Impacts of Climate Change on Agriculture - Climate Resilient Agriculture for Ensuring Food Security - page 77

of the self-serving economic policies and
ineffective food aid and poverty programs
(Beresford and Fullerton 1989 ).
In Africa, the projected rise in rainfall associ-
ated with global warming is encouraging, espe-
cially since Africa already suffers from severe
rainfall shortages. Therefore, the 10 % increase
in rainfall will help improve crop yields, but it
will not solve Africa's food problems. Water
shortages will persist, and serious crop losses
from pests are expected to continue.
Changes in temperature, moisture, carbon
dioxide, insect pests, plant diseases, and weeds
associated with global warming are projected to
reduce food production in North America. The
extent of alterations in crop yields will depend on
each crop and its particular environmental
requirements. However, improved agricultural
technologies could partially offset decreased
yields.
Additional research is needed on the potential
impacts of climate change, including research on
the temperature-induced degradation of soil,
water, and biological resources and their poten-
tial impact on crop production.
Farmers in North America and Africa also
need to adopt sound ecological resource manage-
ment practices, especially soil and water conser-
vation. These practices would benefi t agriculture,
the environment, farmers, and society, enabling
agriculture to remain productive and offsetting
some of the negative impacts of global warming.
Smaller farms are dependent on timely and
suffi cient rainfall during the monsoon for high
crop yields. However, with the changing climate,
rainfall patterns have become erratic and reduced,
leaving farmers exposed to many risks including
droughts, fl oods, diseases of both crops and ani-
mals, and unpredictable market irregularities
(Venkateswarlu 2009 ). Indeed it is estimated that
every 1 °C increase in temperature is likely to
lead to a 5-10 % reduction in yields of some
crops (Pachauri 2009 ).
Increased temperatures have drastically
affected the rice production due to decrease crop
duration in the Philippines (10 % reduction in
yield in rice per 1 °C rise in temperature) (Peng
et al. 2004 ). An increase of 6 °C in temperature

and precipitation defi cit of 300 mm reduced the
maize yield by 36 % in the European Union
(Ciais et al. 2005 ).
Numerous studies have examined the impacts
of past climatic variations on agriculture. Such
studies have clearly demonstrated the sensitivity
of both temperate and tropical agricultural sys-
tems and nations to climatic variations and
changes. In the temperate regions, the impacts of
climate variability, particularly drought, on yields
of grains in North America and the Soviet Union
have been of particular concern because of their
effects on world food security. In the tropics,
drought impacts on agriculture and resulting food
shortages have been widely studied, especially
when associated with the failure of the monsoon
in Asia or the rains in Sudano-Sahelian Africa. In
the temperate regions, climatic variations are
associated with economic disruptions; in the
tropics, droughts bring famine and widespread
social unrest (Pierce 1990 ).
At lower latitudes, especially in seasonally
dry and tropical regions, crop productivity is pro-
jected to decrease for even small local tempera-
ture increases (1-2 °C), which would increase the
risk of hunger (IPCC 2007 ). Fischer et al. ( 1996 )
projected the most signifi cant negative changes
for developing countries in Asia, where agricul-
tural production declines of about −4 % to −10 %
are anticipated under different socioeconomic
and climate change scenarios.

4.11.2 Quality

According to the IPCC's TAR, “The importance
of climate change impacts on grain and forage
quality emerges from new research. For rice, the
amylose content of the grain, a major determi-
nant of cooking quality, is increased under ele-
vated CO 2 ”. Cooked rice grain from plants grown
in high-CO 2 environments would be fi rmer than
that from today's plants. However, concentra-
tions of iron and zinc, which are important for
human nutrition, would be lower. Moreover, the
protein content of the grain decreases under
combined increases of temperature and CO 2
(Woodward and Kelly 1995 ). Studies using