Most of southern West Africa is under relatively dry conditions from April to July. The planting of paddy, maize, and vegetables started from the beginning of May and June. Figure 2.1 illustrates agroclimatic and agronomic indicators for the MPZ for the reporting period.

Compared with average conditions, the region suffered a minor rainfall deficit in the order of 6% accompanied by slightly below average temperature (TEMP, -0.3°C) and radiation (RADPAR, -1%). Major countries in West Africa recorded a rainfall deficit, including Ghana (RAIN, -16%), Gambia (-12%), Cote d'Ivoire (-26%), Cameroon (-10%), and Guinea Bissau (-25%). The major country with marked rainfall excess is Burkina Faso (+35%), while Nigeria (+2%) received an average amount.

The rainfall profiles and clusters show that rainfall deficits occurred throughout the region after the month of May up to the last week of June; after July, an increasing trend is observed. About 3.8% of the area in the southern part of the MPZ received excess rainfall up to 30 mm/dekad in May and deficits up to -10mm in the month of June. In 79.5% of the MPZ, in areas east, west, north and central, close to average rainfall occurred up to the last week of June, after which a positive departure (up to 30 mm) occurred. About 16.7% of the area, located in the southern part of the MPZ, underwent dekad rainfall deficits up to 20 mm in June. The whole region experienced slightly below average temperature (TEMP, -0.3°C).

The sudden increase in rainfall in July compared with the average is confirmed by maximum VCI, for which low values occur in the small patch of northern part of Nigeria along the border with Niger. This is also where low VHI values tend to concentrate. The very high VCI values are seen in Nigeria, Ghana, Benin, and Togo. Two additional crop related indicators (fraction of cropped arable land (CALF) and biomass production potential (BIOMSS)) departures, both expressed as the departure from the average of the recent five seasons only, confirm a slight increase (1%) in average production potential. High biomass potentials occur in small patches in north, east, and central parts of Nigeria, north Ghana, and the south part of Burkina Faso (Sahel). Low biomass potential is seen in Cote d'Ivoire, southern Ghana, the southern part of Togo, southern Benin, and in Guinea Bissau.

Altogether the indicators in West Africa show that the crop production is likely to be slightly above average (that is, a 1% increase), and probably well above average in the Sahelian north, which benefited from an early start of the season.

a. Spatial distribution of rainfall profiles

b. Profiles of rainfall departure from average (mm)

c. Profiles of temperature departure from average (°C)

d. Maximum VCI

e. Cropped arable land

f. Biomass accumulation potential departure

g. VHI minimum