GENERAL REVIEW OF FEBRUARY 2021

February 2021 was characterised by a significantly higher number of disaster occurrences in comparison to the average from February during the previous five years – with a six-fold increase overall. In-line with this increase, statistics show significantly higher comparative numbers of affected people (almost 6 times the February five-year average), internally displaced (7 ½ times), damaged houses (36 times), casualties (2 ½ times), and missing persons (7 times). A majority of recorded disasters in February occurred in Indonesia, over 70% of which were floods. These increases can be largely attributed to the Northeast Monsoon conditions that brought wetter conditions to Indonesia (Java Island and regions around it), causing flooding, rain-induced landslides and heavy winds. The effects of a frontal system’s tail end were also evident in eastern parts of the Philippines, which was also subject to Tropical Storm DUJUAN that affected 272,500 people living in the area. La Niña conditions are still present in the tropical Pacific Ocean, and continue to be associated with wetter conditions for Southeast Asia.

A total of 32 significant earthquakes (M≥5.0) were reported in the region during February 2021, although they caused limited damages to populations and infrastructure. Volcanic activity was reported for numerous Alert Level III volcanoes – including Mount Merapi, Sinabung, Semeru, and Karangetang in Indonesia – all of which remain under close monitoring. Recent volcanic activity was also reported for Ibu, Dukono, and Raung mountains in Indonesia, and Taal in the Philippines, but there were no significant related damages.

SEASONAL OUTLOOK

According to the ASEAN Specialised Meteorological Centre (ASMC), the prevailing Northeast Monsoon conditions are expected to continue into March 2021. During this period, the prevailing northeasterly or easterly winds over the northern ASEAN region could strengthen at times due to the influence of high pressure systems moving eastwards over continental Asia. In addition to the traditional dry season over the northern ASEAN region, areas in the equatorial parts of the southern ASEAN region could occasionally experience dry and windy conditions during March, as they are in the dry phase of the Northeast Monsoon. Inter-monsoon conditions are expected to develop in April and continue into May 2021. The prevailing winds across the ASEAN region are expected to be light and variable, and an increase in shower activities is forecast for the ASEAN region during this period.

For the March to May 2021 period, models predict above-normal rainfall over much of the ASEAN region north of the equator. La Niña conditions are present over the tropical Pacific Ocean, with climate models predicting La Niña conditions to weaken over the boreal spring (March – June). La Niña conditions are typically associated with wetter-than-normal conditions over the Southeast Asia region. While below-average rainfall is expected for much of Indonesia’s Sumatra, Borneo and Sulawesi islands for March – May, these areas tend to be less influenced by La Niña conditions at this time of year. Warmer-than-average temperatures are expected over the equatorial region for the period, with much of mainland Southeast Asia, except Myanmar, experiencing below to near-average temperatures.

Despite the slight chance of above-normal rainfall outlook over the Mekong sub-region in March-May 2021, dry conditions are expected to persist, as it is still the traditional dry season for the Mekong sub-region. During this period, the hotspot situation and risk of transboundary haze occurrence in the sub-region are likely to remain elevated. The gradual return of wet weather conditions from April 2021 onwards is expected to bring some respite to elevated hotspot and haze occurrences over parts of the sub-region. In the southern ASEAN region, hotspot activities should generally subdued during this outlook period. However, during periods of drier weather, there may be brief occurrences of isolated hotspots with localised smoke plumes, in particular over parts of the equatorial region where below-normal rainfall is forecast.

The qualitative outlook is assessed for the region in general and based on the latest runs from models provided by the SEA RCC-Network LRF node. For specific updates on the national scale, the relevant ASEAN Member States’ National Meteorological and Hydrological Services should be consulted.

Sources : ASEAN Disaster Information Network (ADINet), ASEAN Specialised Meteorological Centre (ASMC), ASEAN Disaster Monitoring and Response System (DMRS), Badan Nasional Penanggulangan Bencana (BNPB), Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG), Badan Meteorologi, Klimatologi dan Geofisika (BMKG), National Disaster Risk Reduction and Management Council (NDRRMC), Philippine Institute for Volcanology and Seismology (PHIVOLCS), National Disaster Management Agency – Malaysia (NADMA), Department of Disaster Prevention and Mitigation – Thailand (DDPM), Viet Nam Disaster Management Authority (VNDMA)

Written by : Keith Paolo Landicho, Sadhu Zukhruf Janottama,  Lawrence Anthony Dimailig