The semi-arid zone makes up about 21 % of the lowlands. Annual temperatures tend to be cooler than in the arid zone (more representative of the 20Â°C isotherm) and rainfall (400 to 700 mm/year) is bimodal except in the Nuer region, which is under a unimodal regime.Soils include Xerosols and volcanics.he climate regimes are defined in terms of interactions between temperature and precipitation that largely define plant growing periods and variation in human exploitation patterns. This review closely follows Westphal (1975: pp 18-27), Workineh Degefu (1987) and EMA (1988). Figure 1.1.
Sleepwalking is far more common in kids than in adults, as most sleepwalkers outgrow it by the early teen years. It may run in families, so if you or your partner are or were sleepwalkers, your child may be too. Other factors that may bring on a sleepwalking episode include: lack of sleep or fatigue.
The causes of sleepwalking are many, and share many similarities with sleep terrors, which explains why many people experience both sleep disorders at some point in their lives rather than just one or the other.