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Chapter Three Impacts of Global Climate Change

tion issues, compromising irrigation water availability.
2.Increased Salinization
In arid and semi-arid regions, excessive extraction of groundwater for irrigation leads to
soil salt accumulation, reducing land productivity. Meanwhile, saltwater intrusion caused by
rising sea levels threatens freshwater resources in coastal lowlands.
Aging reservoirs and irrigation systems
Water infrastructure in many developing countries was built decades ago and struggles
to meet new challenges posed by climate change. Aging reservoirs and irrigation canals re-
quire substantial funding for maintenance and upgrades, increasing burdens on the agricul-
tural sector.
(4) Challenges to Food Security
Growing uncertainties in agricultural production directly threaten global food security.
According to data from the United Nations Food and Agriculture Organization (FAO), ap-
proximately 828 million people worldwide currently suffer from hunger, with most concen-
trated in developing countries. Climate change further exacerbates this issue:
【1】Price Volatility
Agricultural market prices are heavily influenced by supply-demand dynamics. Produc-
tion declines caused by extreme weather events often trigger sharp price increases, raising
food acquisition costs for impoverished populations.
【2】Malnutrition
In addition to insufficient quantity, climate change may also lead to reduced content of
certain nutrients, such as deficiencies in trace elements like zinc and iron, which affect hu-
man health, particularly the growth and development of children.
【3】Migration and Conflict
Food shortages and reduced agricultural income drive some farmers to migrate in search
of better livelihood opportunities, sometimes triggering social instability and conflicts, espe-
cially in resource-limited regions.

II. Challenges in Water Resource Management

Climate change causes unstable water resource supply, deterioration of water quality,
and necessitates adaptive modifications to water infrastructure.
（I）Instability in Water Resource Supply
Climate change has significantly altered global precipitation patterns, leaving some re-
gions facing more frequent and severe droughts, while others endure threats of extreme rain-
fall and flooding. Thisunevendistribution of water resources has placed immense pressure on
agricultural, industrial, and urban water supply:
【1】Increased Aridification
Horn of Africa, the Middle East, and the southwestern United States have frequently ex-
perienced severe droughts in recent years, leading to declining groundwater levels and river

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