Introductory Chapter: Climate Change and Climate-Smart Greenhouses

1. Introduction

World is, nowadays, facing one of its most pressing ecological challenges — climate change. This phenomenon is characterized by significant and enduring shifts in weather patterns. It is mainly attributed to anthropogenic activities that increase the emissions of greenhouse gases [1] such as CO₂, CH₄, N₂O, O₃, chlorofluorocarbons (CFCs), CCl₄ [2], and H₂O [3]. Probably, CO₂ is the most important heat-trapping greenhouse gas (GHG) [4]. These gases absorb outgoing thermal (infrared) radiation, which is emitted by the surface of the Earth [5] and trap it within the atmosphere [6], thus increases the temperature of Earth’s surface [7]. These gases also increase the temperature of troposphere while decreased stratosphere temperature [8]. In addition to GHGs, 5–15% of the organic carbon is found as aerosols that persist in the atmosphere for long time periods [9] and serve as cloud condensation nuclei (CCN) [10], which absorbs visible solar radiation (approximately 20% of total absorbed light) [11]. This is known by brown carbon, which are particulate matters containing chromophores that increase global warming threats [10]. The repercussions of climate change span a vast spectrum from altering weather patterns to impact human health and exacerbating disparities. This chapter delves into the intricate relationship between climate change and agriculture while spotlighting the innovative concept of climate-smart greenhouses as a promising solution.

2. Climate change: causes, impacts, and effects on human health

Climate change, a lasting alteration in weather patterns spanning decades to millions of years [6], results mainly from escalating greenhouse gas (GHG) emissions linked to activities such as fossil fuel combustion, deforestation, and industrial processes [12]. Carbon dioxide stands as the primary GHG from human activities [13], with methane and nitrous oxide trailing closely [14]. These gases trap heat in the Earth’s atmosphere, elevating average global temperatures by 1–2% [15, 16]. These GHGs hasten the Earth’s water cycle [8], leading to amplified evaporation from water surfaces [16], resulting in heightened drought frequency and intensity in various regions [17]. In contrast, other areas experience increased precipitation [16], leading to rising sea levels [12], expanding regional tides, and intensifying extreme events, such as hurricanes and floods [12]. Climate change exerts profound impacts on food and water supplies, human habitation, public health, and economic activities [18, 19]. The World Health Organization predicts that climate change may contribute to roughly 250,000 additional annual deaths by 2050, primarily due to malnutrition, malaria, diarrhea, and heat stress [20]. Vulnerable populations, including children, the elderly, low-income communities, and individuals with chronic illnesses, bear a disproportionate burden [19]. Heatwaves pose risks of heat exhaustion and heat stroke, exacerbating cardiovascular and respiratory diseases. Altered temperature and precipitation patterns also affect disease-carrying insects, increasing the transmission of illnesses, such as malaria and dengue fever [20]. Furthermore, climate change exerts adverse effects on mental health. The growing frequency and severity of extreme weather events and natural disasters contribute to post-traumatic stress disorder (PTSD), anxiety, depression, and other mental health issues [21]. Health disparities worsen with climate change, particularly impacting vulnerable populations with limited resources to adapt [22]. Addressing climate change necessitates a concerted global effort to reduce GHG emissions and adapt to ongoing changes [6].

3. The impact of climate change on agriculture

Climate change poses significant challenges to global agriculture and food security [12]. Rising temperatures, driven by the Industrial Revolution, have increased by 0.9°C since the nineteenth century and are projected to reach 2°C by 2100 [23, 24]. This warming can accelerate crop respiration and evapotranspiration [7], alter pest and disease distribution, and shorten the reproductive period in crops, such as wheat and rice [24, 25]. Wheat yields may decrease by 20–45%, and rice yields by 20–30% by 2100 [24]. Heat stress can cause post-heading carbon deficits in wheat [26]. Irregular precipitation patterns also impact agriculture [24], with some regions experiencing increased rainfall and others facing more frequent and severe droughts [7]. Both flooding and drought have adverse effects on crop yields, limiting growth, causing damage, and influencing the prevalence of pests and diseases [27, 28].

Climate change further challenges natural resource management in agriculture. Higher temperatures lead to increased evaporation rates, depleting water resources, and particularly affecting irrigation-dependent agriculture. Rising sea levels and increased salinity can degrade arable land, especially in coastal and delta regions [29]. To ensure agricultural sustainability in a changing climate, it is crucial to develop and implement adaptive strategies, including climate-resilient crop varieties, improved pest and disease management, and efficient water resource utilization [12].

4. Adaptation and mitigation strategies for climate change

Climate change presents significant challenges that require a comprehensive response. In 2015, an agreement was held in Paris to lessen the rise in global temperature by 2°C in 2100 [30]. Two primary strategies were adapted to attain this aim, which are adaptation and mitigation [31]. While mitigation focuses on reducing the causes of climate change, adaptation involves adjusting to its impacts [12]. Adaptation, therefore, is essential to manage unavoidable impacts, while mitigation is needed to limit the long-term changes in climate. The optimal mix of adaptation and mitigation measures will depend on local and regional factors, including climate change impacts, economic structures, and societal values.

5. Adaptation

Adaptation strategies mitigate global warming impacts [32] for future food security [33]. They involve altering processes, practices, and structures to reduce potential damage and capitalize on climate change opportunities [34]. Adaptation spans individual actions to institutional policies and includes financial adjustments [35]. In agriculture, strategies encompass crop enhancements, food waste reduction [33], water conservation policies [36], adjusted planting schedules to avoid extreme weather, and adopting resilient crop varieties [37]. Biodiversity enhancement can also aid climate mitigation [38]. Organic extracts, such as humic and fulvic acids or compost tea, promote plant growth, sequestering more CO₂ in plant tissues [39, 40, 41]. In the health sector, adaptation focuses on enhancing public health infrastructure to manage heatwaves and disease outbreaks, incorporating early warning systems, and improving air and water quality [42]. Urban areas should adapt by bolstering infrastructure resilience, implementing heat-wave action plans, creating cooling urban green spaces, and efficient water resource management [43].

Despite adaptation’s importance in mitigating global warming’s negative effects, maladaptation can occur [44]:

1. Infrastructural Maladaptation: For instance, sea walls in Fiji designed to combat rising sea levels hindered stormwater drainage. In Bangladesh, flood control measures reduced soil fertility and livelihood security.

2. Institutional Maladaptation: Farmers alter land use planning by growing cash crops, intercropping, and adopting moisture conservation techniques to address climate risks.

3. Behavioral Maladaptation: In northern Ghana, farmers migrate in search of employment, causing labor shortages.

6. Mitigation

Mitigation involves strategies to lessen or even stabilize emission of greenhouse gases in the atmosphere via adopting three strategies mentioned by Fawzy et al. [30] which are:

1. Switch to clean energy (renewable energy and nuclear power) or low carbon fuel to generate electricity and get heat rather than the burning of fossil fuels (conventional mitigation efforts). According to this approach, emissions of GHGs should be reduced by 45% in 2030 versus their levels in 2010 levels then reach finally to net-zero emissions by 2050.

2. Increasing the capability of sinks (oceans, soil, and forests) to capture and sequester GHGs gases (negative emissions technology).

3. Applying new techniques to managing solar and terrestrial radiation such as “stratospheric aerosol injection, marine sky brightening, cirrus cloud thinning, space-based mirrors and surface-based”; yet these methods are still theoretical.

Probably, energy production is the major source of greenhouse gas emissions, so applying new technologies to improve energy efficiency in buildings, transportations, and industrial processes might reduce effectively GHGs emissions [45]. In the agricultural sector, mitigation strategies include improving crop and livestock management practices to reduce methane and nitrous oxide emissions, protecting and restoring forests to sequester carbon, and managing soils to increase their carbon storage capacity [46, 47].

7. Climate-smart greenhouses: a sustainable approach to agriculture

The global agricultural sector faces climate change challenges, impacting crop yields and food security [12]. Climate-smart greenhouses, part of controlled environment agriculture (CEA), use advanced technologies to optimize plant growth and reduce environmental impact. They prioritize increasing productivity, adapting to climate change, and minimizing emissions [48, 49]. These greenhouses employ precision irrigation to conserve water and ensure ideal moisture levels, automated climate control to optimize growth and energy use, and energy-efficient lighting, such as LED, with minimal energy and water consumption [50, 51, 52]. Integrated pest management reduces reliance on chemical pesticides, benefiting crop health and sustainability [48].

Renewable energy sources, such as solar and wind power, further reduce environmental impact, and water conservation practices are employed [48]. Climate-smart greenhouses offer a promising solution to climate-related agricultural challenges, integrating technology and sustainable practices for increased productivity and reduced environmental impact [49].

8. Design and structure

Climate-smart greenhouses are designed to optimize the use of natural resources and energy. Sensors and devices (Internet of Things, IOT) can be used to monitor precisely, and then efficiently control all indoor parameters [52]. Greenhouses are often constructed with materials that maximize light transmission while provide insulation to reduce energy use for heating or cooling. Their structure and orientation allow maximizing natural light and regulating temperature [48]. Roofs and/or sides may be covered by an impermeable transparent plastic film to allow natural ventilation [53]. Android mobile applications are sometimes used to monitor and send warning messages about the state of plants.

9. Climate control systems

One of the key features of climate-smart greenhouses is to lessen energy consumption while increasing plant productivity [54]. This may take place via applying automated climate control systems that use different sensors to collect data continuously [50] and then use mathematical models for calculating solar irradiation, photosynthesis, and evapotranspiration [55]. These schemes can, therefore, regulate temperature, humidity, and light levels to create optimal growing conditions needed for plants at each growth stage to get high-yield production [56]. Ventilation and shading can also be adjusted to control the internal climate and reduce the need for artificial heating or cooling. In tropical and subtropical climates, covering materials are used for shading and cooling in greenhouses [56]. Some systems even include CO2 enrichment to enhance plant growth [48].

10. Water and nutrient management

Climate-smart greenhouses often incorporate precision irrigation and fertigation (fertilizer + irrigation) systems [57] using a combination of sensors and nutrient delivery schemes [58]. These systems deliver water and nutrients directly to the plant roots, reducing wastes, and ensuring that plants receive the optimal amount of moisture and nutrients. Some greenhouses also capture and reuse water through rainwater harvesting or condensation capture systems, contributing to water conservation efforts [48]. The emission of N gases from high-tech greenhouses that follow efficient recirculation systems is thought to be very low [59].

11. Energy efficiency and renewable energy

Energy efficiency is the key aspect of climate-smart greenhouses. Many climate-smart greenhouses use renewable energy sources, such as solar or wind power [48]. Using photovoltaic-thermal collectors of solar energy can produce both heat and electricity, with less shading [60]. Also, using energy-efficient lighting, such as LED lights, provides specific light spectrum needed for photosynthesis while using less electricity (40%) than traditional lighting systems and also less heat (9–49%) [61]. In cold regions, minimizing heating cost is another challenge. Thus, isolating greenhouses and/or using geothermal energy may help to lessen these costs [62].

12. Integrated pest management

Climate-smart greenhouses often use integrated pest management strategies to reduce the need for chemical pesticides. These strategies include the use of beneficial insects to control pests, use of physical barriers or traps, and the careful monitoring of pest populations to determine when control measures are needed [63, 64]. Microbial pesticides can also be used if natural enemies are not sufficient for pest control [65]. Moreover, solar ultraviolet-B lamps can provide a physical control for spider mites [66]. Climate-smart greenhouses represent a promising solution to the challenges posed by climate change in the agricultural sector. By integrating advanced technologies and sustainable practices, these greenhouses increase agricultural productivity, adapt to changing climate conditions, and reduce environmental impacts.

13. The role of greenhouse cultivation in climate change mitigation

Greenhouse cultivation, particularly when implemented with climate-smart practices, can play significant roles in mitigating climate change. This can be achieved via applying more efficient techniques in resource management, reducing wastes, and carbon sequestration. Generally, there are two methods to control greenhouse conditions (i) a passive method that depends on a natural phenomenon “hot air rises and cold air sinks,” so it requires minimum energy while (ii) the active method needs fans for and heaters to control the environment inside greenhouses [67]. By means of thermal energy storage (TES) systems, heat can be successfully stabilized within greenhouses for plants [68]. These systems analyze the complex thermal processes within this indoor microclimate area and contribute toward efficient usage of this energy [69]. On the other hand, CO2 enrichment environment inside greenhouses can boost plant growth by approximately 35% [69, 70] via sequestrating CO2 from ambient air rather than being emitted to the atmosphere to increase the emissions of GHGs [71].

14. Efficient use of resources

Managing agricultural resources to meet rising food demands due to population growth is crucial [69], but natural resource limitations challenge food production [72]. Agricultural activities also contribute significantly to greenhouse gas (GHG) emissions [68], emphasizing the need for ecological considerations. Controlled environment agriculture (CEA), such as greenhouses, offers year-round food production possibilities [67]. Utilizing intelligent shading systems, smart glass, sensors, IoT, and AI [68], greenhouses precisely control conditions such as temperature, light, and humidity [73], increasing yield per unit area compared to traditional methods and conserving water through precision irrigation [48]. Some greenhouses capture and reuse water, further reducing water use [48]. Bioagents in greenhouses enhance horticultural yields and environmentally friendly pest and disease control, reducing GHG emissions related to agrochemicals [64, 74]. Greenhouses, by growing crops near consumption points, reduce transportation-related carbon emissions, especially in urban agriculture [75].

15. Carbon sequestration

Greenhouse gases can be reduced via a process known by phytosequestration [6]. In this method, plants absorb carbon dioxide gas from the atmosphere, change it to organic forms via Calvin cycle then sequester large amounts of C in their biomasses [76]. Herbaceous plants, which have relatively low planting-environment requirements, exhibit more capability to sequester C in their tissues than woody plants[77]. Surprisingly, sequestration of CO2 by microalgae is deemed as a net zero GHG emissions [78]. On the other hand, amounts of carbon sequestered via this process are relatively slow versus CO2 release due to anthropogenic activities [79]. Also, this process lasts for relatively short time periods because when plants decay and sequestered C returns back to air [6]. Weighing up pros and cons of phytosequestration, reforesting, and managing ecosystems are still effective ways to mitigate the global warming threat [79].

16. Reduced waste and emissions

The terrestrial carbon pool is four times larger than the atmospheric carbon pool [4]. Recycling agricultural waste can significantly reduce greenhouse gas emissions, with over 5.6 billion mega grams of carbon potentially sequestered from the 18 billion wasted annually worldwide [80]. This can be achieved by converting organic residues into biochar, produced under limited oxygen conditions [81, 82, 83, 84, 85, 86]. Biochar reduces easily oxidized carbon content, decreasing microbial metabolic activity by 47% [87], leading to longer soil retention when used as a soil amendment [88, 89, 90] or organic fertilizer [91, 92]. Its porous structure enhances soil CO2 adsorption via physisorption and chemisorption [93], sequestering carbon instead of releasing it into the atmosphere [87]. Scientists have devised a method to capture smoke emissions during biochar pyrolysis, using them for soil injection to improve seed germination and potentially achieve net-zero greenhouse gas emissions [94, 95]. Using biochar as a soil amendment can reduce CO2 emissions by about 1/8 [95], while converting residues to charcoal may cut GHG emissions by 80% within 8.5 years [96]. The potential for carbon sequestration in greenhouses remains an ongoing research topic, with outcomes depending on various factors, including greenhouse type, crop varieties, and management practice.

In conclusion, climate-smart greenhouse can contribute to climate change mitigation through more efficient use of resources, reduced waste and emissions, and potentially through carbon sequestration. However, it is important to note that not all greenhouses are the same, and the climate impact will depend on the specific design and management practices used.