Draft Version of
26 February 1999

PSMSL Report to the GE6 Meeting

Report of PSMSL Activities to the Sixth Session
of the GLOSS Group of Experts

P.L.Woodworth
Permanent Service for Mean Sea Level
Proudman Oceanographic Laboratory, Bidston Observatory,
Birkenhead, Merseyside L43 7RA, U.K.

1. Introduction

This report reviews briefly the work of the Permanent Service for Mean Sea Level (PSMSL) during 1997-98. Many of the PSMSL's GLOSS-related activities in this period have already been covered in the Chairman's Report to the GE6 meeting. In this short note, other aspects of interest from the PSMSL Annual Reports of the last two years are reviewed briefly. GLOSS is important to the PSMSL in that one of the stated main aims of the programme is to improve the quantity and quality of data supplied to the Service.

2. PSMSL Data Receipts for 1997-98

In the period 1997-98 over 3300 station-years of data were entered into the PSMSL database. This record amount of information was received from the countries shown in

http://www.pol.ac.uk/psmsl/anrep97.figure1.gif (data receipts for 1997)and

http://www.pol.ac.uk/psmsl/anrep98.fig1.gif (data receipts for 1998)

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 the figures 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. 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. 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 POL 1997 and Cape Town 1998 training courses and is available free to any university or research institute scientist. A small fee will be charged to commercial users.

4. IPCC TAR

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 1998 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. I represented the PSMSL and was also a member of the UK delegation at this conference.

5. EOSS

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. Philip 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. Philip has also attended all twice-yearly Management Meetings. In addition, Elaine Spencer, Trevor Baker and myself have contributed to EOSS activities during the period. 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:

http://www.pol.ac.uk/psmsl/eoss/eoss.html

6. Altimetry and Gravity Field Activities

Participation has continued in European and US altimeter working groups. Chris Hughes and I became Principal Investigators for the JASON (TOPEX/POSEIDON Follow On) mission during the period, while I obtained Co-Investigator status for the Envisat mission of the European Space Agency (ESA). In April-May 1998, POL and Liverpool University hosted a meeting of the British Group of Altimeter Specialists (BGAS).

A number of meetings were attended through 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.

7. After GLOSS: GLOUP

Many people interested in tide gauges and altimetry will also be interested in bottom pressure measurements. Chris 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:

http://www.pol.ac.uk/psmsl/gloup/gloup.html

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

8. Relevant Meetings

The following relevant meetings were attended during 1997-98, in addition to those discussed above. More information on each meeting can be found in the PSMSL Annual Reports:

March 1997:         PSMSL/IGS Workshop at Jet Propulsion Laboratory, USA 
April:              European Sea Level Workshop at Barcelona 
May:                UK Sea Level Workshop in London
June:               International Sea Level Workshop in Hawaii, USA
July:               IAG Conference at Rio de Janeiro
                    (PSMSL represented by Prof.A.R.de Mesquita)
October:            Ocean Data Symposium in Dublin
                    (PSMSL represented by Dr.Lesley Rickards)
October:            TOPEX/POSEIDON and Ocean Monitoring Meeting in Biarritz
December:           EOSS Management Committee at Copenhagen

Feb-March 1998:     Workshop to Develop an Implementation Action Plan for GOOS
                    in Sydney, Australia
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, Meteo-France, Paris

9. Tidal Science '96

A meeting entitled Tidal Science '96 was held at the Royal Society in October of that year. During 1998, papers stemming from the meeting were published in a special issue of Progress in Oceanography, with Richard Ray (Goddard Space Flight Center) and myself acting as editors.

10. Publicity

Open Days took place at POL (including PSMSL) during 16-19 July 1998 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, Graham 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).

11. PSMSL/WOCE Centre Staffing

The PSMSL was joined at the start of 1997 by Philip Axe from the University of Plymouth. Philip has recently finished his Ph.D studies on coastal processes in the south of England and is currently completing his thesis. His main duties at the PSMSL and WOCE Centre include the bringing up to date of several WOCE-related sea level data sets, overlaps with the various European and global GPS/tide gauge activities, and of course scientific analysis of the data.

Summary

It can be seen that 1997-98 has been a further active period with regard to important workshops and conferences, and a busy one with regard to data acquisition and analysis.

Particular thanks as usual go to Elaine Spencer who has been PSMSL Technical since 1974. The PSMSL is very much her data set. Unfortunately, both Elaine and her husband Bob, who will be well known to a number of GLOSS people though his deployments of tide gauges and bottom pressure recorders, have decided to take early retirement in May 1999. I am sure that the sincere thanks and best wishes of the GLOSS community will be extended to them both.

P.L.Woodworth (March 1999)