Review of Regional Haze Situation for January 2020

1.1 In Jan 2020, Northeast Monsoon conditions prevailed over the ASEAN region. During this period, which is the traditional dry season of the Mekong sub-region, persistent dry weather prevailed. In the southern ASEAN region, there were scattered rain showers on most days but there were also occasional dry periods in some areas, including Peninsular Malaysia, northern and central Sumatra (Fig. 1).

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

1.2 In Jan 2020, the number of hotspots detected in the Mekong sub-region was higher than the same period in 2019 (Fig. 2).

Figure 2: Hotspot count for the northern ASEAN region for Jan 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 the southern ASEAN region, hotspot activities remained generally subdued (Fig. 3).

Figure 3: Hotspot count for the southern ASEAN region for Jan 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.]

1.4 There were persistent hotspots detected in Cambodia, particularly in the northern and western provinces. Clusters of hotspots were also detected in northern, northeastern and central Thailand, eastern Myanmar, and southern parts of Lao PDR and Viet Nam (Fig. 4). In the southern ASEAN region, there were occasional isolated hotspots detected mainly in Peninsular Malaysia, Sumatra and Kalimantan.

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

1.5 Based on NOAA-20 satellite surveillance, hotspots with moderate to high fire intensity were detected mostly in northern Cambodia, central Thailand, eastern Myanmar, Lao PDR and southern Viet Nam. Some of these hotspots in northern and central Thailand and Cambodia emitted significant smoke haze on a number of days in Jan 2020.

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

1.6 Persistent hazy conditions were observed mainly in northern and central Thailand, and Cambodia. In eastern Myanmar, northern Lao PDR and southern Viet Nam, smoke haze was observed on some days. Blown by the prevailing winds, transboundary transport of smoke haze was observed on a few days from northern Thailand to northern Lao PDR, and from Cambodia to eastern Thailand.

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 Jan 2020.