Category Archives: Haze Review for Year 2020

January 26, 2021

Review of Regional Haze Situation for December 2020

1.1 Northeast Monsoon conditions prevailed over the ASEAN region in December 2020. In the northern ASEAN region, the prevailing winds blew mainly from the northeast or east during this month, with moderate to strong northeasterly winds over the southeastern Mekong sub-region on several days. Dry conditions developed over the Mekong sub-region, except over coastal areas of Viet Nam where isolated showers were observed on a few days. In the southern ASEAN region, isolated to scattered showers fell over most areas with the prevailing winds blowing mainly from the west or northeast. Rainfall activity was highest in southern Thailand, northern Peninsular Malaysia, Java and eastern coastal areas of the Philippines.

Figure 1: Average Daily Rainfall and Mean Wind for December 2020. (Source: JAXA GsMaP and GFS respectively)

1.2 The hotspot counts in the ASEAN region for December 2020 remained relatively low when compared to the same review period in previous years (Figure 2 and Figure 3).

Figure 2: Hotspot counts for the northern ASEAN region for the month of December between 2016 and 2020. [Note: The hotspot counts from 2019 onwards are based on the NOAA-20 satellite, while those from 2016-2018 are based on the Suomi-NPP satellite.]

Figure 3: Hotspot counts for the southern ASEAN region for the month of December between 2016 and 2020. [Note: The hotspot counts from 2019 onwards are based on the NOAA-20 satellite, while those from 2016-2018 are based on the Suomi-NPP satellite.]

1.3 Isolated to scattered hotspots were detected in many parts of the Mekong sub-region in December 2020. In particular, localised smoke plumes were observed to emanate from some of the isolated hotspots in Cambodia, Myanmar and Thailand. In the southern ASEAN region, the hotspot situation was subdued by rainy conditions.

Figure 4: Distribution of hotspots detected based on NOAA-20 satellite surveillance for December 2020.

Figure 5: Maximum fire intensity based on NOAA-20 satellite surveillance for December 2020.

December 21, 2020

Review of Regional Haze Situation for November 2020

1.1 Intermonsoon conditions over the ASEAN region gradually made way for the Northeast Monsoon in November 2020. The prevailing winds blew from the northeast or east over the northern ASEAN region and were light and variable over the southern ASEAN region. In the northern ASEAN region, dry weather prevailed over most of the Mekong sub-region except for the coastal regions of southern Viet Nam where higher rainfall was observed partly due to Super Typhoon Goni. The average daily rainfall (Figure 1) was highest in the Philippines under the influence of Tropical Storm Etau, Typhoon Vamco and Super Typhoon Goni. Wet weather prevailed over most parts of the southern ASEAN region as the monsoon band moved south towards the equator.

Figure 1: Average Daily Rainfall and Mean Wind for November 2020. (Source: JAXA GsMaP and GFS respectively)

1.2 Due to drier conditions over parts of Kalimantan, Myanmar and Thailand, hotspot counts in these regions were slightly elevated compared to the same review period in 2016 – 2018 but lower than those in 2019. Elsewhere over the ASEAN region, the hotspot counts were comparable to those in previous years’ review periods (Figures 2 and 3).

Figure 2: Hotspot counts for the southern ASEAN region for the month of November between 2016 and 2020. [Note: The hotspot counts from 2019 onwards are based on the NOAA-20 satellite, while those from 2016-2018 are based on the Suomi-NPP satellite.]

Figure 3: Hotspot counts for the northern ASEAN region for the month of November between 2016 and 2020. [Note: The hotspot counts from 2019 onwards are based on the NOAA-20 satellite, while those from 2016-2018 are based on the Suomi-NPP satellite.]

1.3 In November 2020, Isolated hotspots were detected in many parts of the ASEAN region, particularly in Kalimantan, the Lesser Sunda Islands, Sulawesi, and the Mekong sub-region (Figure 4). On a few days in November 2020, localised smoke plumes were observed to emanate from some of the hotspots in Kalimantan, Sulawesi, and the Myanmar. Otherwise, no significant smoke haze was observed.

Figure 4: Distribution of hotspots detected based on NOAA-20 satellite surveillance for November 2020.

Figure 5: Maximum fire intensity based on NOAA-20 satellite surveillance for November 2020.

November 13, 2020

Review of Regional Haze Situation for October 2020

1.1 Southwest Monsoon conditions persisted over the ASEAN region in October 2020. The prevailing winds blew mainly from the southeast or southwest except over the Mekong sub-region where winds were mostly variable under the influence of several low-pressure systems. In the northern ASEAN region, rainy weather persisted throughout most of the month. The average daily rainfall (Figure 1) was highest in Luzon Island of the Philippines and central regions of Viet Nam under the influence of the tropical storms Lingfa, Nangka and Saudel, Typhoon Malave and Super Typhoon Goni. In the southern ASEAN region, despite this time of the year typically being the dry season, shower activities were still observed over many areas on most days. There was little variation in average daily rainfall across the southern ASEAN region except for generally dry conditions observed mainly over the regions surrounding the Java Sea and Flores Sea.

Figure 1: Average Daily Rainfall and Mean Wind for October 2020. (Source: JAXA GsMaP and GFS respectively)

1.2 The hotspot counts in the ASEAN region for October 2020 remained relatively low when compared to the same review period in previous years due to wet weather (Figure 2 and Figure 3).

Figure 2: Hotspot counts for the southern ASEAN region for the month of October between 2016 and 2020. [Note: The hotspot counts from 2019 onwards are based on the NOAA-20 satellite, while those from 2016-2018 are based on the Suomi-NPP satellite.]

Figure 3: Hotspot counts for the northern ASEAN region for the month of October between 2016 and 2020. [Note: The hotspot counts from 2019 onwards are based on the NOAA-20 satellite, while those from 2016-2018 are based on the Suomi-NPP satellite.]

1.3 Isolated hotspots were detected in many parts of the ASEAN region in October 2020, particularly in Kalimantan, the Lesser Sunda Islands, and Sulawesi (Figure 4) during brief periods of drier weather. On a few days in October 2020, localised smoke plumes were observed to emanate from some of the hotspots in Kalimantan. Otherwise, no significant smoke haze was observed.

Figure 4: Distribution of hotspots detected based on NOAA-20 satellite surveillance for October 2020.

Figure 5: Maximum fire intensity based on NOAA-20 satellite surveillance for October 2020.

October 20, 2020

Review of Regional Haze Situation for September 2020

1.1 Southwest Monsoon conditions persisted over the ASEAN region in September 2020 and the prevailing winds blew mainly from the southeast or southwest. In the northern ASEAN region, rainy weather persisted throughout most of the month, particularly during the third week when Tropical Storm Noul made landfall over the Mekong sub-region and brought widespread showers. Average daily rainfall (Figure 1) was highest in coastal areas of Vietnam, Cambodia and Myanmar. In the southern ASEAN region, shower activities were frequently observed over many areas despite this period of the year being its traditional dry season. Average daily rainfall was highest in northwestern Borneo, northern Sumatra and West Papua while generally dry conditions were observed mainly over the Java Sea region.

Figure 1: Average Daily Rainfall and Mean Wind for September 2020. (Source: JAXA GsMaP and GFS respectively)

1. 1.2 The hotspot counts in the ASEAN region for September 2020 remained relatively low when compared to the same review period in previous years due to wet weather (Figure 2 and Figure 3).

Figure 2: Hotspot counts for the southern ASEAN region for September 2016 – 2020. [Note: The hotspot counts from 2019 are based on the NOAA-20 satellite, while those from 2016-2018 are based on the Suomi-NPP satellite.]

Figure 3: Hotspot counts for the northern ASEAN region for September 2016 – 2020. [Note: The hotspot counts from 2019 are based on the NOAA-20 satellite, while those from 2016-2018 are based on the Suomi-NPP satellite.]

1.3 Isolated hotspots were detected in many parts of the ASEAN region in September 2020. In particular, persistent clusters of hotspots were detected in Viet Nam, the Lesser Sunda Islands, and some parts of Kalimantan (Figure 4). Localized smoke haze was also observed to emanate from some of the intense hotspots in Kalimantan during the second half of the month.

Figure 4: Distribution of hotspots detected based on NOAA-20 satellite surveillance for September 2020.

Figure 5: Maximum fire intensity based on NOAA-20 satellite surveillance for September 2020.

September 17, 2020

Review of Regional Haze Situation for August 2020

1.1 In August 2020, Southwest Monsoon conditions prevailed over the ASEAN region and the prevailing winds blew from the southeast or southwest. The location of the monsoon rain band north of the Equator, combined with the impact of Tropical Storms Sinlaku/Mekkhala and Typhoon Maysak, contributed to the rainy weather over most of the northern ASEAN region (Figure 1). In the southern ASEAN region, the weather was mostly dry in the first half of the month followed by an increase in shower activities over the equatorial region in the latter half of the month.

Figure 1: Average Daily Rainfall and Mean Wind for August 2020. (Source: JAXA GsMaP)

1.2 The hotspot counts were observed to be relatively low when compared to the same review period in previous years for most parts of the ASEAN region due to the wetter weather (Figure 2 and Figure 3).

Figure 2: Hotspot counts for the southern ASEAN region for August 2016 – 2020. [Note: The hotspot count from 2019 is based on the NOAA-20 satellite, and based on the Suomi-NPP satellite for the period from 2016-2018.]

Figure 3: Hotspot count for the northern ASEAN region for August 2016 – 2020. [Note: The hotspot count from 2019 is based on the NOAA-20 satellite, and based on the Suomi-NPP satellite for the period from 2016-2018.]

1.3 In August 2020, isolated hotspots were detected mostly in Kalimantan and Sumatra, as well as in some parts of Java, Nusa Tenggara and Viet Nam (Figure 4). While most of the hotspots detected in the ASEAN region were short-lived, a cluster of hotspots with high fire intensity (Figure 5) was observed to persist for more than a week (Figure 4) in West Kalimantan. Isolated smoke plumes were observed to emanate from some of these hotspots and affected the western parts of Sarawak on 8 August 2020.

Figure 4: Distribution of hotspots detected based on NOAA-20 satellite surveillance for Jul 2020.

Figure 5: Maximum fire intensity based on NOAA-20 satellite surveillance in Jul 2020.

August 13, 2020

Review of Regional Haze Situation for July 2020

1.1 In July 2020, Southwest Monsoon conditions prevailed over the ASEAN region, with low-level winds blowing from the southeast or southwest. This period is typically associated with the traditional dry season over the southern ASEAN region and traditional rainy season over the northern ASEAN region. However, during most parts of the review period, the monsoon rain band remained over the equatorial Southeast Asia region and brought wet weather on many days to the equatorial southern ASEAN region. Around the last week of July 2020, the monsoon rain band shifted north, and this brought brief periods of dry weather over the southern ASEAN region, including Peninsular Malaysia, Sumatra and Kalimantan. This indicated the start of the traditional dry season for the southern ASEAN region. In the northern ASEAN region, rainy weather continued to prevail throughout the review period.

Figure 1: Average Daily Rainfall for Jul 2020. (Source: JAXA GsMaP)

1.2 The rainy weather in July 2020 contributed to the relatively low number of hotspots detected in the northern and southern ASEAN region, compared to the same period in previous years.

Figure 2: Hotspot count for the northern ASEAN region for Jul 2013 – 2020. [Note: Hotspot count from year 2019 onward is based on the NOAA-20 satellite, and for the period from year 2013-2018 is based on the Suomi-NPP satellite.]

Figure 3: Hotspot count for the southern ASEAN region for Jul 2013 – 2020. [Note: Hotspot count from year 2019 onward is based on the NOAA-20 satellite, and for the period from year 2013-2018 is based on the Suomi-NPP satellite.]

1.3 In July 2020, isolated hotspots were detected in parts of Viet Nam, Malaysia, Sumatra and Kalimantan. Occasionally, a few clusters of hotspots with localised smoke plumes were observed in Sumatra and Kalimantan, but the hotspots were short-lived and no significant smoke haze were observed.

Figure 4: Distribution of hotspots detected based on NOAA-20 satellite surveillance for Jul 2020.

1.4 The fire intensity of hotspots detected in the ASEAN region in July 2020 was low. No significant smoke haze was observed from satellite surveillance and ground reports.

Figure 5: Maximum fire intensity based on NOAA-20 satellite surveillance in Jul 2020.

July 17, 2020

Review of Regional Haze Situation for June 2020

1.1 Southwest Monsoon conditions prevailed over the ASEAN region in June 2020. The prevailing winds in the region generally blew from the southeast or southwest. While the traditional dry season of the southern ASEAN region typically starts in June, during the review period, there have been persistent and widepread showers over the southern ASEAN region brought about by the close proximity of the monsoon rain band. The prevailing wet conditions over the Mekong sub-region during this period is typical of the traditional rainy season associated with the Southwest Monsoon of the northern ASEAN region.

Figure 1: Average Daily Rainfall for Jun 2020. (Source: JAXA GsMaP)

1.2 2. In Jun 2020, the number of hotspots detected in both the northern and southern ASEAN region remained generally subdued due to rainy weather. In particular, the total number of hotspots detected in the southern ASEAN region for Jun 2020 was the lowest ever recorded since year 2013.

Figure 2: Hotspot count for the northern ASEAN region for Jun 2013 – 2020. [Note: Hotspot count from year 2019 onward is based on the NOAA-20 satellite, and for the period from year 2013-2018 is based on the Suomi-NPP satellite.]

Figure 3: Hotspot count for the southern ASEAN region for Jun 2013 – 2020. [Note: Hotspot count from year 2019 onward is based on the NOAA-20 satellite, and for the period from year 2013-2018 is based on the Suomi-NPP satellite.]

1.3 While hotspot activities in the region remained subdued, isoted hotspots were still detected in parts of Viet Nam and Sumatra on some days. Localised smoke plumes were observed to emanate from some hotspots in Riau, Sumatra and Central Kalimantan. These hotspots however were short-lived and did not contribute to any significant smoke haze.

Figure 4: Distribution of hotspots detected based on NOAA-20 satellite surveillance for Jun 2020.

1.4 In June 2020, the fire intensity of hotspots detected across the region was low. There was no significant smoke haze observed based on satellite imageries and ground reports.

Figure 5: Maximum fire intensity based on NOAA-20 satellite surveillance in Jun 2020.

June 4, 2020

Review of Regional Haze Situation for May 2020

1.1 The inter-monsoon conditions that prevailed over the ASEAN region in May 2020 transitioned to Southwest Monsoon conditions in late-May 2020. The presence of the monsoon rain band further north of the Equator brought an increase in shower activities over the Mekong sub-region in the latter half of the month. In the southern ASEAN region, scattered showers fell over most parts of the region. During the review period, the prevailing winds over the ASEAN region were light and variable in direction but gradually shifted to blow from the southeast or southwest with the start of the Southwest Monsoon season.

Figure 1: Average Daily Rainfall for May 2020. (Source: JAXA GsMaP)

1.2 In early May 2020, most of the hotspot activities were detected in Lao PDR, Myanmar and Viet Nam. An increase in shower activities over the northern ASEAN region during the month contributed to a gradual reduction of hotspot activities in the Mekong sub-region. In the southern ASEAN region, the hotspot activities continued to remain subdued due to wet weather over many parts of the region.

Figure 2: Hotspot count for the northern ASEAN region for May 2013 – 2020. [Note: Hotspot count from year 2019 onward is based on the NOAA-20 satellite, and for the period from year 2013-2018 is based on the Suomi-NPP satellite.]

Figure 3: Hotspot count for the southern ASEAN region for May 2013 – 2020. [Note: Hotspot count from year 2019 onward is based on the NOAA-20 satellite, and for the period from year 2013-2018 is based on the Suomi-NPP satellite.]

1.3 In May 2020, clusters of hotspots were detected mostly in the northern part of Lao PDR. These hotspots persisted for about one week. Isolated hotspots were also detected in Cambodia and Viet Nam on many days. In the southern ASEAN region, short-lived isolated hotspots were detected on some days.

Figure 4: Distribution of hotspots detected based on NOAA-20 satellite surveillance for May 2020.

1.4 In May 2020, hotspot activities were more intense in the northern parts of Myanmar and Lao PDR. Some of these hotspot activities contributed to the occurrence of smoke haze in the sub-region.

Figure 5: Maximum fire intensity based on NOAA-20 satellite surveillance in May 2020.

1.5 The increase in shower activities brought a further improvement to the haze situation in the Mekong sub-region in the first half of May 2020. During periods of drier weather in early May 2020, moderate smoke haze was observed mainly in the northern parts of Lao PDR. Localised smoke plumes were also observed to emanate from some of the hotspots in the Mekong sub-region on some days. In the southern ASEAN region, while there were localised hotspot activities, no significant smoke haze was observed.

Figure 6: Number of days with moderate to dense smoke haze observed over an area based on satellite imageries, ground observations and air quality reports in May 2020.

May 5, 2020

Review of Regional Haze Situation for April 2020

1.1 Northeast Monsoon conditions prevailed over most parts of the ASEAN region in April 2020. The prevailing winds blew mainly from the east or southeast over the eastern half of the Mekong sub-region, and from the southeast or south in the western half of the sub-region. In early April 2020, there was a gradual increase in shower activities over the eastern half of the sub-region. By the latter half of the month, an increase in shower activities were also observed over the western half of the sub-region. In the southern ASEAN region, scattered showers fell over most parts of the region. The prevailing winds blew mainly from the northeast or east over areas north of the equator and remain light and variable in direction over areas to the south.

Figure 1: Average Daily Rainfall for Apr 2020. (Source: JAXA GsMaP)

1.2 In April 2020, hotspot activities continued to remain elevated in the Mekong sub-region, but the overall hotspot count was lower compared to that of past years. In the southern ASEAN region, the hotspot activities continued to remain subdued.

Figure 2: Hotspot count for the northern ASEAN region for Apr 2013 – 2020. [Note: Hotspot count from year 2019 onward is based on the NOAA-20 satellite, and for the period from year 2013-2018 is based on the Suomi-NPP satellite.]

Figure 3: Hotspot count for the southern ASEAN region for Apr 2013 – 2020. [Note: Hotspot count from year 2019 onward is based on the NOAA-20 satellite, and for the period from year 2013-2018 is based on the Suomi-NPP satellite.]

1.3 In April 2020, hotspot clusters were detected mostly in the northern Mekong sub-region, particularly in Myanmar and northern Lao PDR. These hotspot activities persisted for more than two to three weeks. Isolated hotspot activities were also detected in Cambodia and southern Lao PDR on many days. In the southern ASEAN region, isolated hotspots were detected on some days and were mostly short-lived.

Figure 4: Distribution of hotspots detected based on NOAA-20 satellite surveillance for Apr 2020.

1.4 In terms of fire intensity, the hotspot activities in northern Lao PDR, as well as in several parts of Myanmar recorded higher intensities as compared to other parts of the ASEAN region.

Figure 5: Maximum fire intensity based on NOAA-20 satellite surveillance in Apr 2020.

1.5 The smoke haze observed in the Mekong sub-region was less extensive in April 2020 as compared to March 2020. In April 2020, persistent smoke haze was observed mainly over the northern parts of the sub-region, particularly over Myanmar, northern Lao PDR, and northern and central Thailand. Over these areas, dense smoke haze was observed on many days during the first fortnight of the month, but an increase in shower activities brought a gradual improvement to the haze situation in the second half of the month. The air quality readings in northern and central Thailand improved from the Unhealthy to Very Unhealthy levels to the Excellent to Satisfactory levels by end-April 2020. Showers in the later part of the month had also brought an improvement to the haze situation in northeastern Cambodia and southern Lao PDR. In the southern ASEAN region, no significant smoke haze was observed except for localized smoke plumes emanating from some hotspots in Riau, Sumatra and the east coast of Peninsular Malaysia.

Figure 6: Number of days with moderate to dense smoke haze observed over an area based on satellite imageries, ground observations and air quality reports in Apr 2020.

April 8, 2020

Review of Regional Haze Situation for March 2020

1.1 While Northeast Monsoon conditions continued to prevail over the ASEAN region in March 2020, the prevailing winds over the Mekong sub-region during the month were mostly blowing from southeast or southwest. Despite an increase in isolated showers over the eastern parts of the Mekong sub-region, the weather over the sub-region remained largely dry during this period. In contrast, scattered showers fell over the southern ASEAN region, particularly over areas south of the equator.

Figure 1: Average Daily Rainfall for Mar 2020. (Source: JAXA GsMaP)

1.2 Scattered hotspots were detected in the Mekong sub-region, while hotspot activities remained subdued in the southern ASEAN region. In terms of the hotspot count, Lao PDR recorded one of the highest number of hotspots in March 2020 in comparison with previous years. Elsewhere in the region, there was no significant trend observed during the review period.

Figure 2: Hotspot count for the northern ASEAN region for Mar 2013 – 2020. [Note: Hotspot count from year 2019 onward is based on the NOAA-20 satellite, and for the period from year 2013-2018 is based on the Suomi-NPP satellite.]

Figure 3: Hotspot count for the southern ASEAN region for Mar 2013 – 2020. [Note: Hotspot count from year 2019 onward is based on the NOAA-20 satellite, and for the period from year 2013-2018 is based on the Suomi-NPP satellite.]

1.3 In March 2020, persistent hotspots were detected in many parts of the Mekong sub-region, particularly in Myanmar, northern and southern Lao PDR, parts of northern and central Thailand, northern Cambodia, as well as a few areas in southern Viet Nam. In the southern ASEAN region, hotspots were detected on occasions and these were mostly short-lived.

Figure 4: Distribution of hotspots detected based on NOAA-20 satellite surveillance for Mar 2020.

1.4 Over the aforementioned areas in the Mekong sub-region with persistent hotspots, the intensity of fires was also high relative to the other parts of the ASEAN region.

Figure 5: Maximum fire intensity based on NOAA-20 satellite surveillance in Mar 2020.

1.5 March 2020 saw a further deterioration in the haze situation over the Mekong sub-region, where many areas were enveloped in widespread smoke haze. In particular, dense haze was observed over eastern Myanmar, parts of northern and central Thailand, as well as the northern parts of Lao PDR and Viet Nam, where there were occurrences of transboundary smoke haze. On some days, transboundary smoke haze also affected southern Lao PDR, southern Viet Nam and northern Cambodia. The air quality levels in northern Thailand remained in the Unhealthy to Very Unhealthy range on most days in March 2020. Smoke haze in the Mekong sub-region also contributed to reduced visibility readings across several parts of the sub-region. In the southern ASEAN region, no significant smoke haze was observed except for localized smoke plumes from the short-lived hotspots in central Sumatra.

Figure 6: Number of days with moderate to dense smoke haze observed over an area based on satellite imageries, ground observations and air quality reports in Mar 2020.