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Project Leader	Dr. Michael MANTON Bureau of Meteorology Research Centre 13th Floor 150 Lonsdale Street Melborne AUSTRALIA Tel: +61 3 9669 4444 Fax: +61 3 9669 4660 E-mail: m.manton@bom.gov.au
Funding	US$ 18,580
Participating countries	Australia, Fiji, French Polynesia, Indonesia, Japan, Malaysia, Myanmar, New Caledonia, New Zealand, Papua New Guinea, Philippines, Samoa, Solomon Islands, Thailand, Vietnam

Introduction/Background
Because of the broad community and political interest in the potential impact of the enhanced greenhouse effect on regional climate, there has been a focused international effort by the research community to collate and analyse climate data to identify and explain any trends or changes in climate over recent decades.  There has been a particular interest in trends in climate extemes, such as high temperatures and heavy rainfall, as these events can have a profound impact on all societies, as well as natural ecosystems.

In December 1998 the Asia Pacific Network for Global Change Research (APN) sponsored a workshop in Melbourne, Australia at the Bureau of Meteorology Research Centre (BMRC).  The workshop brought together scientists from 14 countries in the South East Asia - Western Pacific region to promote participation in the evolving international activities aimed at monitoring and detecting trends and changes in climate extremes.  A major recommendation of the workshop was that a second workshop should be held at which the participants could prepare an analysis of trends in climate extremes across the whole region.

Outline of activities conducted
The second APN workshop on trends in climate extremes was held in BMRC on 6-10 December 1999, with participation from the original 14 countries plus the Solomon Islands, along with significant contributions from the Bureau of Meteorology National Climate Centre and from CSIRO Atmospheric Research.  Each participant brought daily rainfall and temperature data for a few high-quality climate stations in their country for the period from 1961 to 1998.  Altogether, data from 91 stations were analysed.

Each participant first checked their data to ensure that they were homogeneous, having no jumps due to changes in site conditions or instrumentation.  The statistical techniques used to check for homogeneity had been introduced at the first APN workshop.  The data that passed the quality control checks were then analysed to determine trends in temperature and rainfall at each site.  Trends were examined for eight indicators:

-  frequency of daily rainfall exceeding the mean 99th percentile
-  average intensity of rainfall events greater than the mean 99th percentile
-  percentage of annual total rainfall from events greater than the mean 99th percentile
-  frequency of days with at least 2 mm rain
-  frequency of days with maximum temperature above the mean 99th percentile
-  frequency of days with minimum temperature above the mean 99th percentile
-  frequency of days with maximum temperature below the mean 1st percentile
-  frequency of days with minimum temperature below the mean 1st percentile

The quality control and analyses were carried out by participants using common software, so that the indicators were calculated consistently across the whole region.  Once the indicators were computed for each station, the participants first considered the results within their own countries.  Then the results were considered jointly across the whole region.

Towards the end of the week the participants drafted a scientific report summarising the results of the analysis.  The report was further refined and reviewed over the next few weeks.  It was submitted to a workshop of Working Group 1 of the Intergovernmental Panel on Climate Change (IPCC) in New Zealand in February for consideration in the IPCC Third Assessment Report.  At the same time, the report was submitted to an international journal for publication.  The report is co-authored by the 27 people involved in the workshop.

Outcomes/Products
The workshop has produced a number of valuable products.  Each participant received at the conclusion of the workshop a CD-ROM containing all the data from the participating countries, the software and documentation used for the quality control and analysis, all the indicators computed at the workshop, and the first draft of the workshop scientific report.

The main product of the workshop is the workshop scientific report.  This report, summarising the results of the analysis, has been submitted to an international journal for publication with 27 co-authors.  The report has also been passed to the convening lead authors of the observations chapter of the IPCC Third Assessment Report.  These scientists, Dr C. Folland from UK and Dr T. Karl from USA, have been directly involved in the process developed through the two APN workshops.  It is therefore expected that the results of the workshop will be incorporated in the IPCC report, although the results come late in the assessment cycle.

The key reason that the report will be used by the IPCC is that it has unique results, developed by a unique process.  We believe this is the first time that a regional group of countries has joined together to carry out a consistent analysis of climate data to examine the trends in climate extremes.  Thus, for the first time we have a broad and consistent picture of the trends in climate across the SE Asia - Western Pacific region.

Another outcome of the two APN workshops has been the creation of a network of scientists with a mutual interest in the analysis of climate data.  The indicators developed by the network are an important environmental resource for the region.

A measure of the significance of the workshop is highlighted by the observation that the process is being copied by other groups.  The World Climate Research Programme's CLIVAR program and the World Meteorological Organization's Commission for Climatology jointly sponsor a Working Group on Climate Change Detection (WGCCD).  The WGCCD has now decided to coordinate a series of regional capacity-building workshops designed to facilitate the development and exchange of climate indices.  The WGCCD recognises the APN workshop in Melbourne as the model to follow in organising this activity.

Future directions/follow-up work
The APN has established a benchmark process for the development of regional analyses of climate data.  It is expected that this process will be copied in other regions across the globe.  It is important that the APN maintains the momentum that it has now created in the Asia Pacific region.  In particular, it would be strategically significant to maintain the network of scientists that has been established through the two workshops.

A straightforward means of maintaining the network would be for the APN to establish a web page of the products and analyses of the network.  For example, the time series of the indicators developed at the 1999 workshop are a significant resource for the region that could readily be maintained on a central web site.

The success of the second workshop in 1999 encouraged all the participants to continue the work started by the analysis of the key climate stations in their countries.  As the participants are now familiar with the software used to quality control and analyse the data, it is feasible and desirable for them to conduct detailed analyses of much more of the climate data in their respective countries.  With the training provided by the initial workshops, future activities could be undertaken with much less intensive preparation.  In particular, it would be valuable to hold a further workshop (possibly in Kobe) at which the group would come together to compare the analysis of more extensive country data.  The main purpose of this analysis would be to confirm the results from the current activity which have been based on a relatively small amount of data.  With further examination of country data it should also be possible to extent the period of the time series analysis.

It is important to maintain the network of scientists so that regional analyses of the present and other indicators can be updated at regular intervals.  In particular, the IPCC is expected to maintain its series of regular climate assessments.  It will be necessary to ensure that the climate indicators for the Asia Pacific region are available for future IPCC assessments.

The two APN workshops have been taken as a model for the development of climate indicators in other regions of the world.  However, more importantly, it should be recognised that these workshops could be models for the development of a full range of environmental indicators.  Under the START and other regional capacity building projects, data on many aspects of the environment (i.e. physical, chemical, biological, ecological, economic and social) are being collected and analysed to some degree.  The benefits of these data collection activities would be greatly amplified if they were analysed systematically across regions and disciplines, through the development of essentially simple indicators of the environment.  Such indicators are key tools for policy makers, and it would be a significant role for the APN to lead the development of this process in the Asia Pacific region.