Agriculture Reference
In-Depth Information
Some adverse effects of climate change are water related. Many of the world's
most water-stressed areas will get even less water and in less-predictable patterns.
Water availability is expected to fall in East Africa, the Sahel, and southern Africa,
with large productivity losses in food production. Some projections for East Africa
suggest that productivity losses may be as much as 33, 20, and 18% for maize, sor-
ghum, and millet, respectively (UNDP 2006). Climate change may also accelerate
glacial melt, reducing water availability for particular areas in East Asia, South Asia,
and Latin America and may even disrupt monsoon patterns in South Asia, with enor-
mous consequences for food security.
At the global level, the world is expected to be able to continue to feed itself
for the next century, even in the presence of anticipated climate change. However,
this outcome will be achieved through increased production in developed countries
located in temperate climates, which mostly benefit from climate change, especially
in high-rainfall temperate areas where moderate increases in CO
2
levels may actu-
ally stimulate plant growth. Increased production in temperate climates compensates
for reduced production in tropical and subtropical climates (Parry et al. 2004). This
begs the question of food access and affordability—how will the poor be able to
purchase food they can no longer produce for themselves? Globalization of food dis-
tribution is unlikely to be the answer: With few exceptions, food flows from surplus
to deficit areas only when the latter can pay for it.
As climate change continues to unfold, however, it is possible that agriculture
may become less productive even in temperate climates. In these areas, it appears
that there initially may be a parabolic relationship between temperature and impacts
(benefits at lower temperature increases, damages at higher increases). Beyond an
approximate 3 to 4°C increase in GMT (global mean temperature), however, most
studies show increasing adverse impacts. It appears that, beyond several degrees of
GMT increase, damages are likely to be adverse, increasing, and ubiquitous (Hitz
and Smith 2004).
The future impacts of climate change need to be incorporated into development
planning. They need to be taken into account when selecting priorities for agricul-
tural and resource management research and in the design of water storage and con-
trol investments. Research and investment can help some farm communities adapt
to the adverse effects of climate change through advances in the management of
energy, soils, water, livestock, and crops. For some communities, however, eventual
out-migration appears to be the only solution. Issues of climate change are further
analyzed in Chapter 16.
eneRgy InsecuRIty
Questions of energy insecurity pose further threats to sustainable food production.
Higher energy prices make manufacturing and applying fertilizer, running farm
machinery, pumping water, and transporting inputs and marketing products more
expensive. Other things being equal, this is likely to result in reduced input use, less irri-
gation, lower yields, higher marketing margins, and higher food prices for consumers.
There can be little doubt that energy prices will be higher in the future than they
have been for the past several decades. Higher energy prices will particularly affect
