Things in this issue of the Bulletin
This issue starts with a report by Satish Shetye on the GLOSS-GOOS sea level training course at Dehra Dun, India last November-December. I can testify that this was one of the most successful GLOSS courses yet with excellent lectures from several people, effective 'hands on' computer training led by Pat Caldwell, and, most important of all, a good choice of participants. The Survey of India is to be thanked for making us all welcome. Meanwhile, planning is beginning for the next GLOSS training course, this time in Argentina at the end of 1996.
One of the participants was Teh Seng Hoe from Malaysia who has provided the second article in this issue. Malaysia has one of the most extensive sea level networks in S.E.Asia and has good quality data which should interest a lot of people. This is an excellent example of what the GLOSS training courses are trying to bring about.
One question that came up from the course was "Now that we have networks in many countries producing good data, why do we still have few people who know what to do with it?". For example, in the case of Malayisa, Teh tells me that there are few oceanographers who can inject expertise from their field. This situation seems to cry out for two things: graduate courses in universities linked to GLOSS-GOOS; and as much collaboration as possible with other countries.
This issue continues with a report by Aldo Drago of a MedGLOSS meeting last year which promises the development of sea level monitoring on a more coordinated basis in the Mediterranean region. The same file also contains a proposal for such a MedGLOSS network prepared by Dov Rosen and which was an input to that meeting. There are several proposals underway for enhanced sea level monitoring around Europe (EuroGLOSS, EPTN, NOSS) and MedGLOSS looks like being very complementary to those.
Then next we have a 'hello' from Mark Merrifield who has taken over from Gary Mitchum as Director of the Hawaii Sea Level Center following Gary's departure for Florida. (Swapping one tropical paradise for another perhaps). The contribution of Hawaii to sea level monitoring in recent years has been very great and we all look to Mark to continue the good work of Klaus Wyrtki and Gary.
Climate and sea level are intimately related and this issue contains two short summaries of studies of long term changes in global sea level. The first is the Executive Summary from Chapter 7 (Sea Level Change) of the Second Scientific Assessment of the Intergovernmental Panel on Climate Change (IPCC). This summary is meant to be an 'appertiser' for the full IPCC report which is full of information on all aspects of climate change and which will be essential reading for anyone interested in these subjects. (This report is from IPCC Working Group 1 on the Scientific Assessment. There is also sea level content in Working Group 2 regarding impacts etc. See http://www.usgcrp.gov/ipcc/).
The second summary is an abstract of a paper by Bruce Douglas for Surveys in Geophysics (reproduced here with the permission of the publishers) which updates his previous research published several years ago. Mail Bruce for a copy of the paper itself. Both these reviews conclude that sea level has indeed risen over the past century, while the IPCC report points to possible accelerations in the next which, although significant, are on average less than those suggested by previous working groups.
Prior to the 5th meeting of the GLOSS Group of Experts in early 97 (see below), we intend there to be a two day workshop on the theme of GPS fixing of tide gauge benchmarks. This topic has evolved considerably over the past few years with many countries now making GPS measurements. The meeting will be organised primarily by Ruth Neilan (Director of the IGS Central Bureau) who will make use in its planning of replies to a PSMSL/IGS circular letter (enclosed in this issue of the Bulletin ). WE WOULD BE GRATEFUL IF ANY GROUP MAKING GPS MEASUREMENTS AT TIDE GAUGE BENCHMARKS WHICH HAS NOT SO FAR RESPONDED TO OUR QUESTIONNAIRE COULD DO SO AS SOON AS POSSIBLE.
We have also included in this issue a link to POL's page on progress in making measurements of UK land movements by means of absolute gravity. Absolute gravity has been recognised as being capable of providing valuable information on land levels, complementary to those from GPS, and we would hope that this technique would also be represented at the workshop.
Two items of news are provided regarding Southern Ocean sea levels. The first by Marion Tait presents a status report of the Southern Ocean Sea Level Centre at Flinders University. The second is a short science report by Gregg Jacobs and colleagues on an apparent 4 year wave in Southern Ocean meteorology and therefore sea level, sea surface temperatures etc. I first heard a presentation of this work in May 95 at the TOPEX/POSIDON meeting at JPL and I was quite intrigued by it. Most of our tide gauge sea level records from the Southern Ocean are very short and it will be fascinating to see if they eventually show evidence for the wave.
Two items on ocean tides are also included included. The first, by Mike Smithson, gives a pointer to the IAPSO Pelagic Constants Dataset which Mike maintains on behalf of the PSMSL and IAPSO. The second is an announcement of a meeting on 'Tidal Science 96' at the Royal Society of London in October organised by Richard Ray and others. This meeting will celebrate the development of new, precise tide models, especially those stemming from TOPEX/POSEIDON data, and will review the geophysical applications to which new models may be put.
Finally, as in previous issues we include news of available sea level software. This time we have a report by Dov Rosen and Isaac Gertman on their ISRAMAR software system. Also, I can mention that at POL we have developed a PC package for tidal analysis and partial data quality control which we call TASK (Tidal Analysis Software Kit). This package is currently being 'alpha-tested' by a set of volunteers and, if we have not too many complaints, we should be able to make it available more widely in a couple of months. This package is meant to complement, rather than to be a competitor of, other packages already available from other centres.
Other news
Lesley Rickards has informed me that she has a new version of the GLOSS Handbook (Version 2.1) ready. This is being mailed out to all recipients of previous versions and additional copies can be sent to anyone interested (ljr@pol.ac.uk).
The number of Web pages with interesting sea level things continues to grow. Robin Tokmakian pointed me at http://vislab-www.nps.navy.mil/~rtt which contains her comparisons of sea level with results from the Semtner- Chervin model forced by real winds. The agreement is very encouraging and shows how useful gauges can be for model verification. Please take a look.
Also I can give some news of the next meeting of the GLOSS Group of Experts (GE) and the GLOSS Implementation Plan. Approximately every two years the GLOSS GE meets to review the status of the GLOSS network and associated projects and to plan for the future. The last meeting (the fourth) was at Bordeaux in January 1995. The fifth meeting of the Group (which is not a fixed set of people but has a flexible membership) is planned for March 1997 probably at the Jet Propulsion Laboratory in Pasadena, USA. This meeting will be more important than some of the previous ones as we intend to rewrite the GLOSS Implementation Plan over the (northern) summer so the new Plan can be discussed at the meeting. Please let us know if you have suggestions for things which should be included. The original Plan was written in the mid-1980's, although not published in final form until 1990. The new Plan will have to take into account the developments in satellite altimetry, GPS etc. over the last decade and, in essence, consider what GLOSS is now for and how scarse resources should best be used.
This will be the first GE meeting chaired by me and not by David Pugh who, along with Klaus Wyrtki and Albert Tolkatchev of course, has done more than anyone to turn GLOSS into a practical proposition. Since his move from Wormley to the brand-new Southampton Oceanography Centre, David has been reviewing his commitments and has decided to relinquish the driver's seat, although we all suspect he will be sitting behind the driver for some time yet.
Finally, Professor Afranio Rubens de Mesquita in Brazil informs me that a third issue is now available of the Afro-America GLOSS News . The GLOSS Bulletin is just one of two "newsletters" about GLOSS and related activities. While the Bulletin is in electronic form, the Afro-America GLOSS News is avaliable on paper with most articles in Spanish and Portuguese. If you would like a copy of the latter, mail ardmesqu@fox.cce.usp.br.
Many thanks to the contributors to this third issue. Happy reading!
Philip Woodworth plw@pol.ac.uk