During this monitoring period, the harvest of second rice and second maize was concluded in April and May respectively. It was followed by the planting period for both main maize and main rice. The Philippines experienced generally wetter and relatively cooler weather conditions than normal. Compared to the average of the same period of the past 15 years, precipitation was 18% higher, average temperature was 0.2℃ lower, while the radiation was basically at the average level. Abundant precipitation comboined with average temperature and average radiation is generally beneficial to the crop growth and biomass accumulation, which resulted in a higher potential biomass (BIOMASS, +5%). This is consistent with the result shown by the NDVI time series graph. NDVI kept close to the average except for late June. That drop was presumeably due to cloud cover in the satellite images. According to the NDVI departure cluster graph, there are generally four patterns: 1) about 67.1% cropland (in dark green color) experienced a near-average NDVI during the monitoring period, indicating a normal crop growth in these regions, which was distributed all around the country. 2) around 17.1% of the cropland (in orange color) underwent a sudden NDVI drop in late June and kept a near-average NDVI in other times. These regions were mainly located in southern Luzon Island and Mindoro. 3) around 15.8% cropland (in blue color and light green) experienced a sudden NDVI drop in April and May and kept a slightly below-average NDVI at other times. These regions were mainly distributed in Mindanao Island. As mentioned above, these NDVI drops were artifacts in the satellite images. Considering the high CALF index (100%) and high VCIx index (0.95), the crop growth was normal during this monitoring period.

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 characterized by a stable cropped arable land fraction (CALF almost 100%) and a high maximum VCI value (VCIx ⩾0.95).

The lowland region had about 5% higher cumulative precipitation, 0.3℃ lower average temperature, and 2% higher radiation. Higher precipitation and more sunshine with near average temperature are beneficial to crop growth and biomass accumulation, resulting a higher potential biomass (BIOMSS +5%). As for NDVI time series graph, the NDVI was above and close to average before mid-June. Although a sudden drop occurred in late June, this drop was most likely caused by cloud cover in the satellite images. Therefore, the crop growth in this region was generally normal.

For the hilly region, cumulative precipitation was significantly higher by about 48%, temperature was about 0.7℃ lower, and radiation was about 3% lower than average. Abundant precipitation resulted in a higher biomass (BIOMSS +6%) in this region as well. As shown by NDVI time series graph, crop NDVI recovered to average levels in early April and kept close to average until mid-June. The subsequent NDVI drop was the result of a sudden NDVI drop over orange regions in early July, which is likely to have been caused by cloud cover as well. Crop growth in this zone was slightly below the average.

For the Forest region, the precipitation was higher by about 29%, average temperature was lower by about 0.3℃, radiation was higher by about 2%, which resulted in a higher biomass (BIOMSS +4%). According to the NDVI time series graph, the crop NDVI was below average before May and recovered to average in May. However, it declined again and kept below and close to average until the end of this monitoring period. Although the NDVI drop can partly be attributed to cloudy weather as well, the continuous below-average NDVI indicates slightly lower than normal crop growth conditions for this region.

Figure 3.35 Philippines' crop condition, April - July 2022

(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 in Lowland region (left) and in the Hilly region (right)

(h) Crop condition development graph based on NDVI in Forest region

Table 3.61 Philippines' agroclimatic indicators by sub-national regions, current season's values, and departure from 15YA, April - July 2022

Table 3.62 Philippines' agronomic indicators by sub-national regions, current season's values, and departure from 5YA, April- July 2022