Southeast Asia is a region with important and unique sensitivities to climate variability and change. Many countries in this region have developed climate change projection scenarios to feed national adaptation plans. Numerous uncertainties and challenges are associated with downscaling global climate projections to the national level; various methods exist to represent and communicate these uncertainties to end-users. The diversity of methodological approaches to produce downscaled climate change projections reflects the wide range in technical expertise, capacity, resources, stakeholder needs, organizational structure and external collaborations/partnerships amongst the ASEAN Member States.
The Best Practice Workshop for Climate Change Projections and their Application in ASEAN Countries was the first of its kind to review the various climate projection studies for the region. Its aim was to define guidelines, not only in the generation of downscaled projections, but also in the use of these projections by decision-makers in their planning for potential climate-related vulnerabilities. The development of recommendations for best practice requires a holistic approach beyond national efforts to produce climate change projections and facilitate the coordination and integration of regional climate change projection efforts, in particular the World Climate Research Programme (WCRP)’s supported CORDEX initiative, which in the region (CORDEX-SEA) is gathering place amongst academia.
Objectives of the Workshop
The Workshop held in Singapore from 20 – 23 March 2018 was organised by the Centre for Climate Research Singapore (CCRS), the research arm of the Meteorological Services Singapore (MSS) as host of the ASEAN Specialised Meteorological Centre (ASMC). Aims of the Workshop were to (1) review existing methodologies in the development and use of regional climate change projections for national-level adaptation planning across ASEAN Member States, (2) review cross boundaries initiative across Southeast Asian , (3) assess key regional scientific challenge in the generation of these projections, (4) evaluate the uptake of these projections by the Vulnerability and Impact Assessment (VIA) community across the region and (5) brainstorm across the diverse workshop attendance in order to propose recommendations toward the definitions of best practices.
The Workshop saw the participation of (1) representatives from the National Meteorological and Hydrological Services (NMHSs) of 9 ASEAN Member States (Cambodia, Indonesia, Lao PDR, Malaysia, Myanmar, Philippines, Singapore, Thailand, and Vietnam), (2) international experts from UKMO, CSIRO, and BoM, along with regional experts from the CORDEX-SEA community, and from Singapore institutions (CCRS, TMSI, EOS), (3) representatives from regional end-users of climate projections, including the AHA Centre, ICRISAT, GWP-Indonesia, the Mekong River Commission, and RIMES as well as representative from the Pacific Island region.
Format of the Workshop
The Workshop comprised a series of presentations and two break-up discussion sessions.
The Workshop opened with presentations by ASEAN and Pacific Island NMHSs on the methodology employed in the production of national climate change projections, followed by presentations by regional and international experts on the scientific achievements and challenges in delivering climate projections and climate services for the region. End-users from the impact community also presented on the challenges in the use of climate projection information for adaptation planning.
In the first break-up discussion session, participants were divided into groups to ensure diverse sectorial representation and therefore encourage cross-sectorial dialogue. Discussions were framed around 2 main topics:
- Climate change science, with a focus on the usefulness, limitations and future challenges specific to the Southeast Asian region
- Use of climate projections for adaptation planning, with a focus on the usefulness, limitations and future challenges specific to the Southeast Asian region
In the second break-up discussion session, Participants were divided into 4 groups based on sectorial expertise to enable more focused discussion on recommended guidelines. Discussions were framed around 3 topics:
- Guidelines on generating climate projections for the region, including recommended strategies to improve quality and coverage of projection information for Southeast Asia
- Guidelines on using projections in planning and policy development, including recommended strategies for improving national and regional cross-sectorial collaborative links
- Guidelines on maximising benefits from future developments in climate change science
Break-up discussions on Day 2 and 3 of the Workshop.
Consensus recommendations from the Workshop and detailed meeting notes will be consolidated into a Meeting Report (drafting in progress; to be uploaded by end of June 2018). A summary of key issues identified during the Workshop is presented below.
The workshop highlighted the diversity of methodological approaches to producing downscaled climate projections for policy planning. This reflects the wide range of technical expertise, capacity, resources, stakeholder needs, organizational structure, and external collaborations/partnerships amongst the Member States. Notwithstanding the width of technical complexity in the delivery of climate change projections, it was noted that a critical element for success is the early and sustained engagement with stakeholders and intended end-users to ‘co-produce’ tailored climate products and foster a mutual understanding of model limitations and uncertainties. The quality of the work was achieved by working closely with end-users across a number of regional projects. Lessons have been learnt and systematic sharing of these lessons and best-practices would be benefit the region. For example, the workshop reviewed work targeting the agricultural sector (by the International Crops Research Institute for the Semi-Arid Tropics, ICRISAT), river basin management (by the Mekong River Commission, MRC), and city water management (by the Public Utility Board, PUB, Singapore).
At this point in time, not all ASEAN NMHSs are equipped to provide dedicated climate projection services. Hence, developing guidance materials on the synthesis and use of climate projections for impact studies, particularly with regards to the systematic treatment and communication of uncertainties, was identified as a top priority for the region. Sustaining cross-sectorial knowledge exchange, for example through training workshops, remains a challenge, in part due to national/organisational funding constraints. These constraints could be alleviated if the projections and scientific analyses produced by the CORDEX-SEA initiative and other regional level initiatives like SEACAM were generalised and better consolidated. They were found to be highly valuable in supporting Global Climate Model (GCMs) selections, Regional Climate Models (RCMs) evaluations, and the generation of national climate change projections to ensure a full utilisation of climate change information by the VIA community.
Amongst the many technical difficulties encountered during the delivery of climate change projections, some important issues surfaced during the discussions: (1) standardisation of the GCM selection criteria and (2) downscaling methodologies. These were seen as essential across the region to consolidate the current wealth of regional climate change information. For the first point, there is a need for quantitative model evaluation metrics, complemented with process studies to understand the sources of model biases and limitations. For the second point, while dynamical downscaling (the use of RCMs) is prevalent, statistical downscaling methods are also used across the region, given the variety of free-to-use analysis software such as SimCLIM. However, guidance is necessary to evaluate how statistical methods compare to dynamically-downscaled projections. End-users were also supportive of improving observational data networks to better constrain climate variability. For many of these issues, it was suggested that in order for the community to make progress together, a series of scientific papers with a large authorship list from regional scientists should be completed on some of the key issues: comparisons of existing gridded data across Southeast Asia to validate models, important regional climate processes that climate models need to capture, and feedbacks on interaction with end-users of climate change projections.
Participants also recognised that much more could be done to advertise climate data already available for the region, remove barriers to data access, and share them across operational environments. Beyond sharing of climate data, participants also welcomed sharing of case studies of successful collaborations within ASEAN to identify strategies that could be readily adapted across political landscapes. Given the uneven distribution of technical expertise in the region, participants called for the establishment of a regional scientific authority to provide guidance on the generation and usage of climate models. Representatives from PACCSAP (Pacific-Australia Climate Change Science Adaptation Planning) informed on the success of the regional consortium approach to delivering climate change projections for the Pacific island region, and workshop participants were very supportive of adapting a similar framework for the ASEAN region. It was noted that currently support for climate change projections is either based on a structured top-down driver of a national initiative or is organically supported from a bottom-up approach driven by knowledge expansion. A mechanism to ensure the long-term viability across ASEAN member countries of a complete community (NMHSs, Academia, and VIA community) does not exist at this point in time for this important endeavour to generate actionable climate change information in support of and in partnership with the VIA community across the region.