This monitoring period covers the rainy season in the Philippines, which usually lasts from May to early October. Within this monitoring period, the harvest of main maize ended in September, followed by the harvest of main rice in October. The sowing of second maize and second rice began in October.

The country experienced slightly dryer and warmer weather during this monitoring period. As shown by the agro-climatic indicators, average precipitation dropped by 5% as compared to the 5YA, despite of several typhoons that made landfall over the Philippines. One of them, named Chanthu, brought record precipitation and decreased the NDVI for the country to some extent. The temperature increased by 0.4℃ (TEMP) and the radiation by 7% (RADPAR). The estimated biomass remained near average (BIOMSS +1%). The CALF did not change and the VCIx value was as high as 0.96. All of these indicate that the crop conditions were close to normal in the Philippines.

With respect to the crops at the local scales, the NDVI for 12.9% (orange color) of the arable cropland decreased by about 0.2 units in August and by about 0.1 in October. Furthermore, about 54.8% of the cropland shared stable and close-to-average NDVI. These croplands (light green color) were mainly located in northern Luzon Island and Mindanao Island. The rest of the croplands (dark green and blue color) remained slightly below average for most of the monitoring time, and these areas were mainly clustered in southern Luzon Island and northern Visayas Island.

Regional analysis

Based on the cropping systems, climatic zones and topographic conditions, three main agro-ecological regions can be distinguished for the Philippines. They are the Lowlands region (northern islands), the Hilly region (Island of Bohol, Sebu and Negros), and the Forest region (mostly southern and western islands). All the regions are characterised by a stable cropped arable land fraction (CALF almost 100%) and a high maximum VCI value (VCIx ⩾0.96).

For the Lowland region, the rainfall decreased by 11% (RAIN), while the temperature increased by 0.4℃ (TEMP) and radiation increased by 7% (RADPAR). The estimated biomass dropped by 1% (BIOMSS). As shown by the NDVI profile, the negative NDVI departure increased throughout July and reached a maximum at the end of September, while the average precipitation and temperature in the region were at normal levels during the same period. Thus, the large negative departures in NDVI can be mainly attributed to cloud cover in the satellite images. In addition, warmer weather and more sunshine had a positive impact on the crops, bringing the NDVI values back to average levels by the end of October. As a result, the crop condition in this region is estimated to be generally normal.

The Hilly region experienced a slightly wetter and warmer period. The rainfall was slightly higher than average by 1% (RAIN) and temperature increased by 0.5℃ (TEMP). The radiation was higher than average by 6% (RADPAR) and resulting biomass was higher than average by 2% (BIOMSS) as well. However, the NDVI was fluctuating below  average since the end of July, which indicates that the crop conditions in this region are unfavorable.

In the Forest region, the precipitation was higher than average (RAIN +2%), accompanied by above-average temperature (TEMP, +0.4℃) and above-average radiation (RADPAR, +6%). The resulted biomass increased by 2% (BIOMSS). The VCIx value reached 0.96 and the CALF stayed at 100%. As shown by the NDVI profile, the NDVI for the region remained stable, slightly below average. All the indicators suggest that the crop growth for this region is normal.

Figure 3.35 Philippines' crop condition, July-October 2021

(a) Phenology of major crops

(b) Crop condition development graph based on NDVI     (c) Maximum VCI

(d) Spatial NDVI patterns compared to 5YA      (e) NDVI profiles

(f) Time series temperature profile (left) and rainfall profile (right)

(g) Crop condition development graph based on NDVI (left) and time series rainfall profile (right) in Lowlands region

(h) Crop condition development graph based on NDVI (left) and time series rainfall profile (right) in Hilly region

(i) Crop condition development graph based on NDVI (left) and time series rainfall profile (right) in Forest region

Table 3.61 Philippines' agroclimatic indicators by sub-national regions, current season's values and departure from 15YA, July-October 2021

Table 3.62 Philippines' agronomic indicators by sub-natioanal regions, current season's values and departure from 5YA, July-October 2021