SAHEL WEATHER AND CROP SITUATION 1997

Global Information and Early Warning System on food and agriculture

Report N^o1 - 13 June 1997

THE RAINY SEASON HAS STARTED EARLY IN THE WESTERN PART OF THE SAHEL

SUMMARY
SITUATION BY COUNTRY
SITUATION MAP AS OF 10 JUNE 1997
SOURCES OF INFORMATION
SOME DEFINITIONS

Click on one country or its name to consult the situation of this country

SUMMARY

Rains started in late March/early April in Burkina Faso and became abundant over the south and centre in late May. The rainy season started in April in the extreme south of Chad, Mali and Niger. First significant rains reached the east of Guinea Bissau and the south-east of Senegal in early May and eastern The Gambia in late May. The last Meteosat sattelite image for the first dekad of June indicates that cloud coverage progressed northwards over the Sahel region, especially in its western parts. Substantial rains have covered most parts of Senegal, The Gambia and western Mali. They also reached southern Mauritania, marking an early start of the rainy season in the western part of the Sahel. Rains decreased somewhat in central Burkina Faso and western Niger but increased in south-western and central Niger and some first rains may have been received in the Sahelian zone of Chad.

Land preparation and planting are progressing following the onset of the rains. Dry planting is also underway, notably in Senegal. Seasonably dry conditions prevail in Cape Verde and northern parts of Mali, Niger and Chad.

Grasshoppers are reported in Ouaddaï region of Chad. Moderate numbers of solitary Desert Locust adults and perhaps a few small groups will move west across the Red Sea to the interior of Sudan and perhaps continue towards West Africa over Chad and Niger if they find dry conditions en route. Small-scale egg laying could occur with the onset of the rains.

SITUATION BY COUNTRY

BURKINA FASO CAPE-VERDE CHAD GAMBIA GUINEA-BISSAU MALI MAURITANIA NIGER SENEGAL

SOME DEFINITIONS

In these reports, reference will be made to four different eco-climatic zones based on the average annual precipitation and agricultural features, i.e. Sahelian zone, Sudano-Sahelian zone, Sudanian zone and Guinean zone. They are shown in the map and described below:

Sahelian zone: Where average annual precipitation ranges between 250 and 500 mm. This zone is at the limit of perennial vegetation. In parts where precipitation is less than 350 mm, only pastures and occasional short-cycle drought-resistant cereal crops are grown; all cropping in this zone is subject to high risk.

Sudano-Sahelian zone: Where average annual precipitation ranges from 500 to 900 mm. In those parts of this zone where precipitation is less than 700 mm, mostly crops with a short growing cycle of 90 days are generally cultivated predominantly sorghum and millet.

Sudanian zone: Where average annual precipitation ranges from 900 to 1 100 mm. In this zone, most cereal crops have a growing cycle of 120 days or more. Most cereals, notably maize, root and cash crops are grown in this zone.

Guinean zone: Where average annual precipitation exceeds 1 100 mm. Guinea-Bissau and a small area of southern Burkina Faso belong to this zone, more suited to root crop cultivation.

Reference will also be made to the Intertropical Convergence Zone (ITCZ), also known by its trace on the earth's surface, called the Intertropical Front. The ITCZ is a quasi-permanent zone between two air masses separating the northern and southern hemisphere trade winds. The ITCZ moves north and south of the equator and usually reaches its most northerly position in July. Its position defines the northern limits of possible precipitation in the Sahel; rain-bearing clouds are generally situated 150-200 km south of the Intertropical Front.