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Chapter Three Impacts of Global Climate Change

increasing the frequency of extreme weather events. Droughts, floods, pest outbreaks, ocean
warming, and acidification not only reduce food supplies but also drive up food prices, there-
by exacerbating malnutrition issues—particularly the risk of micronutrient deficiencies. For
regions reliant on seafood as a primary protein source, the impacts of climate change fur-
ther intensify these challenges, posing additional threats to global food security and human
health.
(1) Impacts of Climate Change on Agricultural Production
Climate change directly affects agricultural production through multiple pathways,
leading to declines in crop yields and quality, which in turn jeopardize global food safety.
【1】Changes in precipitation patterns
Climate change has led to significant alterations in precipitation patterns, with many
regions experiencing extreme droughts or flood disasters. In arid areas, prolonged water
scarcity prevents normal crop growth, resulting in substantial yield reductions; while water-
logged areas suffer from soil oversaturation or standing water, causing root hypoxia and even
triggering pest outbreaks. For instance, drought issues in sub-Saharan Africa have severely
impacted local food production, leading to food shortages and famines.
2.Rise in Temperature
Global warming has caused temperature increases, particularly in tropical and subtrop-
ical regions, where high temperatures negatively affect crop growth cycles and yields. Ele-
vated temperatures accelerate crop maturation processes, shorten growth cycles, and reduce
yields; simultaneously, high temperaturesIt also increases the water demand of crops, further
exacerbating agricultural challenges in drought-prone areas. For example, high temperatures
in South Asian countries like India and Pakistan have significantly impacted yields of staple
crops such as wheat and rice.
3.Increase in Extreme Weather Events
Climate change has intensified the frequency and severity of extreme weather events
such as hurricanes, floods, and heatwaves. These events not only directly destroy farmland
and infrastructure but also undermine agricultural productivity through soil erosion, saliniza-
tion, and the spread of pests and diseases. For instance, the 2020 locust plague in East Africa,
exacerbated by climate change-induced abnormal weather conditions, threatened food secu-
rity for millions.
4.Outbreak of Pests and Diseases
Climate change provides favorable conditions for the reproduction and spread of pests
and diseases. Rising temperatures and altered precipitation patterns shorten the survival cy-
cles of pests and accelerate their reproduction rates, thereby increasing the risk of crop dam-
age from pests and diseases. For example, pests such as corn borers and rice planthoppers are
more likely to proliferate in high-temperature and humid environments, leading to reduced
crop yields.
(2) Risks to Food Safety and Malnutrition
The negative impacts of climate change on agricultural production directly contribute to

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