Review of Regional Haze Situation for June 2021

1.1 The ASEAN region transitioned to Southwest Monsoon conditions in June 2021, with prevailing winds over regions south of the equator blowing from the southeast while prevailing winds over regions north of the equator blew mainly from the southwest.

1.2 During this period, the monsoon rain band stayed in close proximity to the equator and shower activities were observed over most of the ASEAN region. However, drier conditions persisted in the Lesser Sunda Islands and eastern Java (Figure 1).

Figure 1: Average Daily Rainfall and Mean Wind for June 2021. (Source: JAXA GsMaP and GFS respectively)

 

1.3 The hotspot counts over most of the ASEAN region for June 2021 were comparable to those in previous years. More hotspots were detected in Cambodia and the Philippines compared to previous years while lesser hotspots were detected in Sumatra and Peninsular Malaysia compared to previous years. (Figures 2 and 3)

Figure 2: Hotspot counts for the northern ASEAN region for the month of June (2017 – 2021). [Note: The hotspot counts from 2019 onwards are based on the NOAA-20 satellite, while those from 2017 – 2018 are based on the Suomi-NPP satellite.]

 

Figure 3: Hotspot counts for the southern ASEAN region for the month of June (2017 – 2021). [Note: The hotspot counts from 2019 onwards are based on the NOAA-20 satellite, while those from 2017 – 2018 are based on the Suomi-NPP satellite.]

 

1.4 In June 2021, isolated hotspots were detected in most parts of the southern ASEAN region, contributed by brief periods of drier weather. Isolated to scattered hotspots were also detected in the eastern and central parts of the Mekong sub-region but were alleviated by an increase in shower activities. On the whole, hotspot activities remained relatively subdued in the ASEAN region with no significant smoke haze observed from satellite imagery (Figures 4 and 5).

Figure 4: Distribution of hotspots detected in June 2021 based on NOAA-20 satellite surveillance.

 

Figure 5: Maximum fire intensity in June 2021 based on NOAA-20 satellite surveillance.