, Netherlands
October:            Symposium to mark the retirement of Prof.Vidal Ashkenazi,
                    University of Nottingham, UK
November:           Interim Advisory Group for GOOS meeting, Met‚o-France, Paris

9. Publicity

Open Days took place at POL (including PSMSL) during 16-19 July and were attended by 2000 members of the public as well as local dignitaries and Members of Parliament. In addition, one Cabinet Minister and one Junior Minister attended at a later date.

The PSMSL/GLOSS benefited later in 1998 from a high public exposure related to a 'Climate Change in the UK' report issued by the Hadley Centre and University of East Anglia in which past and future sea level was discussed in some detail. (Discussion followed largely that of the second IPCC scientific assessment.) An article describing the work of the PSMSL appeared in the Liverpool Echo. Subsequently, Mr.Alcock represented the PSMSL at a 'Climate Change in the NW England meeting in December'.

In November the work of the PSMSL was featured in a programme on the second German TV network (ZDF).

10. Visitors to the PSMSL in 1998

In April, a delegation of experts from Viet Nam visited the PSMSL with regard to upgrades of the national tide gauge network. The delegation included Dr.Dao Chi Cuong (Vice Chairman and Chief of Cartography, Hydrographic Bureau of Viet Nam), Prof.Pham Hoang Lan (Dean, University of Mining and Geology), Mr.Nguyen Nguyen Cuong (Senior Expert, Department of Environment, Ministry of Science, Technology and Environment), Dr.Nguyen The Tuong, (Director, National Hydrometeorological Center), Mr.Luu Truong De (Senior Expert, Department of Science, Ministry of Science, Technology and Environment) and Dr.Bui Xuan Thong (Research Scientist, Marine Hydrometeorological Center).

Other visitors to the PSMSL during 1998 included Prof.J.McGlade (Director, Centre for the Coastal and Marine Sciences of which POL and PSMSL form parts), Drs.J.Gregory and J.Lowe (Hadley Centre, UK), Dr.S.Shackley (University of Manchester Institute of Science and Technology, UK), Dr.G.Andre (Military Survey, UK), Drs.Dougal Goodman and James Orr (British Antarctic Survey).

11. Published Reports following the 1997 PSMSL Annual Report

The 1997 PSMSL Annual Report referred to a number of important reports in preparation which have now moved to the 'published' or 'in press' stage. These are listed in Appendix 3.


It can be seen that 1998 has been a further active year with regard to important workshops and conferences, and a busy one with regard to data acquisition and analysis.

Particular thanks as usual go to Mrs.Elaine Spencer (PSMSL Secretary) and to members of staff of the Proudman Oceanographic Laboratory (Bidston Observatory) who contribute part of their time to PSMSL activities.

P.L.Woodworth (December 1998)

Appendix 1: Number of station-years entered into the databank for each country or coastline in the period mid-December 1997 to mid-December 1998 (2557 total).

 ICELAND                     2
 FAEROE ISLANDS              4
 SPITSBERGEN                 2
 NORWAY                     22
 SWEDEN                     17
 FINLAND                   130
 POLAND                      5
 DENMARK                    55
 GERMANY (NORTH SEA)        26
 NETHERLANDS                11
 UNITED KINGDOM             42
 IRELAND                     3
 CHANNEL ISLANDS             1
 FRANCE (ATLANTIC)          30
 SPAIN (ATLANTIC)           11
 PORTUGAL                   42
 ITALY (ADRIATIC)            1
 SLOVENIA                    7
 GREECE                     17
 ROMANIA                    63
 UKRAINE                   114
 GEORGIA                     7
 TURKEY                      4
 SPANISH N. AFRICA           1
 PORTUGAL (AZORES)          18
 PORTUGAL (MADEIRA)          5
 SENEGAL                     2
 ASCENSION                   2
 NIGERIA                     2
 ST. HELENA                  2
 SOUTH AFRICA               10
 MOZAMBIQUE                  9
 CROZET IS.                  3
 KERGUELEN ISLAND            6
 SAINT PAUL ISLAND           5
 SEYCHELLES                  2
 MAURITIUS                   4
 MALDIVES                   10
 TANZANIA                    2
 KENYA                       5
 GULF                        3
 MUSCAT & OMAN               4
 INDIA                      25
 VIETNAM                     1
 CHINA                      33
 HONG KONG, CHINA            8
 TAIWAN (FORMOSA)            9
 KOREA (SOUTH)              83
 JAPAN (HOKKAIDO)           14
 JAPAN (SHIKOKU)            15
 JAPAN (KYUSHU)             19
 JAPAN (AMAMI GUNTO)         5
 PAPUA NEW GUINEA            8
 AUSTRALIA                 355
 GUAM                        2
 PALAU ISLANDS               2
 NAURU                       2
 MARSHALL ISLANDS           10
 KIRIBATI                    7
 TUVALU                      6
 SOLOMON ISLANDS             1
 NEW CALEDONIA              18
 VANUATU                     4
 FIJI                        7
 TONGA                       4
 AMERICAN SAMOA              2
 WESTERN SAMOA              22
 HAWAIIAN ISLANDS           16
 LINE ISLANDS                5
 PENRHYN ISLAND              2
 ILES DE LA SOCIETE          1
 COOK ISLANDS                6
 MARQUESAS                   3
 GAMBIER ISLAND              2
 EASTER ISLAND               4
 USA (ALASKA)               31
 USA (PACIFIC COAST)        40
 MEXICO (PACIFIC)           19
 PANAMA (PACIFIC)            3
 COLOMBIA (PACIFIC)          2
 ECUADOR                     8
 PERU                       16
 CHILE                      62
 ARGENTINA                   7
 BRAZIL                      2
 GUADELOUPE                  4
 MEXICO (GULF)               1
 CUBA                        2
 PUERTO RICO                 4
 VIRGIN ISLANDS              4
 USA (GULF)                 53
 BERMUDA                     2
 USA (ATLANTIC)             69
 GREENLAND                   4
 ANTARCTICA                 14

Appendix 2: Non-Operational GLOSS Sites

GLOSS No. GLOSS Station                 Responsible Country

 262      LOBITO                        ANGOLA                 
 190      PUERTO DESEADO                ARGENTINA              
  47      CHRISTMAS IS.                 AUSTRALIA              
 197      PORTO DE NATAL                BRAZIL                
 153      LITTLE CORNWALLIS IS.         CANADA                 
 224      NAIN                          CANADA                 
 261      POINTE NOIRE                  CONGO                    
 166      I. DEL COCO                   COSTA RICA            
 227      DANMARKSHAVN, GREENLAND       DENMARK            
   2      DJIBOUTI                      DJIBOUTI                
 182      ACAJUTLA                      EL SALVADOR            
 165      CLIPPERTON IS.                FRANCE                   
  21      CROZET IS.                    FRANCE                   
 131      DUMONT D'URVILLE              FRANCE                
 204      LE ROBERT,  MARTINIQUE        FRANCE                 
  24      ST. PAUL IS.                  FRANCE                   
 209      PORT-AU-PRINCE/LES GAYES      HAITI                    
  41      NICOBAR                       INDIA                 
  67      SORONG                        INDONESIA             
 240      CASTLETOWNSEND                IRELAND                  
 252      NOUADHIBOU (CAP BLANC)        MAURITANIA            
 160      ISLA GUADALUPE                MEXICO                 
 282      TAN TAN                       MOROCCO               
 141      MOULMEIN                      MYANMAR                
 128      CHATHAM IS.                   NEW ZEALAND         
 134      SCOTT BASE                    NEW ZEALAND
 232      BJORNOYA (BEAR ISLAND)        NORWAY                
 295      GWADAR                        PAKISTAN              
 272      DARU                          PAPUA NEW GUINEA      
  64      VANIMO                        PAPUA NEW GUINEA      
  25      MIRNY (ANTARCTICA)            RUSSIA                
 260      SAO TOME                      SAO TOME/PRINCIPE        
 256      ABERDEEN POINT                SIERRA LEONE          
   6      HAFUN (DANTE)                 SOMALIA               
   7      MOGADISHU                     SOMALIA               
  20      MARION IS.                    SOUTH AFRICA          
   9      MTWARA                        TANZANIA                 
 303      MASSACRE BAY,ATTU IS.,ALASKA  U.S.A.                   
 218      MIAMI (HAULOVER PIER)         U.S.A.                   
   3      ADEN                          YEMEN, P.D.R.          
 304      SOCOTRA IS.                   YEMEN, P.D.R. 

Appendix 3: Some Reports Now 'In Press' Referred to in the 1997 Annual Report

Woodworth, P.L. (ed.) 1997. Global Sea Level Observing System (GLOSS) implementation plan-1997. Intergovernmental Oceanographic Commission, Technical Series, No. 50, 91pp. & Annexes.

Ray, R.D. and Woodworth, P.L.1997. Preface to the Special Issue on Tidal Science. Progress in Oceanography, 40(1-4), 1-6.

International Sea Level Workshop held at the University of Hawaii, 10-11 June, 1997. Published by the National Oceanic and Atmospheric Administration. 133pp.

Baker, T.F., Woodworth, P.L., Blewitt, G. Boucher, C. and Woppelmann, G. 1997. A European network for sea level and coastal land level monitoring. Journal of Marine Systems, 13, 163-171.

Woodworth, P.L. 1997. The Global Sea Level Observing System (GLOSS). GOOS News No.4, November 1997, pp.7-8. Published by the Intergovernmental Oceanographic Commission.

Woodworth, P.L. 1997. The Permanent Service for Mean Sea Level and the Global Sea Level Observing System. pp.55-62 in, Science Services. International Association of Geodesy (IAG) & Federation of Astronomical and Geophysical Services (FAGS). Presented at the IAG Scientific Assembly, Rio de Janeiro, Brazil, September 3-9, 1997. Published jointly by the Department of Civil and Environmental Engineering and Geodetic Science, The Ohio State University, Columbus, Ohio and the IAG Central Bureau, Department of Geophysics, University of Copenhagen, Denmark.

Neilan, R., Van Scoy, P.A. and Woodworth, P.L. (eds). 1998. Proceedings of the workshop on methods for monitoring sea level: GPS and tide gauge benchmark monitoring and GPS altimeter calibration. Workshop organised by the IGS and PSMSL, Jet Propulsion Laboratory, 17-18 March 1997. 202pp.

Woodworth, P.L., Tsimplis, M.N., Flather, R.A. and Shennan, I. 1998. A review of the trends observed in British Isles mean sea level data measured by tide gauges. Geophysical Journal International (in press).

Alcock, G.A. and Woodworth, P.L. (organisers). 1998. Joint IOC-CIESM training workshop on sea-level observations and analysis for the countries of the Mediterranean and Black Seas. Proudman Oceanographic Laboratory, 16-27 June, 1997. Intergovernmental Oceanographic Commission Workshop Report No.133.

Balmino, G., Perosanz, F., Rummel, R., Sneeuw, N., Sunkel, H. and Woodworth. P. 1998. European views on dedicated gravity field missions: GRACE and GOCE. European Space Agency Report ESD-MAG-REP-CON-001. 66pp.