Combating Desertification in Kenya - Combating Desertification in Asia, Africa and the Middle East - page 134

of the western and eastern sides of the Rift Valley have higher rainfall than the
Rift Valley floor. “Relief” rainfall occurs on the windward side of high areas
while 'convectional' rainfall is experienced in predominantly flat areas, especially
near large water bodies like Lake Victoria. Further, the seasonal northward and
southward movement of the inter-tropical convergence zone (ITCZ) has enormous
influence on the climatic condition of the country. ITCZ produces two rainy
seasons - March-May (long rains) and October-November (short rains). The coastal
belt is relatively wet with more rainfall in the south. The Nyika plateau is generally
arid and semi-arid. The highlands receive moderate to very heavy rainfall. The
mean annual rainfall ranges between 250 and 1,000 mm in dry lands. Although
the rains are experienced in two distinct seasons, they are erratic in both temporal
and spatial terms. The temperatures are relatively high and account for annual
potential evaporation, which is often above 2,500 mm. The rainfall and the potential
evaporation have been the cause of frequent crop failure in the drylands.
Climatic variation is the main cause of droughts in Kenya. According to the
Intergovernmental Panel on Climate Change Third Assessment Report, 2001,
climate will be associated with rise of mean temperatures by the year 2025. The
change is likely to increase the intensity and frequency of drought. Droughts that
have occurred in Kenya have caused heavy losses in terms of crop failure, deaths of
livestock and human beings and heavy investments for purchase of relief food. It is
anticipated that the projected climate change by the year 2025 will exacerbate the
losses already experienced due to drought.

1.3 Arid and Semi Arid Lands (ASALs)

Over 88 % of Kenya's total land is classified as Arid and Semi Arid Lands (ASALs)
that fall under three Agro-Ecological Zones (Fig. 7.1 ). This land supports 26-30 %
of the total population: 50 % of the livestock sector as well as the wide variety of
the wildlife that forms the basis of Kenya's tourism industry.
Sixty seven percent (67 %) of the total red meat produced in the country comes
from the ASALs and is produced from a livestock population estimated at 8.9
million beef cattle, 5.9 million sheep and 7.7 million goats and 0.85 million camels.
An assessment of Kenya rangelands indicates that, over the country as a whole,
perennial grass cover has decreased whereas annual grass, woody cover and the
amount of bare ground have increased. The human population in ASALs is growing
at a faster rate than in the high potential areas. The growth is heavily influenced
by natural increase and migration of people from the high potential areas mainly
in search of land and employment opportunities. The major challenge now is
how to sustain ASAL productivity while simultaneously providing sustenance or
livelihood for more people. In Kenya, rural dryland populations are dependent on
the environment/natural resource base for food, water and fuel hence degradation
of these assets makes it increasingly difficult for populations to obtain their basic
needs there by accelerating the incidence of poverty.