New Zealand Climate Committee

Report on the International CLIVAR Conference, Paris, 2-4 December 1998

John W. Kidson

National Contact for CLIVAR, New Zealand Climate Committee

Introduction

CLIVAR, the Climate Variability and Predictability programme, has become the primary research component of the World Climate Research Programme (WCRP) directed towards improved climate forecasting and understanding of anthropogenic effects. It focuses on the role of the coupled ocean and atmosphere within the overall climate system, with emphasis on variability on seasonal to centennial timescales. It is an important programme that will coordinate much international climate research over the next 15 years. It follows on from the successful TOGA (Tropical Ocean Global Atmosphere) and WOCE (World Ocean Circulation Experiment) programmes and takes up the further scientific challenges they have identified.

CLIVAR will support new observational programmes and the enhancement of coupled ocean-atmosphere models to improve understanding of climate variability, leading to development of new global and regional forecast models. New Zealand is significantly affected by El Niño - Southern Oscillation (ENSO) events and recent press releases from NIWA and other CRIs highlight the role of the recently-discovered Pacific Decadal Oscillation in changing New Zealand’s climate over the past 20 years. Planned CLIVAR sub-programmes will give emphasis to these phenomena, which originate in the tropical Pacific, but little attention has so far been given to the extratropical variability in Southern Hemisphere, which also significantly effects New Zealand.

To advance the planning and begin the implementation of CLIVAR, the WCRP sponsors, namely WMO, ICSU and IOC, held a major international Conference on CLIVAR at UNESCO Headquarters, Paris, France from 2-4 December 1998. Approximately 200-250 delegates from 60 countries attended.

Dr Kidson of NIWA was nominated by the RSNZ Climate Committee to represent New Zealand and present its national report. It was hoped that he would be able to promote more effort on understanding and predicting variability in the extratropical Southern Hemisphere. His travel was funded from MoRST through the ISAT/TPP programme.

Meeting programme

A copy of the programme for the meeting is appended. The first day was devoted to addresses outlining the role of CLIVAR within the WCRP and reviewing the scientific successes of its predecessor, the TOGA programme, and presentation of the scientific issues to be examined within CLIVAR. A summary of the keynote addresses and the national presentations will be included in the conference proceedings, which will be available in about 6 months.

Many of the ideas presented are discussed in the draft plan and in other material available on the CLIVAR web site at http://www.dkrz.de/clivar/hp.html

The second day was reserved for presentations from around 35 of the national delegations. National Reports had previously been circulated in printed form and it was intended that delegates review the CLIVAR plan and outline the contributions they would make to it. The New Zealand report and presentation highlighted the need for more effort to be applied to understanding and predicting mid-latitude and Southern Hemisphere phenomena, and the contributions relating to climate modelling and ocean observations which we are prepared to make.

On the final day a panel provided answers to questions about the scope, direction and management of CLIVAR, the points raised in the national presentations were reviewed, and further keynote addresses presented. The final meeting statement is appended.

Issues relating to Science and Technology Policy

1. Organisation of the CLIVAR programme

Initial planning for CLIVAR has been performed on a somewhat informal, cooperative basis by individual scientists. It appears likely that an inter-governmental panel will be set up to administer it in the future, although the form that this would take was not discussed. The arrangements may be similar to those for the preceding TOGA programme in which New Zealand participated. It seems likely that liaison with the panel on organisational matters would be the responsibility of MoRST and MFAT, but that scientific issues would continue to be dealt with by the Royal Society’s New Zealand Climate Committee. It is not expected that the inter-governmental liaison will require a lot of time or effort, but it is likely to involve occasional attendance at overseas meetings. Some monetary contribution to the work of the International CLIVAR Project Office (ICPO) may be expected in future but it has few staff and any future NZ contribution is likely to be small. Costs of the ICPO are currently met by a few countries, including the United Kingdom where it is now located.

2. New Zealand contributions to CLIVAR

The New Zealand contributions to CLIVAR, as set out in the National Report, include further climate modelling and palæoclimate studies, and monitoring of the major ocean currents which pass near New Zealand. While the first two areas can be funded by existing or planned PGSF programmes, ocean monitoring work is less easy to accommodate. It requires long time series of oceanic observations obtained through research voyages, moorings, and the manufacture and deployment of floats and drifters (which travel at up to 2000m depth to measure low-level currents and provide vertical profiles of temperature and salinity as they rise to the surface every 14 days). Some ocean monitoring forms a valid part of PGSF programmes as it provides measurements of value within New Zealand’s EEZ. However, contributions to routine global monitoring on the high seas probably require other sources of funding. There is strong scientific justification for this extra funding as it likely to lead to better understanding and prediction of decadal-scale fluctuations in the climate, such as the "climate shift" described by NIWA and other CRIs earlier this year.

Other extraordinary contributions to the work of CLIVAR might be expected from time to time when special field programmes requiring extensive observation gathering are mounted. None are included in the initial plans for CLIVAR. Typically these programmes utilise ocean research vessels and funding for New Zealand participation would fall outside the normal FRST allocations. The costs for a New Zealand research vessel to participate in a month-long experiment could run to $1M.

Other matters of interest to New Zealand

• The absence of Principal Research Areas covering mid-latitude and Southern Hemisphere variability on the seasonal to interannual timescale was of particular concern to New Zealand. Increased skill in seasonal forecasting will require better prediction of ENSO, but it is also strongly dependent on better knowledge and prediction of extra-tropical phenomena. The New Zealand national report and presentation at the meeting helped shape a decision by the Scientific Steering Group to reconsider whether more attention should be given to these areas in the CLIVAR plan. The outcome will not be known for some time but we are hopeful of some success.

• Monitoring of the Pacific Ocean was to be extended by the USA to cover the belt between 30ºN and 30ºS in a new Pacific Basin Extended Climate Study (PBECS). Offers of assistance from other countries around the Pacific rim, including New Zealand, were instrumental in a decision to extend PBECS to cover the entire Pacific Basin. While scientific outcomes are not always predictable, we would expect this enhanced observational programme to lead to significant advances in the knowledge and forecasting of decadal-scale oscillations.

• Palæoclimate studies will provide an important source of data for studying climate variations on decadal to centennial time scales. Interest centres particularly on the last 400 years in order to extend the data series used to study decadal oscillations. Input of palæoclimate data to CLIVAR is by way of the PAGES project of the IGBP. New Zealand palæo scientists wishing to contribute to CLIVAR will need to register their projects with PAGES and ensure that they obtain estimates of climate elements which can be used directly for empirical studies and model validation.

• Dr Kevin Trenberth, a New Zealand scientist working in the USA, is co-chair of the Scientific Steering Group which has developed the CLIVAR plan and will now be working on its implementation. He will be visiting New Zealand in February 1999, and while in Wellington will be able to make a presentation about the goals and implementation of CLIVAR that should be of wide interest.

Assessment of the need for future participation

There is unlikely to be a similar meeting for a number of years. The priority over the next few years will be to develop the plans for the research sub-programmes in the light of the promises made in Paris. This will be done by a number of panels with representatives from interested countries. Quite probably we will want to be represented on one or more, to try and ensure that they include work of relevance to New Zealand. (I have already been asked by Kevin Trenberth if I would like to serve on one.) Hopefully most of the business of these panels can be conducted by email, but there may be the need to attend one or two meetings per year, mostly in the Northern Hemisphere, or to hold the occasional small meeting in New Zealand. A budget of $5-10,000 annually for this type of activity should be ample.

Scientific meetings will be held from time to time to review progress but normal institutional funding should meet the costs of participation.

CLIVAR is an important programme, which promises to bring significant benefits to New Zealand over its 15-year lifetime. It relies on voluntary contributions from individual countries for its success and we should support it to the best of our ability.