Attachments
Highlights
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Southern and central areas continued to receive well above average rains in January
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Poor rainfall was received in western and north-eastern SADC and Madagascar
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The Fall Armyworm has been confirmed in 7 countries in the region. The severity of the impact on regional crop production is yet to be established
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Tropical cyclones Carlos and Dineo affected the region in early to mid-February. The impacts of Cyclone Dineo are severe, particularly in southern Mozambique
Regional Summary
After a slow start to the rains in many areas early in the season, rains improved in December 2016 in the central and south-eastern parts of the region, then intensified considerably to well above average in January 2017. Much of Botswana, eastern Namibia, south-eastern Angola, southern half of Zambia, Zimbabwe, southern and central Mozambique, southern and central Mozambique, and north-western half of South Africa received at least one and half to two times the normal amount of January rainfall (Figure 1, blue oval #1). These high rains led to crops receiving sufficient soil moisture for good harvest potential in many area, although in some areas, the rains resulted in flooding, waterlogging and leaching of soil nutrients. The high rains also affected operations to combat the regional Fall Armyworm outbreak, due to dilution and washing away of chemicals.
In contrast to the heavy rains in central and southern areas, many of the western and north-eastern parts of the region, as well as eastern Madagascar, received well below average rainfall (Figure 1: red ovals #2, #3, and #4). In many of these areas, the rainfall received was less than a third of the normal January rainfall. Areas affected include western Namibia, western Angola, north-eastern Tanzania, parts of north-eastern Mozambique and eastern Madagascar. The poor rains, combined with high temperatures in some of these areas in January, likely negatively affected any cereal crops grown there.
The first 10 days of February provided a slight reprieve, with reduced rainfall amounts being received in southern Mozambique, northern South Africa and southern Zimbabwe (Figure 2), after weeks of persistent rains. Such short breaks in rainfall are essential to allow optimal crop growth, facilitate weeding, as well as reduce leaching and waterlogging. Most other areas, excluding western parts of the region, received above average rainfall during this period. In many parts of Botswana, Mozambique, South Africa and Zimbabwe the total rainfall for the 41-day period from 1 January to 10 February 2017 alone was more than what is typically received from January to March combined.
The high amount of rainfall that was received in the central and southern areas has generally been sufficient for crop agriculture. An analysis of the Water Requirements Satisfaction Index (WRSI), a model that indicates the extent to which crops have received the water they require throughout the season, suggests that cereal crops grown in the southern parts of the region have this year received better rainfall distribution rainfall than usual, well suited to crop production (green areas, Figure 3). These areas include Botswana, eastern Namibia, northern and central South Africa, Swaziland, southern Mozambique, and southern Zimbabwe. The higher than average WRSI in these areas implies improved potential for good harvests this season. This positive harvest potential only relates to crop water availability however, and the region is facing other challenges that may reduce the good expectations. While many other areas are showing near average WRSI conditions (grey colours, Figure 3), a few areas have below average crop water satisfaction due to the persistent dry conditions that have been observed there (orange colours, Figure 3). These areas include western Angola, parts of north-western Namibia, much of Tanzania, parts of northern Mozambique, eastern and southern Madagascar, and eastern South Africa. Crop production is likely to be affected in many of these areas, as dry conditions have been experienced through much of the current season. In Tanzania, the first season crop in the bimodal areas was the more severely affected, while the slightly improved January rains in the unimodal areas helped to improve the crop outlook.
The good rains in most areas have also facilitated significant improvement of vegetation, after two consecutive poor rainfall seasons led to degradation of pastures. The satellite-based vegetation index (Figure 4), which was showing well below average vegetation conditions earlier in the season, is now showing well above average vegetation conditions in most areas except western Namibia, south western Angola, southern South Africa, eastern Madagascar, parts of northern Mozambique, and Tanzania. These are mainly areas that were affected by poor rains as indicated in the previous sections of this report. The above average vegetation conditions in Figure 4 are denoted by green and blue colours, while below average conditions are shown in brown and orange.