The Impact Assessment and Applications Section (IAAS) of Climatology and Agrometeorology Division (CAD) regularly issue this monthly/bulletin which will provide users such as food security managers, economic policy makers, agricultural statisticians and agricultural extension officials with qualitative information on the current and potential effects of climate and weather variability on rainfed crops, particularly rice and corn. This bulletin, entitled “Climate Impact Assessment for Agriculture in the Philippines”, represents a method for converting meteorological data into economic information that can be used as supplement to information from other available sources.
For example, an agricultural statistician or economist involved in crop production and yield forecast problems can combine the assessment with analysis from area survey results, reports on the occurrence of pests and diseases, farmers’ reports and other data sources.
The impact assessments are based on agroclimatic indices derived from historical rainfall data recorded for the period 1951 to the present. The indices, expressed in raw values percent of normals and percentile ranks, together with real time meteorological data (monthly rainfall, in percent of normal), percent of normal cumulative rainfall, as well as the occurrence of significant event such as typhoons, floods and droughts are the tools used in the assessment of crop performance. Crop reports from PAGASA field stations are also helpful.
The narrative impact assessment included in the bulletin depicts the regional performance of upland, 1st lowland and 2nd lowland palay; and dry and wet season corn crops, depending on the period or the season. Tabulated values of normal rainfall and generalized monsoon and yield moisture indices are provided for ready reference. Spatial analysis of rainfall, percent of normal rainfall and the generalized monsoon indices in percentile ranks are also presented on maps to help users visualize any unusual weather occurring during the period. The generalized monsoon indices in particular, are drought indicators; hence, the tables (see Appendices) together with the threshold values can be used in assessing drought impact, if there are any. It also helps assess any probable crop failure.
It is hoped therefore that this bulletin would help provide the decision-makers, planners and economist with timely and reliable early warning/information on climatic impact including the potential for subsistence food shortfalls, thereby enabling them to plan alternate cropping, if possible, food assistance strategies/mitigation measures to reduce the adverse impact of climate and eventually improve disaster preparedness.
Impact assessment for other principal crops such as sugarcane and coconut, for energy and for water resources management, are from time to time will be included in the forthcoming issues of this bulletin.
The IAAS of CAD will appreciate suggestions/comments from end-users and interested parties for the improvement of this bulletin.Definition of Terms
The Generalized Monsoon Index (GMI) helps determine the performance of the rains during the season and serves as a good indicator of potential irrigation supplies. It is a tool used to assess rainfed crops.
The GMI for the southwest monsoon (GMIsw) in an area during June to September is defined as follows:
The GMI for the northeast monsoon (GMIne) in an area during October to January is defined as:
The Yield Moisture Index (YMI) is a simple index that helps the users assess agroclimatic crop conditions during the crop season. The YMI for a particular crop is defined as follows:
AGROCLIMATIC / CROP CONDITION ASSESSMENT
Harvesting of upland palay in most parts of the region had just begun in most parts of the country; good to normal yield is expected in CAR, most parts of Central Luzon, Tayabas, Panay Island, Catbalogan, Zamboanga del Norte, Bukidnon, and ARMM. In contrast, below normal yield may be anticipated in Cagayan Valley and Davao because the crops experienced moisture deficiency from flowering to maturity. Similarly, harvesting of lowland 1st palay has also started in some parts of the country, good to normal yield is anticipated in Infanta, most parts of MIMAROPA, Camarines Norte, Northern Samar, Surigao del Sur and del Norte, while below normal yield is expected in Albay due to moisture stress. Meanwhile, standing rice crops in most areas of the country experienced favorable crop conditions; in some parts, however, insufficient moisture might have caused the crops to suffer moisture stress.
Rainfall assessment for the month of August showed that below to near normal rainfall conditions were experienced over most parts of the country. Moreover, the provinces of Quirino, Pampanga, Aurora, Camarines Norte, Negros Oriental, Bohol, Cebu, Siquijor, Southern Leyte, Camiguin and Misamis Oriental received above normal rainfall.
The weather systems that affected the country during the month were the southwest (SW) monsoon, low pressure areas (LPAs), inter-tropical convergence zone (ITCZ), local thunderstorms, and the passage of two (2) tropical cyclones (TCs), namely: Severe Tropical Storm (STS) “Isang” (August 20–22) and Tropical Storm (TS) “Jolina” (August 24–26). STS “Isang” passed through the vicinity of Batanes area, while TS “Jolina” made landfall in Casiguran, Aurora. Both TCs enhanced the SW monsoon and brought moderate to occasionally heavy rains over Luzon and western Visayas. Moreover, classes and work suspension were declared due to floodings caused by TS “Jolina” in Regions I, II, III, V, CAR, CALABARZON and Metro Manila, based on the report of the National Risk Reduction and Management Council (NDRRMC).
REGION I (Ilocos Region)
The sufficient rainfall received during the month favored standing late-planted upland 1st palay, which was affected by the Southwest Monsoon last month and had only recently recovered. It is also beneficial to the newly planted, lowland 1st palay all over the region.
CAR (Cordillera Autonomous Region)
Harvesting of upland 1st palay had just begun across the region; near normal to normal yield is expected, due to adequate moisture and normal conditions experienced by the crops throughout the entire growing season. Moreover, standing June-planted, upland palay crops are in normal condition
REGION II ( Cagayan Valley)
Harvesting of upland 1st palay had just started across the region; below normal yield is anticipated because the crops experienced moisture stress during their critical stage of growth and development. Standing July- planted lowland 1st palay is in good crop condition because of adequate moisture supply available during the month.
REGION III (Central Luzon)
Harvesting of upland 1st palay is now on-going all over the region; good to normal yield is expected because the crops experienced favorable weather and sufficient moisture supply throughout the growing period. Likewise, ample moisture supply available during the month remains favorable for the standing newly planted, lowland palay as well as the vegetating upland palay.
REGION IV-A (CALABARZON)
Harvesting of lowland 1st palay in Infanta and upland 1st palay in Tayabas has just begun; near normal to above normal yield is anticipated in those areas due to sufficient moisture and favorable weather experienced by the crops from planting to maturity. The significantly adequate rainfall received during the month favored the condition of standing rice crops.
REGION IV-B (MIMAROPA)
Harvesting of lowland 1st palay has just begun across the region; near normal to normal yield is expected because the crops experienced sufficient moisture and normal crop condition during the critical stage of growth. Standing upland and lowland palay in most parts of the region are faring well, but in Romblon and Puerto Princesa, the crops might experience moisture stress due to inadequate rainfall received during the month.
REGION V (Bicol Region)
Normal harvest of lowland 1st palay is expected in Camarines Norte because the moisture supply has been adequate throughout the growing season. However, below normal yield is anticipated in Albay due to moisture stress experienced by the crops during their critical stage of growth. Meanwhile, the standing June-planted lowland palay in Camarines Norte, as well as the newly planted lowland palay in Masbate, shows normal crop conditions due to the sufficient moisture during the month.
REGION VI (Western Visayas)
Sufficient moisture available during the month favors the harvestable upland 1st palay across the region; good to normal yield is expected because of favorable weather and good crop conditions experienced by the crops from planting to maturity. Likewise, weather condition and moisture available during the month remained favorable for standing July-planted, lowland palay.
REGION VII (Central Visayas)
Sufficient rainfall available during the month benefited standing June-planted, upland palay in Mactan as well as July-planted, lowland palay across the region. The crops continued to experience normal condition.
REGION VIII (Eastern Visayas)
Harvesting of lowland 1st palay in Northern Samar, as well as upland palay in Catbalogan, is ongoing; normal yield is expected because the crops experienced normal crop conditions throughout their growing period. Consequently, standing lowland and upland palay crops experienced favorable conditions due to sufficient moisture supply available during the month.
REGION IX (Zamboanga Peninsula)
Harvesting of upland 1st palay has started in Zamboanga del Norte; near normal to normal yield is anticipated because the crops experienced good crop conditions during the critical stage of growth and development. Similarly, the vegetating upland palay in northern parts continue to experience good crop condition because of sufficient moisture available during the month.
REGION X (Northern Mindanao)
Harvesting of upland palay in Bukidnon is now in progress; normal yield is expected this season because the crops experienced normal condition from planting to maturity. Meanwhile, sufficient rainfall received during the month continued to benefit the standing newly planted lowland palay and the flowering upland palay under favorable weather condition.
REGION XI (Davao Region)
Harvesting of upland 1st palay has just started across the region; below normal yield is anticipated due to moisture deficiency experienced by the crops during their flowering stage. However, adequate rainfall received during the month might help the crops recover from moisture stress and probably attain good yield in the next harvest period.
REGION XII (SOCCSKSARGEN)
The standing June-planted, upland 1st palay suffered moisture stress since last month because of very low rainfall received across the region. Below normal yield is anticipated in the next harvest season.
REGION XIII (CARAGA Region)
Harvesting of lowland 1st palay has just begun across the region, particularly in Surigao del Sur; normal to above normal yield is anticipated due to favorable crop condition experienced by the crops during the critical stage of development. Standing lowland palay continued to experience favorable crop condition due to sufficient rainfall received during the month.
While in Surigao del Norte, the harvestable May-planted, lowland 1st palay is expected to be from good to normal yield because the crops experienced slight moisture stress in vegetative stage but recovered during its maturing stage.
ARMM ((Autonomous Region of Muslim Mindanao)
Harvesting of upland 1st palay has just begun across the region; good to normal yield is expected this season because the crops experienced normal crop conditions from planting to maturity. Meanwhile, insufficient moisture available during the month might stress the July-planted, lowland palay.
For Particulars, please contact:
THELMA A. CINCO
Climatology and Agrometeorology Division (CAD)
Telefax No.: 434-58-82