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S. Ouda
agriculture is considered to be the most tangible affected sector, as any alteration
in the prevailing temperature or precipitation patterns will disturb the agricultural
sector as a whole, including crop yields, crops water requirements, and soil fertility
[4]. Climate change has already caused significant impacts on water resources and
food security [5]. Land ecosystems would require more water to match increased
water demand, and consequently to prevent drought [6]. Furthermore, it is expected
that competition between agriculture and other economic sectors will increase in the
future, which can reduce the allocation of water to agriculture. Reference and crop
evapotranspiration rates are likely to increase, as well as irrigation requirements for
the cultivated crops under climate change conditions [7] due to higher temperature,
solar radiation and wind speed [8]. It was reported that climate change is expected to
negatively affect crops productivity [9] and cause increases in water requirements for
crops in Egypt [10]. Thus, it is essential to improve water management in agriculture
and reduce unnecessary losses in the present time, adapt this behavior and carry it
with us for our future generations.
Despite technological advances in crops production, such as improved crop cultivars and irrigation systems, weather and climate are still key factors in agriculture
productivity. Evapotranspiration (ETo) is the key factor in determining crop water
requirements in various development stages. ETo is the combination of soil evaporation and crop transpiration [11]. Efficient water management of crops requires
accurate irrigation scheduling which, in turn, requires accurate measurement of crop
water requirement. Because climatic parameters are the only factors affecting ETo,
it is the most important hydrological and meteorological variable to reflect climate
change [12]. Previous research in Egypt on the effect of climate change on ETo values revealed that temperature rise by 1 °C might increase ETo rate by about 4–5%,
whereas a rise by 3 °C may increase ETo rate by about 15% [13]. Attaher et al. [14]
and Khalil [15] concluded that the future climate change in 2100 would increase
potential irrigation demands, due to the increase in ETo. Ouda et al. [16] stated that
the value of ETo would increase by an average of 9% in 2030 and by 13% in 2040
in Egypt.
Crop evapotranspiration (ETc) and crop coefficient (Kc) are two important factors
for crop production. Crop type, stage of growth, soil moisture, health of plants,
cultural practices are affecting both ETc and Kc [17]. Several studies were done
in Egypt to project the expected increase in water requirements for several crops
under climate change conditions [18–20, 16, 21–23]. Their results proved that water
requirements for crops would increase with different percentages depending on crop
type, growing season and geographic location.
On the other hand, Kc is a key component in ETc determination on the field level.
The variation and magnitude of Kc are important for the accurate determination of
ETc. Thus, the most known and used technique to estimate ETc is the one based on
the Kc approach [24] where the ETc is calculated using standard agro-meteorological
variables and a crop-specific coefficient, which should take into account the relationship between atmosphere, crop physiology and agricultural practices [25]. Although
several studies discussed the role of Kc in crops water requirements calculations [26,
27, 25, 28], few international studies dealt with the projected effect of climate change
S. Ouda
agriculture is considered to be the most tangible affected sector, as any alteration
in the prevailing temperature or precipitation patterns will disturb the agricultural
sector as a whole, including crop yields, crops water requirements, and soil fertility
[4]. Climate change has already caused significant impacts on water resources and
food security [5]. Land ecosystems would require more water to match increased
water demand, and consequently to prevent drought [6]. Furthermore, it is expected
that competition between agriculture and other economic sectors will increase in the
future, which can reduce the allocation of water to agriculture. Reference and crop
evapotranspiration rates are likely to increase, as well as irrigation requirements for
the cultivated crops under climate change conditions [7] due to higher temperature,
solar radiation and wind speed [8]. It was reported that climate change is expected to
negatively affect crops productivity [9] and cause increases in water requirements for
crops in Egypt [10]. Thus, it is essential to improve water management in agriculture
and reduce unnecessary losses in the present time, adapt this behavior and carry it
with us for our future generations.
Despite technological advances in crops production, such as improved crop cultivars and irrigation systems, weather and climate are still key factors in agriculture
productivity. Evapotranspiration (ETo) is the key factor in determining crop water
requirements in various development stages. ETo is the combination of soil evaporation and crop transpiration [11]. Efficient water management of crops requires
accurate irrigation scheduling which, in turn, requires accurate measurement of crop
water requirement. Because climatic parameters are the only factors affecting ETo,
it is the most important hydrological and meteorological variable to reflect climate
change [12]. Previous research in Egypt on the effect of climate change on ETo values revealed that temperature rise by 1 °C might increase ETo rate by about 4–5%,
whereas a rise by 3 °C may increase ETo rate by about 15% [13]. Attaher et al. [14]
and Khalil [15] concluded that the future climate change in 2100 would increase
potential irrigation demands, due to the increase in ETo. Ouda et al. [16] stated that
the value of ETo would increase by an average of 9% in 2030 and by 13% in 2040
in Egypt.
Crop evapotranspiration (ETc) and crop coefficient (Kc) are two important factors
for crop production. Crop type, stage of growth, soil moisture, health of plants,
cultural practices are affecting both ETc and Kc [17]. Several studies were done
in Egypt to project the expected increase in water requirements for several crops
under climate change conditions [18–20, 16, 21–23]. Their results proved that water
requirements for crops would increase with different percentages depending on crop
type, growing season and geographic location.
On the other hand, Kc is a key component in ETc determination on the field level.
The variation and magnitude of Kc are important for the accurate determination of
ETc. Thus, the most known and used technique to estimate ETc is the one based on
the Kc approach [24] where the ETc is calculated using standard agro-meteorological
variables and a crop-specific coefficient, which should take into account the relationship between atmosphere, crop physiology and agricultural practices [25]. Although
several studies discussed the role of Kc in crops water requirements calculations [26,
27, 25, 28], few international studies dealt with the projected effect of climate change