Review of Regional Haze Situation for February 2022

1.1 The ASEAN region continued to be influenced by Northeast Monsoon conditions in February 2022. Over areas north of the equator, the prevailing winds blew mainly from the northeast even though the winds were relatively weaker and more variable in direction over the Mekong sub-region. For areas south of the equator, the prevailing winds blew mostly from the west or northwest (Figure 1).

1.2 Dry conditions persisted over the Mekong sub-region throughout the review period of February 2022, except for isolated shower activities in the southern parts of the sub-region on some days. Elsewhere in the ASEAN region, rainy weather was observed in many areas. However, parts of Sumatra, Borneo, and the Philippines experienced brief periods of drier weather.

Figure 1: Average Daily Rainfall and Mean Winds for February 2022. (Source: JAXA GsMaP and GFS, respectively)

 

1.3 Prolonged dry conditions over the Mekong sub-region led to an increase in overall hotspot activity in February 2022. While isolated to scattered hotspots were detected in most parts of the sub-region on several days, the hotspot counts were generally lower this year compared to previous years (Figure 2). In the southern ASEAN region, hotspot activity was generally subdued, with only isolated hotspots detected in Sumatra and Kalimantan. The hotspot counts were also lower compared to previous years (Figure 3).

Figure 2: Hotspot counts for the northern ASEAN region for the month of February (2018 – 2022). [Note: The hotspot counts from 2019 onwards are based on the NOAA-20 satellite, while those from 2018 are based on the Suomi-NPP satellite.]

 

Figure 3: Hotspot counts for the southern ASEAN region for the month of February (2018 – 2022). [Note: The hotspot counts from 2019 onwards are based on the NOAA-20 satellite, while those from 2018 are based on the Suomi-NPP satellite.]

 

1.4 In view of the increase in hotspots and escalating smoke haze situation in the Mekong sub-region, ASMC activated Alert Level 2 for the sub-region on 11 February 2022. From the middle of the month, persistent hotspots and a few localised smoke plumes were detected in many parts of the Mekong sub-region, particularly over Myanmar, northern Cambodia, and southern Lao PDR (Figures 4 and 5). By the end of the month, moderate to dense smoke haze was observed to emanate from persistent hotspot clusters in Myanmar, northern Thailand, northern Cambodia, and southern Lao PDR (Figures 6 and 7).

Figure 4: Distribution of hotspots detected in February 2022 based on NOAA-20 satellite surveillance.

 

Figure 5: Maximum fire intensity in February 2022 based on NOAA-20 satellite surveillance.

 

Figure 6: Number of days with moderate to dense smoke haze observed in February 2022 based on satellite imagery, ground observations, and air quality reports.

 

Figure 7: Moderate to dense smoke haze observed over Myanmar and northern Thailand on 27 February 2022, based on NOAA-20 satellite imagery.