Page 254 - Çevre Şehir ve İklim Dergisi İngilizce - Özel Sayı

Footprints of the Nature in Cities; Urban Heat Island Effects
and the Role of Afforestation Efforts in Reduction of These Effects

Table 2: The Effects of Urban Heat Island on Water Resources

The demand for water increases along with the increasing temperatures
of the urban heat island. Especially during the summer months, when
Increased Water
Consumption temperatures rise excessively, the use of cooling systems, landscape
irrigation, and personal water consumption increase. This situation in-
creases pressure on regional water resources (Oke, 1982) In arid regions,
this effect can lead water resources to decline more rapidly.

The urban heat island can alter local climate characteristics, affecting
precipitation patterns. Rising temperatures accelerate evaporation,
Rainfall and leading to disruptions in the water cycle. It can also lead to more intense
Water Cycle rainfall in urban areas. Intense rainfall can lead to sudden flood events
and cause damage to urban infrastructure (Grimmond, 2007). This pro-
cess makes it more difficult to manage water resources effectively.

High temperatures in urban areas can cause surface waters to warm up.
Since warm water has a reduced capacity to hold oxygen, ecosystem
The Negative
Impacts on Water disturbances can be observed in surface water sources such as rivers and
lakes. High temperatures also increase water pollution by negatively af-
Quality
fecting water quality (Kaushal et al., 2010). (24) Additionally, temperature
increase can lead to algal blooms in water sources.

Rising temperatures, combined with the urban heat island effect, place
Pressure on additional strain on water distribution infrastructure in cities. Especially
Infrastructure old pipe systems may be damaged due to expansion and contraction,
leading to water leaks and losses (Rosenfeld et al., 1995). Additionally,
high temperatures can increase the rate of evaporation, causing water
reserves to deplete more quickly.

UHE raises temperatures within cities, accelerating evaporation, which can
lead to the drying up of surface waters and a decline in lake and river levels.
Increased temperatures also affect the natural water cycle, raising water
temperature and reducing water quality. The increase in water temperature,
especially in ponds and rivers within cities, reduces oxygen levels, making it
more difficult for plant and animal species in aquatic ecosystems to survive.
The UHE effect increases water consumption and dependence on cooling
systems like air conditioners in cities, thereby raising the demand for water
resources. This can threaten urban water security, particularly during dry
periods. For these reasons, managing the impact of UHE on water resources is
crucial for a sustainable water policy and the long-term water security of cities.

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