From October to January, the reporting period covers the harvest of the main rice crop and the start of the second rice season. According to CropWatch agroclimatic indicators, Thailand experienced average weather conditions compared to the last 15 years. The radiation (RADPAR +4%) was slightly above average, while rainfall (RAIN -8%) was below average. Temperature was unchanged (TEMP +0.0°C). The combination of these agroclimatic parameters resulted in a below average estimate for biomass accumulation (BIOMSS -4%). According to the NDVI development graph, the crop conditions were slightly below average. The NDVI departure clustering and the corresponding profiles show that for 77.4% of the cropland the crop conditions were close to average. For the remaining cropland, crop conditions were below average before November. However, the strong negative departures in NDVI can be attributed to cloud cover in the satellite images. Areas which trended below average were located in the southern hills (including Surat Thani, Chumphon, Ranong and Prachuap Khilikhan). National VCIx value was at 0.93 and CALF remained near average. Considering the unfavorable conditions described in the November 2021 bulletin and the conditions of this monitoring period, the crop outputs are assessed as slightly below average. For second rice, average weather indicators lead to fair crop condition.

Regional analysis

The regional analysis below focuses on some of the already mentioned agro-ecological zones of Thailand, which are mostly defined by the rice cultivation typology. Agro-ecological zones include Central double and triple-cropped rice lowlands (115), South-eastern horticulture area (116), Western and southern hill areas (117) and the Single-cropped rice north-eastern region (118).

Compared to the 15YA, Central double and triple-cropped rice lowlands experienced cooler and drier conditions. Radiation (RADPAR +5%) was above average accompanied by lower temperatures (TEMP -0.1°C) and lower rainfall (RAIN -10%). This condition led to an unchanged estimate for BIOMSS (BIOMSS +0%). The NDVI development graph shows that crop conditions were below the five-year average for most of the monitoring period, although the high VCIx value at 0.92 indicates that crops were favourable during the main growing season and the peak growth period. All in all, conditions were slightly below average.

Indicators for the South-eastern horticulture area shows that temperature (TEMP -0.2°C) was below average accompanied by higher radiation (RADPAR +3%) and rainfall (RAIN +18%). They led to a slightly above-average estimate for BIOMSS (BIOMSS +4%). According to the NDVI development graph, however, the crop conditions were slightly below average during this monitoring period.  VCIx was at of 0.92. All in all, conditions were slightly below average.

Agroclimatic indicators show that the conditions in the Western and southern hills were slightly below average: rainfall (RAIN, -7%) was below average, while and radiation (RADPAR +3%) was above average. Accompanied with average temperature (TEMP -0.0°C), the weather conditions led  to a 4% decrease in BIOMSS. According to the favorable VCIx value of 0.95, crop conditions were assessed as close to average.

In the Single-cropped rice north-eastern region precipitation was below average by 16%, while radiation was above average by 5%. The temperature was close to average. All these agroclimatic indicators led to a decreased potential biomass (BIOMSS -6%). According to the NDVI development graph, the crop conditions were close to average. Considering the favorable VCIx value of 0.91, the crop conditions are assessed as normal.

Figure 3.39 Thailand’s crop condition, October 2020- January 2021

(a). Phenology of major crops

(b). Time series temperature profile. (c). Time series rainfall profile

(d) Crop condition development graph based on NDVI  (e) Maximum VCI

(f) Spatial NDVI patterns compared to 5YA   (g) NDVI profiles

(h) Crop condition development graph based on NDVI (Central double and   triple-cropped rice lowlands (left) and Western and southern hill  areas (right))

(h) Crop condition development graph based on NDVI (South-eastern horticulture   area (left) and Single-cropped rice   north-eastern region (right))

Table 3.67 Thailand's agroclimatic indicators by sub-national regions, current season's values and departure from 15YA,October 2021- January 2022

Table 3.68 Thailand's agronomic indicators by sub-national regions, current season's values and departure,October 2021- January 2022