GENERAL REVIEW OF AUGUST 2020

A total of 36 disaster events were recorded for the month of August 2020, which is the same number recorded for the previous month, and similar to the amount recorded for August of 2019. This number was more than twice as high as the August five-year average, however, the figures of affected people, internally displaced, casualties, injuries, and missing persons for August 2020 were all significantly lower than their respective five-year averages. In contrast, the number of damaged houses for August 2020 was 10 times higher than the five-year average. A little over half of the total recorded disasters for the month were flooding events, which struck regions throughout Lao PDR, the Philippines, Thailand, and Viet Nam, as well as significant numbers from Indonesia. This may be attributed to a 200mm increase in precipitation amounts for August 2020 compared to the five-year average, with especially large amounts of rainfall in Indonesia’s Sulawesi, Maluku, and Western Kalimantan, according to the Climate Hazards Group InfraRed Precipitation with Station data (CHIRPS). CHIRPS assimilates satellite imagery with in-situ data to create better approximations and more reliable precipitation distribution datasets. This data also showed precipitation deficits of at most -200 mm from the five-year average over Cambodia, Lao PDR, the coasts of Myanmar, northern Philippines and northern and central Viet Nam.

Notably, the effect of Tropical Storm (TS) SINLAKU was largely felt in the Northern and Northeastern regions of Thailand. TS SINLAKU’s impact on Thailand (during week 32) affected 111,190 persons, which was almost 50% of the total number of people affected for the region throughout the whole of August.

There were a total of 32 significant earthquakes (M≥5.0) reported in the region for August 2020, and there was heightened volcanic activity reported for Mt. Sinabung in Indonesia that exposed approximately 15,000 people to adverse impacts. Volcanic activity was also reported for Kerinci, Semeru, Ibu, and Dukono mountains in Indonesia, however the activity caused minimal damage for the surrounding areas. Meanwhile, a magnitude 6.6 earthquake in Masbate, Philippines resulted in some casualties on August 19.

SEASONAL OUTLOOK

The Southwest Monsoon conditions that have been in effect since late May are expected to continue into September 2020. However, there will be a gradual transition to inter-monsoon conditions (between monsoon seasons) during the latter part of October. This inter-monsoon period is characterised by increased shower activities, so a heightened frequency of hydrological and meteorological disasters can be expected.

The ASEAN Specialised Meteorological Centre (ASMC) predicts above-average rainfall over most parts of the southern ASEAN region, as well as the coastal regions of Cambodia, Myanmar, Thailand, and Viet Nam, serving as an early warning for those Member States. ASMC’s climate models predict La Niña conditions from September 2020, which is typically associated with wetter-than-normal conditions over the Southeast Asia region.

While above-normal rainfall is predicted in the southern ASEAN region, occasional periods of dry weather could lead to escalated hotspot activities especially in vulnerable areas in Sumatra and Kalimantan in Indonesia. This could lead to increased risk of land and forest fires and transboundary haze in the southern ASEAN region. In the northern ASEAN region, however, it is expected to be largely subdued due to the prevalence of rainy conditions.

Data Sources: ASEAN Disaster Information Network, ASEAN Specialised Meteorological Centre

Written by : Keith Paolo Landicho, Lawrence Anthony Dimailig, Aril Aditian

GENERAL REVIEW OF JULY 2020

There were 36 recorded disaster events during the month of July 2020, representing almost double the amount averaged across the previous five years. However, the number of affected people was 353,144 persons, significantly lower than the five-year average. The monthly disaster statistics also indicated lower figures in terms of internally displaced people, casualties, and injuries, which could be attributed to increased capacity in disaster management within the ASEAN Member States.

The month of July was characterised by multiple flooding events happening in Viet Nam, Myanmar, and Indonesia. The recorded flooding events were almost triple the amount of the last five years for July. Viet Nam’s Disaster Management Authority (VNDMA) reported flooding and landslides in Ha Giang and Cao Bang Provinces. On 21 July, Ha Giang City recorded 378mm of rain in 24 hours, while Dao Duc recorded 395mm and Cao Bo (both in Ha Giang Province) 401mm – while usually 180mm or more of rainfall per day is considered heavy. Meanwhile, Myanmar experienced widespread seasonal flooding due to increased rainfall in the upstream region of the Ayeyarwady river during the latter parts of the month. In Indonesia, South Sulawesi experienced multiple flooding events, with the highest impact felt in the region of North Luwu, where flash flooding took place due to heavy rainfall on 12 July. The North Luwu flooding was triggered by high-intensity rain that occurred across the two previous days, causing Masamba River, Rongkang River and Rada River to burst their banks. The North Luwu floods resulted in 38 fatalities and 14,483 displaced people, that contributed to 79% of the all ASEAN disaster casualties for the month of July.

23 significant earthquakes (M≥5.0) were recorded in the region by Indonesia’s Badan Meteorologi, Klimatologi, dan Geofisika (BMKG) and the Philippine Institute for Volcanology and Seismology (PHIVOLCS). Two volcanoes in Indonesia (Karangetang and Sinabung) are registered at Alert Level III according to Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG), and are under close monitoring. Lastly, Ibu, Semeru and Dukono mountains in Indonesia remain on Alert Level II, despite recent volcanic activity registered by the PVMBG.

SEASONAL OUTLOOK

According to seasonal outlooks from the ASEAN Specialised Meteorological Centre (ASMC), during July 2020 most of the equatorial region experienced above-average rainfall. The largest positive anomalies (wetter conditions) were recorded in the coastal equatorial regions based on satellite-derived rainfall estimates datasets. For the mainland Southeast Asia, below-average rainfall was observed over northern Viet Nam and coastal Myanmar. The prevailing Southwest Monsoon conditions are expected to continue into August and September 2020, and gradually weaken in October 2020 as the inter-monsoon period sets in. Climatologically, the Southwest Monsoon season is characterised by rainy conditions in the northern ASEAN region, and dry weather in southern ASEAN. During the August-October 2020 period, the prevailing winds in the ASEAN region are forecast to blow from the southeast or southwest.

For the August-October 2020 period there is an increased chance of above-average rainfall over much of the maritime continent and southern coastal regions of the Mekong sub-region. The equatorial Pacific Ocean are currently at neutral (neither El Niño nor La Niña) conditions, and observed indicators and models predict La Niña-like conditions to develop within the next three months. La Niña conditions are typically associated with wetter-than-normal conditions across the Southeast Asia region.

The warmer-than-average temperature is expected to continue over the ASEAN region for the next three months. However, near-normal temperatures can be expected over some parts of Borneo, northern parts of Lao PDR, and Viet Nam.

In the southern ASEAN region, while wetter-than-normal conditions are forecast over the equatorial region for the August-October period, dry conditions can still be expected over some parts of Sumatra and Kalimantan in Indonesia. This could increase the risk of land and forest fires in the region, and the occurrence of transboundary haze from such fires in the region cannot be ruled out. In the northern ASEAN region, hotspot activities are expected to remain generally subdued due to rainy weather.

Data Sources: ASEAN Disaster Information Network, ASEAN Specialised Meteorological Centre

Written by : Keith Paolo Landicho, Lawrence Anthony Dimailig, Aril Aditian

GENERAL REVIEW OF JUNE 2020

A total of 41 disaster events were recorded for the month of June 2020, which was a little lower when compared to May 2020, however, more than double the June average for the previous five years. Despite this increase, there was a significant overall decrease in the number of affected people (around 9 times less), internally displaced, injuries and missing persons recorded. However, increases to the number of damaged houses and casualties (more than threefold) were also reported. A majority of disasters recorded were flooding events (28, or almost 70%); with 20 out of those 28 occurring in Indonesia. This could be attributed to the prevalence of southwest monsoon conditions in the ASEAN region since late May, as noted by the ASEAN Specialised Meteorological Centre (ASMC). Other disasters for June 2020 included an earthquake, three landslides, four storms, and five other wind-related hazards. The recorded casualties were mainly attributed to a landslide event in the Hpakant Township of Myanmar. This landslide was reportedly triggered by heavy rain that caused the bank of the Laku creek to collapse, setting off a fatal wave of mud and torrents of water into the area used by locals to mine for jade.

From a Geophysical perspective, there was a total of 25 significant earthquakes (≥ M5.0) reported for June 2020 across the region. Volcanic activity was observed for Dukono and Semeru Volcanoes in Indonesia throughout June, however the Alert Level remained at 2. Volcanic activity was also reported for Indonesia’s Sangeang Api and Bulusan and Taal in the Philippines. The 21st of June also saw an eruption of Indonesia’s Mount Merapi, located on the border of Central Java and Yogyakarta. The eruption recorded an amplitude of 75mm and a duration of 100 seconds, and saw ash clouds reaching 8,968m above sea level, exposing 184,273 people within a 10km radius to the ash. However, no casualties were reported as a result of this eruption.

SEASONAL OUTLOOK

During July 2020, wetter conditions (above-average rainfall) for most of the equatorial region are forecast. The largest positive anomalies (wetter conditions) are expected over the coastal equatorial regions. For Mainland Southeast Asia, below-average rainfall is forecast over northern Viet Nam, northern Philippines, and coastal Myanmar. This pattern of below-average rainfall broadly follows the coastal regions between 15°N to 20°N latitudes.

The prevailing Southwest Monsoon conditions (rainy conditions in the northern ASEAN region and dry in the southern region) that have been in effect since late May are expected to continue until September 2020. These conditions are likely to bring more rains to the northern ASEAN region that could result in flooding and rain-induced landslides. However, it is expected to gradually weaken by October 2020 signalling the onset of the inter-monsoon period, that is characterised by warm weather and increased rain shower activities. By August 2020, the prevailing winds in the ASEAN region are forecast to blow from southeast to southwest. There is also an increased chance of above-average rainfall over much of the maritime continent and southern coastal regions of the Mekong sub-region.

Data Sources : ASEAN Disaster Information Network, ASEAN Specialised Meteorogical Centre

Written by : Keith Paolo Landicho, Lawrence Anthony Dimailig, Aril Aditian

GENERAL REVIEW OF MAY 2020

A total of 51 disaster events were recorded for the month of May 2020, which was an increase of 82.14% from April 2020. This also formed a three-fold increase in disaster occurrences compared to the previous five-year average, with the highest amount of recorded events for May 2020 being flooding events (56.86%). This significant increase in the number of disaster occurrences in the region was also reflected by an increase in the number of persons affected and displaced persons (both almost 2 times higher), as well as damaged houses (over 90,000 more reports). The observed increase in the impact of disaster events is largely attributed to Tropical Cyclone (TC) VONGFONG that affected the Philippines, causing a majority of the significant increase to damaged houses. According to the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA), TC VONGFONG brought more than 300 millimeters of cumulative rainfall to areas in its track, with an overall strength equivalent to Category 3 in the Saffir-Simpson Scale. Notably, casualties and number of missing people were low – with six deaths and one missing person. The number of injuries, however, significantly increased compared to the average, with a majority of such injuries due to TC VONGFONG.

Geophysically, a total of 13 significant earthquakes (M≥5.0) were reported in the region for May 2020. Volcanic activity was observed for Ibu and Sangeang Api Volcanoes in Indonesia during Week 19, as well as Dukono and Semeru Volcanoes during the last two weeks of the month. Despite increased volcanic activity, these volcanoes remained on Alert Level II, while three volcanoes (Agung, Karangetang, and Sinabung) remain on Alert Level III.

The figures are an indication of the improvement in the capacities of ASEAN Member States to monitor and report disaster events, with such improvements potentially influencing the increase in reported occurrences. There is also an indication of the effect of climate change in the region, which according to the Intergovernmental Panel on Climate Change’s (IPCC) is linked to more frequent and severe extreme weather events – floods and tropical cyclones. The outcomes also highlight the importance of early warning information and systems, as disaster impacts may have been significantly greater if not for the pre-emptive evacuation, information dissemination, and advisory issuance undertaken during TC VONGFONG in the Philippines.

SEASONAL OUTLOOK

According to the seasonal forecast of the ASEAN Specialised Meteorological Centre (ASMC) for June-July-August 2020, Southwest Monsoon conditions prevailed over the ASEAN region since the latter part of May. This is characterised by increased rain shower activities in the northern ASEAN region due to the Southwest monsoon rain band (elongated cloud patterns that bring rain). Typically drier conditions (compared to the rest of the year) can also be expected for the southern ASEAN region during the Southwest Monsoon season.

For June 2020, increased shower activities over the Mekong sub-region and subdued hotspot activities are expected. For the southern ASEAN region however, in contrast with drier Southwest Monsoon conditions, the equatorial regions should expect above-normal precipitation with isolated and generally subdued hotspot activities.

For June to August 2020, the ASMC forecasts an increased chance of above-average rainfall for most parts of the region near or on the equator. On average, above-average temperatures are also expected to persist over the ASEAN region during the next three months. In this particular season, the southern ASEAN region traditionally expects a dry season, and with it a gradual increase in hotspot activities, particularly in fire-prone areas such as Sumatra and Kalimantan, Indonesia. Extended periods of this dry weather may lead to escalation of hotspot activities, and lead to transboundary haze pollution in the region.

Data Sources: ASEAN Disaster Information Network, ASEAN Specialised Meteorological Centre

Written by : Keith Landicho and Lawrence Anthony Dimailig

GENERAL REVIEW OF APRIL 2020

The month of April 2020 evidenced a clear deviation in figures of significant disaster occurrences in comparison to the previous five-year average for April, with an 87% increase of events recorded for the month. A majority of disasters (86%) for the month of April were flooding events, with storms (11%) and landslides (3%) also registered. However, despite the increase in occurrences of significant disasters, the impact in terms of affected people was significantly lower than the five-year average with an 81% decrease. The number of people displaced by disaster events also decreased (46% less), however the impact was more severe on people’s homes with a 2 ½ times increase of damaged houses reported (17,241 in total). There were 85% less deaths as well as less injuries for April 2020 in comparison to the previous five years. 50% of all disasters for the month occurred in one week alone (week 18), which may be attributed to an increase in precipitation rates of approximately 100mm across the Indonesian islands of Sumatra and Java, compared to the previous averages during that single week.

Geophysically, for April 2020, 21 earthquakes with magnitudes greater than or equal to 5.0M were recorded by respective ASEAN Member States’ local seismic authorities. For the first half of April 2020, six volcanoes in Indonesia displayed increased activity but remained at Alert Level II according to Indonesia’s Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVBMG). Meanwhile later in the month, three volcanoes in Indonesia (Agung, Sinabung, and Karangetang) moved to at Alert Level III, with one volcano in the Philippines (Mayon) on Alert Level 2. This highlights the importance of earthquake preparedness and the immediacy of response in tectonically active countries such as Indonesia and the Philippines based on their location along the Pacific Ring of Fire.

SEASONAL OUTLOOK

During the May to July 2020 period, rainfall over the northern ASEAN region is forecast at below-average rates. Similar forecasts for rainfall conditions are predicted for most parts of western mainland Southeast Asia (Myanmar, northern Thailand and northern Laos), however most parts of the southern ASEAN region can expect above-average rainfall. Overall, the entire ASEAN region can expect above-average temperatures.

In the Mekong sub-region, the start of the Southwest Monsoon period should improve haze conditions and gradually subdue hotspot and fire activities. In the southern ASEAN region, hotspot activities are expected to remain generally subdued for May 2020. However, a gradual increase in hotspot activities, particularly in the fire-prone areas of Sumatra and Kalimantan, can be expected from June with the onset of the traditional dry season in the southern ASEAN region.

Data Sources: ASEAN Disaster Information Network, ASEAN Specialised Meteorological Centre

Written by : Keith Landicho and Lawrence Anthony Dimailig

GENERAL REVIEW OF MARCH 2020

The month of March ended the first quarter of 2020, with a small reduction (11%) of disaster occurrences when compared to the five-year average for the month, with a majority of the recorded disasters formed by flooding events. The number of people affected remained similar to the March average, with a substantial amount due to the storms that occurred in Viet Nam during the first and third weeks of the month, as well as from multiple localised flood events and landslides in Indonesia. While impact numbers remained steady, the was a significant decrease in numbers of displaced persons – which was measured at a 63% decrease compared to the five-year average. On the other hand, damaged house statistics rose to over 10 times the five-year average. This overwhelming increase can be attributed again to the storms and flooding in Indonesia and Viet Nam. Human casualties also measured only 27.27% of the five-year average, with a number of deaths caused by storms in the northeastern provinces of Thailand, where lightning strikes took the lives of three individuals. Additionally, week-long rains, thunderstorms and tornadoes in in the northern provinces of Viet Nam also caused a number of fatalities. Substantial decreases to missing and injured persons were also recorded for the month. According to the Climate Forecast System (CFS) of the National Oceanic and Atmospheric Administration (NOAA), average precipitation values for the month of March 2020 showed a 50 to 100 millimetre increase across northeastern parts of Thailand, northern parts of Viet Nam, and the islands of Java, Sulawesi and Kalimantan in Indonesia. This increase potentially stands as a key cause of the significant increases to affected people and damaged houses. Such figures also highlight the perennial problem flooding in Indonesia, as well as the importance of the availability and accessibility of early warning information. The significant amounts of damaged houses also highlights the importance of climate change-adaptive and resilient structures.

Related to geophysical activity, 26 earthquakes of magnitudes greater than or equal to 5.0M were recorded for the month of March 2020. Contrary to the first two months of the year that saw no significant earthquake events reported, the month of March saw one earthquake that resulted in a minor disaster event in Indonesia. The earthquake registered a magnitude of 4.9M, but was enough to rock the western parts of Java causing 3 injuries and damage to 202 houses. No tsunami warning was issued by BMKG as the epicenter was located underneath land, with the earthquake recorded on a strike-slip fault where two tectonic plates moved in parallel but opposite directions to one another.

SEASONAL OUTLOOK

According to the ASEAN Specialised Meteorological Centre (ASMC), inter-monsoon conditions (that typically span from April until May) are expected over the region, which is described as the transition between the Northeast and Southwest Monsoons. This inter-monsoon condition is expected to gradually transition to the Southwest Monsoon around the end of May or early June. The inter-monsoon conditions are characterised by increased occurrence of scattered rain showers in the region, higher probabilities of thunderstorms, and intensification of lightning activity. Despite the expected inter-monsoon conditions for the period of April to June 2020, the ASMC expects below-normal rainfall in ASEAN regionals areas north of the equator. This should bring about warmer-than-normal conditions for Brunei Darussalam, Cambodia, Malaysia, Myanmar, the Philippines, Singapore, and the northern Sumatra and Kalimantan islands of Indonesia. While the amount of forecasted rainfall may not be alarming, the region should still be cautious for thunderstorms, lightning activity, and increased occurrence of scattered rain showers that are characteristic of inter-monsoon conditions. Increased exposure to, and occurrence of, localised rainfall may still cause flooding and rain-induced landslides.

With warmer and drier conditions predicted in the Mekong sub-region, hotspot activities are expected to remain elevated and the prevailing haze is likely to persist despite the inter-monsoon conditions. Hotspot activities are expected to remain subdued with localised hotspot activities and haze emerging occasionally. Towards June, prevailing winds change in direction from northeast to southwest, which is known as the Southwest Monsoon season, itself characterised by the direction of winds from sea to land. These winds are known to carry more moisture, coming from the sea, and causing more rain.

Data Sources: ASEAN Disaster Information Network, ASEAN Specialised Meteorological Centre

Written by : Keith Landicho and Lawrence Anthony Dimailig

GENERAL REVIEW OF FEBRUARY 2020

The 21 disaster occurrences for the month of February 2020 was similar to the five-year average for the month (20). A majority of the recorded disasters were flood events in different regions across Indonesia, most of which occurred towards the end of February. A single flooding event in the Johor State in Malaysia was also recorded at the end of the month. Adding to this, four landslides were recorded to have occurred in Indonesia for this month, including in Bandung Regency in the second week, and three during the last week of the month in Tasikmalaya district, Bandongan district, and Magelang Regency. Based on this, significant differences related to five-year disaster impact averages were observed. This included a 95% increase in the number of affected people, more than double the amount of internally displaced people, and four times the number of damaged houses. There was, however, a 36% decrease in the number of casualties alongside no reports of injured and missing people.

According to reports by the Indonesian Meteorology, Climatology, and Geophysics Agency (BMKG), the presence of two tropical cyclones (TC) – TC Esther in Gulf of Carpentaria and TC Ferdinand in the Indian Ocean – influenced the heavy rainfall that caused flooding events. Accordingly, based on the Climate Forecast System (CFS) of the National Oceanic and Atmospheric Administration (NOAA), average precipitation in millimeters peaked twice for the month of February on the island of Java. The first peak occurred in the second week with the second at the end of the month, supporting the cause of the flooding that took place at the end of February. Additionally, based on the CFS (which assimilates ground, air, aircraft, and satellite observations) findings, maximum precipitation differences for the month of February 2020 compared to five-year average rainfall values reached an approximate increase of 100 millimetres.

Based on disaster comparisons, the number of flooding events are 13.33% higher than the five-year average. Despite this relatively low increase in numbers, there was a significant increase in figures related to impact of the disasters. The increase in the extent and severity of the impacts may be an indication of a changing climate. However, the efforts of Indonesia’s National Disaster Management Authority (BNPB), and measures implemented to curtail the impacts of disasters resulted in the decrease to numbers of casualties. Additionally, the dramatic increase in the number of damaged houses could further support the call for more climate change-adaptive and resilient structures in disaster-stricken regions.

SEASONAL OUTLOOK

According to the ASEAN Specialised Meteorological Centre (ASMC), enhanced chances of below-normal rainfall or drier conditions are expected over northern parts of Sumatra, Kalimantan, and Sulawesi, Brunei Darussalam, Cambodia, Singapore, Malaysia, and the southern regions of Myanmar, Thailand, Viet Nam, and of the Philippines for the March-May 2020 season. For regions south of the equator, the ASMC predicts above-normal rainfall or wetter conditions. Temperature-wise, most parts of the ASEAN region are expected to continue experiencing warmer conditions for the March-May 2020 period.

Haze outlook for the ASEAN region during March-May 2020 is expected to show increased hotspot activities due to drier conditions. A deterioration of haze situation is displayed for the Northern Mekong sub-region, according to the ASMC. The onset of increased rainfall is foreseen to subdue hotspot activities and improve the haze situation in the region. Lastly, the haze situation in the southern ASEAN region is expected to remain subdued, but localised hotspots may emerge during the occasional dry weather.

Continent as predicted by the models.

Data Sources: ASEAN Disaster Information Network, ASEAN Specialised Meteorological Centre

Written by : Keith Landicho and Lawrence Anthony Dimailig

GENERAL REVIEW OF JANUARY 2020

A significant change in the number of disaster occurrences was observed for the month of January 2020, with a 56% decrease of all disasters in comparison to the previous five-year average, and a majority of registered disasters were flood events. All but one of the recorded disasters took place in Indonesia. There were, however, significant increases compared to five-year averages of affected people (13% increase), internally displaced people (86%), and damaged houses (8%), due primarily to high monsoon activity in the region, with winds exhibiting convergence patterns (leading to formation of clouds and eventually precipitation) according to the Indonesian Meteorology, Climatology, and Geophysics Agency (BMKG). Overall, the number of occurrences decreased, but the disasters affected more people compared to the previous five-year averages.

There was also a significant increase in the number of casualties for the month of January, up 63% compared to the five-year average, with the number of injuries also increasing by 32%, despite the life-saving mechanisms of the ASEAN Member States being effectively put into place. Such increased disaster severity may be an indication of the effects of a changing climate. In terms of geophysical hazards, the phreatic eruption of the Taal Volcano in the Philippines on January 12 spewed ash across Metro Manila, and the Northern, Central, and Southern Luzon regions, causing widespread cancellations of classes, work, and flights, and significant losses for the agricultural sector (US$63 million). The Philippine Institute of Volcanology and Seismology (PHIVOLCS) issued an Alert Level 4 (out of five levels), or hazardous eruption possible within hours to days, due to the volcanic activity. On 26 January, decreased volcanic activities prompted PHIVOLCS to downgrade that alert level. Taal Volcano’s eruption contributed significantly to the number of displaced people in this month’s figures, with an estimated 459,300 people living within the volcano’s 14-kilometer danger zone.

SEASONAL OUTLOOK

The ASEAN Specialised Meteorological Centre (ASMC) expects drier conditions for the month of February over Sumatra, Peninsular Malaysia and northern parts of Borneo and the Philippines. These conditions are expected to last until the end of March and extend to some parts of Thailand. However, wetter conditions are expected with increasing chances over the southeastern part of the maritime continent in the following months, which are expected to ease in the last week of March.

For temperature conditions, on one hand, the ASMC expects warmer conditions over much of the maritime continent and shall progressively affect parts of Mainland Southeast Asia in the last week of March. On the other hand, colder conditions are expected to occur and last until the third week of February over northeastern parts of the northern ASEAN region.

The Madden-Julian Oscillation (MJO), characterised by an eastward spread of large regions of enhanced and suppressed tropical rainfall, is expected to be in Phase 7 of 8 towards the end of January 2020. This means the enhanced rainfall will continue to move eastward into the western Pacific and eventually dissipate in the central Pacific. There are signs of a weak MJO emerging in the Maritime Continent in mid-February, but is forecasted to weaken. This weak MJO is also forecasted to reemerge over the Indian Ocean towards the end of March. This development may contribute to wetter conditions in the Southern Maritime Continent as predicted by the models.

Data Sources: ASEAN Disaster Information Network, ASEAN Specialised Meteorological Centre

Written by : Keith Landicho and Lawrence Anthony Dimailig

GENERAL REVIEW OF DECEMBER 2019

December 2019 significantly shifted from the previous five-year average December disaster statistics, recording a higher number of occurrences, impact to population, and damage to houses, albeit with lower casualty rates. The number of disaster occurrences experienced a 61% increase compared to the previous five December periods, with flood events contributing the largest share. A majority of flooding events took place in Indonesia towards the end of the month when the country was experiencing strong impacts from the Madden-Julian Oscillation. Meanwhile, considerable deviations in the number of affected (168% increase from the five-year average) and displaced (187% increase from the five-year average) people and damaged houses (716% increase from the five-year average) were driven by Typhoons KAMMURI (equivalent to Category 4 hurricane at peak strength) and PHANFONE (equivalent to Category 2 hurricane at peak strength) hitting the Philippines within a three week timeframe. Combined, both typhoons are estimated to account for 79% of affected people figures, 55% of displaced people, and 97% of damaged houses reported in the last month of 2019.

On the other hand, there were notable decreases in casualty figures compared with the five-year average – with 60% decrease in dead, 30% decrease in injured, and 84% decrease in missing people. This suggests that in spite of extensive disaster impact this month, life-saving mechanisms in ASEAN Member States were effectively implemented. In terms of geophysical hazards, there were 24 recorded earthquakes of magnitude 5.0 and above, one of which was a magnitude 6.9 earthquake in the Southern Philippines, affecting hundreds of thousands of people, and contributing to more than a quarter of the displacement figures.

SEASONAL OUTLOOK

The ASEAN Specialised Meteorological Centre (ASMC) expects the Northeast Monsoon to prevail over the region until late March to early April, before transitioning towards the inter-monsoon phase. Traditionally, the Northeast Monsoon results in a dry season in the northern ASEAN region, while the rainy season persists in the southern parts of the region. In terms of main weather and climate drivers in the region, both El Niño Southern Oscillation and Indian Ocean Dipole systems are expected to be in neutral phase for the next few months, and there are signs of weakening Madden-Julian Oscillation over the coming weeks.

Above-average temperatures over most parts of the ASEAN region for the next few months is predicted by global weather and climate prediction models, with moderate to high probability of this happening. Alongside this, below-average rainfall is predicted over Myanmar and the Philippines, while there is a higher chance of above-normal rainfall around the Java Sea area and the eastern archipelago of Indonesia, which may result in flooding.

Data Sources: ASEAN Disaster Information Network, ASEAN Specialised Meteorological Centre

Written by : Lawrence Anthony Dimailig and Shahasrakiranna

GENERAL REVIEW OF NOVEMBER 2019

The number of disaster occurrences during November 2019 was only slightly above 50% of the previous five-year average. November is the usually the month that sees the beginning of the Northeast Monsoon, bringing more rains, especially to the southern part of the ASEAN region. However, this year the positive Indian Ocean Dipole (IOD) has affected several parts of the region resulting in less rain. This is reflected by significant decreases in flooding events for the period – and the year in general – particularly in Indonesia.

The number of affected and displaced persons during the month of November also only reached about 15% and 26% compared to the previous five-year November average, while the number of damaged houses was also less than 20%. Of note is also that during the last five years, two major events (namely as Typhoon Hagupit in 2014 and Typhoon Damrey in 2017) affected more than 8 million people, and displaced more than 500,000. Most of the disasters that occurred in November 2019 were registered as minor to moderate, including Typhoon Nakri, which affected the Philippines and Viet Nam in early November, and several earthquakes in Indonesia, the Philippines, and the border of Lao PDR and Thailand. The overall decreased impact of disasters could be related to both the amount and scale of actual disasters, and also the national capacity of ASEAN Member States to respond internally.

SEASONAL OUTLOOK

According to the ASEAN Specialised Meteorological Centre (ASMC), the transition to Northeast Monsoon season began in mid-November. During this period, the northern ASEAN region typically experiences dry conditions, while the southern ASEAN region experiences rainy weather. With a surge of cool air from the northern Asian landmass expected to blow toward the Equatorial Southeast Asia region, the Mekong sub-region, South China Sea, and the surrounding areas (including Peninsular Malaysia and parts of Sumatra) can expect cooler temperatures during the outlook period. In contrast, warm conditions are forecast over the Indonesian archipelago around the Java Sea region. There is a high likelihood of above-average temperatures over most parts of the region during the December 2019 until February 2020.

In terms of rainfall outlook, there are no clear trends for the December 2019 to February 2020 season, but there is an increased chance of below-average rainfall over most parts of the region south of the equator who may experience drier-than-normal conditions in December 2019. Wetter conditions are expected over the western Maritime Continent, including central Sumatra, Peninsular Malaysia, Singapore and parts of western Borneo. Likewise, in December 2019, the Mekong sub-region and the eastern Indonesian archipelago can expect a gradual increase in hotspot activities as the dry season sets in. Based on past trends, an escalation of hotspot activities can be expected in late January and February, particularly over Thailand and Cambodia. Hotspot activities in the southern ASEAN region are expected to remain generally subdued, however isolated hotspots may emerge in Sumatra, Kalimantan and Malaysia during periods of dry weather, especially in February. Generally, above-average temperatures are likely over most parts of Southeast Asia from December 2019 to February 2020. Meanwhile, the El Niño Southern Oscillation (ENSO) monitoring system remains in “Neutral” state, and model outlooks from international centres are predicting sea surface temperature anomalies to remain at this status until early 2020.

Data Sources: ASEAN Disaster Information Network, ASEAN Specialised Meteorological Centre

Written by : Lawrence Anthony Dimailig and Shahasrakiranna