Review of Regional Haze Situation for November 2021
1.1 In November 2021, the inter-monsoon conditions gradually made way for the Northeast Monsoon over the ASEAN region. The prevailing low-level winds over the northern ASEAN region blew mostly from the northeast or east while the winds over most parts of the southern ASEAN region were light and variable in direction. Wet weather conditions were observed over most parts of the ASEAN region, except for the northern parts of the Philippines as well as the northern, western and central parts of the Mekong sub-region where conditions were persistently drier. Overall, the observed rainfall amount was higher over the coastal areas of central Viet Nam, the southern parts of Thailand and the coastal areas of northern Peninsular Malaysia (Figure 1). Due to the heavy rainfall, floods affected several southern Thailand and central Viet Nam provinces in November 2021.
1.2 For the November review period, overall hotspot activities were mostly subdued due to the wet conditions over the ASEAN region. The hotspot counts over the region for 2021 were mostly lower or comparable to those in previous years (Figures 2 and 3).
1.3 During the review period, isolated to scattered hotspots were detected mainly in the Mekong sub-region and central Sumatra. While these hotspots were mostly short-lived, hotspots were relatively more persistent in the southern parts of Myanmar, northern Viet Nam and central Thailand. On most days, no smoke plumes were discernable.