03 OCT 2022
ASEANCOF
Recap of the Eighteenth Session of the ASEAN Climate Outlook Forum (Online, PAGASA)
Introduction
The Eighteenth Session of the ASEAN Climate Outlook Forum (ASEANCOF-18) was organised by the Philippine Atmospheric, Geophysical, and Astronomical Services Administration (PAGASA) in collaboration with the ASEAN Specialised Meteorological Centre (ASMC) and the ASEANCOF Working Group. Participants from the NMHSs of ASEAN Member States created a consensus forecast for the boreal summer monsoon 2022 in the ASEAN region.
Participants from NMHSs, WMO-RAP, AAM-WG, ASMC, and the ASEANCOF Working Group during the first day of ASEANCOF-18.
Consensus: Rainfall
The consensus for June-July-August (JJA) 2022 outlook was achieved through an online session, which included presentations from different NMHSs, questionnaires, and discussions regarding the current climate conditions and predictions in the Southeast Asia region. In particular, ASEANCOF considered the influence of the El Niño Southern Oscillation (ENSO) and the Indian Ocean Dipole (IOD) on the climate system over Southeast Asia.
ASEANCOF-18 agreed that for the upcoming boreal (Northern Hemisphere) summer season (JJA 2022), near- to above-normal rainfall is predicted over much of the southern ASEAN region. Near- to above-normal rainfall is predicted over Brunei Darussalam and many parts of Malaysia, with above-normal rainfall predicted most elsewhere. The exceptions include parts of the western and eastern Maritime Continent, where near- to below-normal rainfall is predicted. Over much of the northern ASEAN region, a mix of below- to above-normal rainfall is predicted. Near- to below-normal rainfall is predicted over the western and southeast portion of Mainland Southeast Asia, and northwest Philippines. Near- to above-normal rainfall is predicted over portions of northeast and southern Mainland Southeast Asia, and southern Philippines. Elsewhere in the northern ASEAN region, near-normal rainfall is predicted.
Consensus maps for probabilistic outlook on rainfall and temperature for JJA 2022
Consensus: Temperature
On temperature, ASEANCOF-18 agreed that near- to above-normal temperature is predicted over the ASEAN region. The highest likelihood of above-normal temperature is over the southern Maritime Continent and Lao PDR, while near-normal temperature is predicted over northern Myanmar, northern and central Viet Nam, and parts of the western Maritime Continent. An equal chance of near- to above-normal temperature is predicted over southern Myanmar, Thailand, Cambodia, southern Viet Nam, the Philippines, Malaysia, and Brunei Darussalam.
Theme of ASEANCOF-18
The theme of ASEANCOF-18 was understanding monsoons. The NMHSs’ participants shared how they defined the monsoon in their country, including the importance of monitoring various components of the monsoon, such as onset, duration, strength, and variability. There was also a presentation from the Working Group for Asian Australian Monsoon (AAM-WG), who are working towards a regional monsoon index for Southeast Asia. Updates from this work will be presented at subsequent ASEANCOFs. Moreover, the WMO-RAP emphasized the notion of “Early Warning and early action”, where NMHSs have the essential role for the safety and wellbeing of the society particularly in ASEAN region.
Conclusion
Overall, it was a successful ASEANCOF-18. Participants expressed that they had a wonderful time and truly acquired valuable information that will be useful in NMHS’s quest to help reduce the impacts of regional scale extreme climate events and work towards objective seasonal outlooks.
Some participants also expressed their interests in the discussion on the proposed formulation of a regional monsoon index, since currently, there are projects being implemented where one of its objectives is to develop a summer monsoon index over the maritime continent both during summer and winter season.
DOST-PAGASA as the ASEANCOF-18 host, is committed to support, and shall continue to participate actively in the succeeding ASEANCOFs.
The ASEANCOF Consensus Statement for JJA 2022 can be found here.