Status of Solar-Energy Adoption in GCC, Yemen, Iraq, and Jordan: Challenges and Carbon-Footprint Analysis

: This work examines the potential of some of the Gulf Cooperation Council countries (GCC) (Saudi Arabia (KSA), the United Arab Emirates (UAE), Qatar (QA), Bahrain (BH), Oman (OM)), Yemen (YE), Iraq (IQ), and Jordan (JO) to use their abundant solar radiation to generate electricity through PV technology. The study is structured to help decision-makers access the necessary data related to the status of solar-energy infrastructure and power production in the study region. The study investigates current efforts to establish PV technology and the challenges hindering the development of this technology. These efforts and challenges are then benchmarked against their status in Australia, which has climate and landscape conditions similar to those of the countries in the study region. It was found that Australia is successfully adopting solar energy in households and industrial locations despite its historical reliance on fossil fuels for energy production. This offers a potential avenue for replicating the Australian model of PV development in the study region. This work also addresses the effect of natural and anthropogenic aerosols on the performance of the PV panels. Meanwhile, it also proposes a conceptual model to help local governments and decision-makers in adopting solar-energy projects in the study region. Additionally, a preliminary carbon-footprint analysis of avoided emissions from PV energy utilization compared to national grid intensity was performed for each country. Findings show that the countries in the study region have great potential for using solar energy to gradually replace fossil fuels and protect the environment. It is observed that more hours of daylight and clear-to-scattered cloud coverage help increase solar irradiance near the ground all year around. Dust and aerosol loadings, however, were found to greatly reduce solar irradiance over the GCC area, especially during large dust events. Despite the high potential for harvesting solar energy in the study region, only a handful of PV plants and infrastructural facilities have been established, mostly in the KSA, the UAE, and Jordan. It was found that there is a critical need to put in place regulations, policies, and near-future vision to support solar energy generation and reduce reliance on fossil fuels for electricity production.


Introduction
Since the establishment of the petroleum industry in 1875, fossil fuels became one of the major energy sources worldwide [1]; however, the burning of fossil fuels generates air pollutants like particulate matter, sulfur, and nitrogen oxides, which can cause a number of health impacts, including lung and heart diseases [2,3].Greenhouse gases associated with fossil-fuel burning store heat in the Earth's atmosphere and increase Earth's temperature [4].Moreover, extracting fossil fuels can cause water pollution and soil erosion [5].Additionally, fossil-fuel sources are finite [6] and globally depleting at an alarming rate.Such concerns have increased demand for alternative energy resources, such that industrial and scientific entities are investing substantial work in developing new technologies to harvest renewable energy [7][8][9] that comes directly or indirectly from the Sun.
Solar energy is sustainable, easily accessible, and environmentally friendly compared to traditional fossil-fuel energy sources.Solar energy is one of the best options to generate electricity, particularly for countries that lack fossil-fuel sources or other renewable energy sources like hydropower and wind sources.Solar energy could also be an option for the oil-rich countries who want to reduce their dependence on non-renewable fossil fuels and reduce greenhouse-gases emissions.
Solar panels are devices that use photovoltaic (PV) cells to convert solar energy into electricity [10,11].Improvements in solar panels' durability and efficiency and reductions in their development cost helped in the establishment of large PV solar panels in many countries across the world [12,13].For example, in recent years, the United States of America has experienced large growth (~42% annually) in solar-energy production, with solar plants producing over 100 GW in 2021 [14], enough to power over 18 M houses.Meanwhile, over the last decade, the United Kingdom has experienced a growth of ~35% annually in solar-energy generation, with solar plants producing over 14 GW in 2021, enough to power over 2.5 M houses [15].Meanwhile, due to its vast land area and plentiful sunshine, South Africa [16] has high potential for solar-energy production.The largest solar-energy plant in South Africa, which is located in the Kathu Solar Park, has a capacity of ~100 MW, and the total installed capacity of solar-energy production across the country is ~2.4GW as of 2021 [17,18].
Rapid economic development and population growth in the oil-rich Gulf Cooperation Council (GCC) countries [19,20] (Saudi Arabia-KSA, United Arab Emirates-UAE, Qatar-QA, Bahrain-BH, Kuwait-KW, and Oman-OM) (Figure 1) have significantly increased energy demands over the last few decades.The GCC countries consume approximately 20% of the world's oil production and are among the major consumers of natural gas [21,22].Moreover, air conditioning and water-desalination plants add to the energy demands in GCC [23,24].
Despite their slower economic growth compared to GCC, Yemen, Iraq, and Jordan (Figure 1) have also high energy demands, and the majority of their energy consumption is in transportation and electricity generation [25].Most of these countries are heavily dependent on fossil fuels to cover their energy needs.This high energy demands have created a surge in interest in diversifying their energy sources and exploring renewable energy as an additional source for power generation [26].
The selected countries in this work are located within the Sun Belt region (40 • S to 40 • N) and are known for their arid/semiarid landscape and abundance of sunshine most of the year, which make them potential candidates for harvesting solar energy.However, a better understanding of the temporal and spatial characteristics of solar energy and better knowledge of the existing capacity of the current PV networks is important to optimizing the use of solar energy in this part of the world [27,28].
These countries are, however, heavily dependent on fossil fuels to secure their energy needs.The GCC region hosts six oil-and natural-gas-rich countries; the KSA and the UAE rank among the world's top oil producers, while Qatar is one of the world's top natural-gas producers.This increased the GCC reliance on fossil fuels and reduced the investments on alternative energy resources.Meanwhile, Yemen, Iraq, and Jordan also rely on fossil fuels as their main source of energy, as there are no alternative energy supplies.PV technology could provide the region with an alternative supply of clean energy that can reduce their high reliance on fossil fuels.Despite their slower economic growth compared to GCC, Yemen, Iraq, and Jordan (Figure 1) have also high energy demands, and the majority of their energy consumption is in transportation and electricity generation [25].Most of these countries are heavily dependent on fossil fuels to cover their energy needs.This high energy demands have created a surge in interest in diversifying their energy sources and exploring renewable energy as an additional source for power generation [26].
The selected countries in this work are located within the Sun Belt region (40 °S to 40 °N) and are known for their arid/semiarid landscape and abundance of sunshine most of the year, which make them potential candidates for harvesting solar energy.However, a better understanding of the temporal and spatial characteristics of solar energy and better knowledge of the existing capacity of the current PV networks is important to optimizing the use of solar energy in this part of the world [27,28].
These countries are, however, heavily dependent on fossil fuels to secure their energy needs.The GCC region hosts six oil-and natural-gas-rich countries; the KSA and the UAE rank among the world's top oil producers, while Qatar is one of the world's top naturalgas producers.This increased the GCC reliance on fossil fuels and reduced the investments on alternative energy resources.Meanwhile, Yemen, Iraq, and Jordan also rely on fossil fuels as their main source of energy, as there are no alternative energy supplies.PV technology could provide the region with an alternative supply of clean energy that can reduce their high reliance on fossil fuels.
The aim of this work is to investigate the potential of the GCC countries, Yemen, Iraq, and Jordan to adopt solar energy in their electricity-generation networks.This article tries to shed light on the potential of this region to become one of the major global areas harvesting solar energy.This is done through the collection of meteorological and solar-radiation data in the mentioned countries.These data concern meteorological conditions, cloud coverage, and sunshine duration all year round and cover the period from 1985 to 2015 (based on data availability); further, we conducted an investigation of the possible effects of local weather on PV efficiency.Finally, satellite data were used to elucidate aerosol and dust loading in the study area and their possible effect on scattering and absorbing solar radiation.Section 1 is an introduction to the study area, the research gap, and Longitude, ºE Latitude, ºN The aim of this work is to investigate the potential of the GCC countries, Yemen, Iraq, and Jordan to adopt solar energy in their electricity-generation networks.This article tries to shed light on the potential of this region to become one of the major global areas harvesting solar energy.This is done through the collection of meteorological and solar-radiation data in the mentioned countries.These data concern meteorological conditions, cloud coverage, and sunshine duration all year round and cover the period from 1985 to 2015 (based on data availability); further, we conducted an investigation of the possible effects of local weather on PV efficiency.Finally, satellite data were used to elucidate aerosol and dust loading in the study area and their possible effect on scattering and absorbing solar radiation.Section 1 is an introduction to the study area, the research gap, and the goal of the current study; Section 2 describes the methodology of the study; Section 3 reports recent advances in solar PV development and solar-energy research in each country of the study region; Section 4 highlights the results of the current study; and Section 5 includes the discussions.
This information can help local governments and decision-makers to decide the capacities and locations of new PV plants to maximize harvesting of solar energy in the study region [29].

Materials and Methods
The status of the current solar PV infrastructure in the GCC countries, Yemen, Iraq, and Jordan was investigated using databases, governmental websites, public and private sector reports, books, conference proceedings, peer-reviewed journals, and other related sources.
Dust and aerosol data were collected using the Moderate Resolution Imaging Spectroradiometer (MODIS) on the Giovanni NASA platform [30].MODIS is a key sensor instrument aboard the Terra and Aqua satellites that collects data over the entire globe every 1-2 days.Since the beginning of the Terra satellite mission in 2000, MODIS has provided data on aerosol loading over land and water at 3 km resolution [31,32].The aerosol optical depth (AOD) is a dimensionless optical parameter that can be retrieved by MODIS and designed to measure the extinction of the solar radiation by aerosols, haze, and dust.
AOD uncertainty is ±0.05 (±0.2 × AOD) over land and ±0.03 (±0.05 × AOD) over water.MODIS collects spectral data over the entire globe in 36 spectral bands in the visible, near infrared, and shortwave infrared parts of the electromagnetic spectrum.Furthermore, MODIS also collects data in the thermal portion of the spectrum.Over vegetated regions, MODIS collects AOD 550 data in three visible channels (0.47, 0.55, and 0.66 mm) with ±0.05 accuracy and also calculates surface reflectance over land at IR (0.7-5.0 µm) and visible (0.3-0.7 µm).MODIS Deep Blue product is used over the desert areas at (2.1 to 3.8 µm).The most recent 3 km high-resolution Level-3 data from the MODIS Collection 6 dataset release are used in this study [31].
Average monthly and daily solar irradiation and PV output data were extracted and analyzed using the map-based Global Solar Atlas [33].
Data from the International Energy Agency (IEA) were used to calculate carbonemission saving using the electric power capacity generated by the PV panels from 2000 to 2021 in each country of the studied region using the following equation: where CO 2 (es) is the CO 2 emission savings in Mt (Mega tons); CO 2 (e) is the CO 2 emissions from oil and natural gas (Mt/GWh); and PV(Eg) is the electric energy generated by solar PV panels (GWh).
The effect of aerosols and dust storms on reducing the efficiency of solar panels is discussed.Meanwhile the successful Australian model for the adoption of solar energy is then investigated to examine how countries in the study area can learn from that model to make using PV panels more popular.

Results
Tables 1-3 displays the geographical coordinates and average meteorological conditions in Saudi Arabia, the UAE, Qatar, Bahrain, Oman, Yemen, Iraq, and Jordan during 1985-2015.The existing climatological conditions, including low cloudiness and long daylight hours, provide a great advantage in using solar energy as an alternative to conven-

Results
Tables 1-3 displays the geographical coordinates and average meteorological conditions in Saudi Arabia, the UAE, Qatar, Bahrain, Oman, Yemen, Iraq, and Jordan during 1985-2015.The existing climatological conditions, including low cloudiness and long daylight hours, provide a great advantage in using solar energy as an alternative to conventional fossil-fuel energy sources.Solar power plants are, however, relatively new in the study area.Frequent dust storms from vast deserts located in those countries make it difficult to maintain solar panels; they also reduce PV's efficiency.Some countries, like Yemen and Jordan, have to rely on foreign investments to establish large solar power stations, with the KSA and the UAE among the key players in such investments [34][35][36].Several studies have examined various aspects of solar radiation and production of electrical power using solar energy and identified the optimum localities to obtain maximum power from PV networks.A model was developed in [37][38][39][40][41], and its results were compared with those from 16 other models in different regions with different meteorological conditions.The results of the study show that the model provides reliable estimates of solar radiation over the KSA.The optimum inclination angles for different PV operations are discussed in [42,43].
Similarly, radiation resources in Saudi Arabia have been examined [39,40,44].The findings sjow that the western regions of the country are more suitable relative to the eastern ones for electric power production through solar energy.The mean daily total solar energy in the western part was 6474 Wh/m 2 , while the eastern regions attained an average daily total around 5510 Wh/m 2 .Moreover, a mathematical model was used in [45] to simulate the hourly solar-radiation data for four different climatic regions (i.e., Jeddah, warm and humid; Dhahran, maritime and inland desert; Riyadh, hot and dry; Taif, highlands).The results showed a model uncertainty of less than 10%.
[46] discussed the solar-radiation atlas of Saudi Arabia.Based on the atlas, the direct normal solar irradiance in different areas of Saudi Arabia varies from 9000 W h/m 2 /day to 5000 W h/m 2 /day during the months of June-August and January-March, respectively.Subsequently, Ref. [47] estimated the global and solar radiations on horizontal and tilted surfaces over Jeddah using different meteorological parameters (i.e., temperature (max and min), daylight hours, and cloud cover) for the period 1996-2007.An empirical relationship was then examined for diffuse solar radiation on horizontal surfaces, while the total solar radiation on tilted surfaces was estimated by using [48] "isotropic" and [49] "anisotropic" models and compared them with the results of the NASA "SSE model".The findings highlight that these models are capable of estimating solar radiation on horizontal and tilted surfaces in Jeddah with a reasonable precision.A simple model was developed in [50] to estimate the monthly average global solar radiation over Tabouk and compared the model output with those from 29 other regression models and with collected solar-radiation data.The results showed high precision for the region.The optimum tilt angle for PV solar panels was also estimated for the city of Najran in the southwestern region of Saudi Arabia [51].
Saudi Arabia adopted a national renewable-energy program called "Saudi Vision 2030" [52] to maximize the potential of renewable energy in the country.The strategy sets out plans to stimulate the kingdom's economy through a diversity of local energy sources, which include establishing PV power plants that can support the promising industrial sector in the country and reduce greenhouse-gas emissions [53].Table 1 displays the major PV plants established in Saudi Arabia.

United Arab Emirates
The average solar radiation on the horizontal plane over Abu Dhabi city, UAE, was investigated [7] by utilizing sunshine-duration data.The investigation revealed that the "Angstrom-Prescott model" and the "third-order model" efficiently predict solar radiation on the horizontal plane.Similarly, Ref. [8] predicted the solar radiation based on various parameters such as maximum temperature, mean wind speed, mean relative humidity, and sunshine duration.The results showed that an artificial neural network (ANN) model is the most suitable model by which to predict the solar radiation over the UAE.Solar radiation was mapped [9] by using the advanced ANN ensemble technique, and the findings showed that the performance of ANN is quite good compared to previously employed techniques in predicting solar radiation over the region.Further, Ref. [54] evaluated the Global Horizontal Irradiance (GHI) by using the ANN method at Abu Dhabi.
The UAE is one of the world's largest oil producers; however, the country took several steps towards implementing solar power on a large scale.Solar power plants are rapidly developed [55].The state of Dubai aims to provide 25% of its energy needs from renewable resources by 2030.Table 1 names the major solar plants in the UAE [56].
The Radial Basis Function (RBF) and Multi-layer Perceptron (MLP) algorithms, as learned by an ANN model, were utilized to evaluate solar radiation for the time spans 1993-2003 and 2004-2008.Subsequently, Ref. [57] adopted a machine-learning technique to predict solar radiation over the UAE.The researchers employed two types of machinelearning models, i.e., the support-vector regression and the recurrent neural network.
Nevertheless, the key findings suggested that a combination of both models' prediction is good compared to individual models alone.Solar radiation, along with other meteorological parameters such as relative humidity, ambient-shaded temperature, and pressure, were investigated at Ras Al-Khaimah during the period 2013-2015 [58].The results confirmed the high levels of solar radiation received between April and August.However, high temperatures negatively impact the solar energy system's efficiency.In another study, Ref. [59] explored the use of a dynamic recurrent neural network (DRNN) and showed its good performance compared to simple multi-layer perceptron (MLP) to predict GHI.In addition, Ref. [63] estimated the downwelling solar irradiance for clear-sky conditions using the McClear model and validated the model relative to an AERONET dataset over the UAE.Furthermore, Ref. [64] evaluated Direct Normal Irradiation (DNI) in Abu Dhabi and compared it along with other meteorological parameters using the NASA SSE model.The comparison showed good agreement between DNI, meteorological parameters, and the NASA SSE model.The daily mean solar radiation was predicted in the Al Ain region using a time-series regression model [65].The findings affirmed that the time-series regression model is a suitable way to predict GHI over the region.Moreover, Ref. [66] calculated the global solar horizontal radiation for Dubai and Sharjah and compared these values with those derived by the NASA SSE model.

Qatar
Various studies have been conducted to explore the solar potential of and power generation in Qatar.One study [67] discussed the potential long-term solar resources and power generation in Qatar.The results showed that large-scale thermal storage and gridconnected PV systems provide a reliable solution to inter-annual variability and long-term stability for electricity generation.DNI, GHI, and Direct Horizontal Irradiation (DHI) were measured in [67] using data from the monitoring station at Doha (Qatar) for a six-month period (December 2012-May 2013).The findings revealed that maximum monthly averages were obtained in Feb (DNI), May (GHI), and April (DHI), while high daily averages were found in May for all parameters.Furthermore, Ref. [68] mapped the annual GHI over Qatar during the period 2007-2012.These maps were based on the data from 12 groundbased stations; the results showed a measured annual average solar potential for Qatar of 2113 kWh/m 2 .Similarly, Ref. [69] investigated the feasibility of PV power generation in Qatar and compared its operational cost with that of a conventional gas-turbine system.The results highlighted that PV stations are not economically feasible compared to gasturbine stations.Moreover, Ref. [70] estimated the global horizontal solar radiation and sunshine duration over Doha; the results revealed that the region is blessed with abundant solar potential.
The variability of global horizontal irradiance over Qatar was assessed in [40].The findings showed high variability of GHI in the southern and northern regions of Qatar, while low GHI existed in the central regions.Consequently, Ref. [71] created a dynamic atlas for the solar resources of Qatar that shows solar irradiation throughout the region every 15 min.This dynamic atlas also highlights the solar resources for power generation.
Qatar is the world's second-largest exporter of natural gas, as it owns the world's third-largest natural-gas reserve [72].This has made the country less reliant on renewable energy sources for many years; however, in 2020, Qatar started to develop the Al Kharasaah solar-power project (Table 1), which is located about 80 km west of the capital of Doha.The project started to operate in 2022 with a power production capacity of 80 MW.The Al Kharasaah project is using end-of-line sun-tracking and robotic cleaning of solar panels to increase the efficiency of solar production.

Bahrain
There have been numerous efforts in the past to estimate the solar potential for the development of solar energy in Bahrain.For example, Ref. [73] employed an empirical correlation technique to estimate the monthly mean daily solar radiation on horizontal surfaces via meteorological parameters such as sunshine duration, maximum temperature, relative humidity, mean sea-level pressure, and vapor pressure over Bahrain.The findings showed good agreement between the estimated and measured values for monthly average solar radiation.
Similarly, Ref. [74] developed an empirical model to estimate the hourly solar radiation for Bahrain.The comparison of the developed model with findings from other studies showed a reasonably good consensus for the region.Moreover, Ref. [75] modified the Gopinathan model for better estimation of solar radiation on horizontal surfaces in the Bahrain region.In addition, Ref. [76] determined the monthly average daily solar radiation for Bahrain using the Ångström correlation method.It was revealed that different astronomical and meteorological parameters greatly affect estimates of solar radiation over the region.Further, Ref. [77] estimated the monthly mean daily total, diffuse, and direct normal solar radiation on horizontal surfaces over Bahrain using simple models.However, the results found that the estimated GHI at four different places in Bahrain is closer to the measured values, falling within the range 820-1000 W/m 2 .
Bahrain also receives some of the highest levels of sun radiation in the world (2180 kWh/m 2 ) [78]; the country thus has some ambitious plans to generate 700 MW from renewable energy resources by the end of 2030 [79].The major solar power plant currently operating in Bahrain is included in Table 1.

Oman
For Oman, there are few studies available that highlight solar potential for electricity generation.One of the studies [80] discussed the prospects for solar-power generation in Oman, and the results revealed that the country has vast solar potential and could generate up to 7.6 million GWh of power yearly power, which is 680 times more than the current power generation.Moreover, Ref. [81] modelled DNI, DHIl, and GHI on horizontal and inclined surfaces.The results showed good agreement with the measured data from different sources.
Monthly mean global solar radiation over Oman was evaluated through daily measurements in [82] for the period of six years.The global solar components such as direct, diffuse, and global irradiance were also calculated by employing empirical models and utilizing meteorological data from six stations.Similarly, Ref. [83] investigated the climate data (ambient temperature, wind speed, relative humidity, solar radiation, and sunshine duration) over Oman that were directly involved in the development of the models.The findings highlighted the existing general weather patterns over the region, along with the similarities and dissimilarities among various weather stations.Furthermore, solar radiation was estimated by [84] from sunshine-duration data from meteorological stations in Oman using linear and non-linear models.It was revealed from the results that the non-linear models performed markedly better compared to the linear ones.Moreover, Ref. [85] modelled the daily solar radiation for Oman using SVM.It was concluded that the SVM performs reasonably well in evaluating and predicting the solar radiation over the region.The optimum tilt angle of PV systems for Oman was also examined in [86].
The Omani government aims to generate about 30% of the country's energy demands from renewable energy sources by 2030 [87].For example, according to plans, the Ibri II solar PV independent plant project will generate 500 MW of power to supply the high energy demands in Oman's capital (Muscat) and northern Oman by 2040 [88].

Yemen
Solar radiation and the performance of solar cells over the city of Sana'a in Yemen are described in [89].The results showed that empirical models' estimations have good agreement with the measured values, while the performance of solar cells increased by 16% in winter if the solar panels were oriented towards the equator.
In another study, Ref. [90] investigated the global and diffuse solar radiation over Sana'a using the regression co-efficient of the Ångström correlation and an empirical model.The results showed good agreement between the estimated and measured values of solar radiation.It was also observed that the levels of both GHI and DHI vary with altitude.Furthermore, Ref. [91] estimated the solar radiation from sunshine-duration data utilizing the Ångström correlation.The evaluated results seemed satisfactory for Yemen.Subsequently, Ref. [92] predicted the monthly mean hourly clear-sky solar radiations on horizontal surfaces using [93], while [94] employed a methodology to estimate DHI.
The International Renewable Energy Agency (IRENA) reports assert that as of 2021, YE has a total energy capacity of about 253 MW [95].YE has some future plans to build a 120 MW solar plant in Adan as part of a cooperation agreement between the UAE and the YE Energy Ministry [96].The project is expected to be operational by the end of 2026.

Iraq
The topic of solar potential to generate solar energy has been less explored in Iraq, as only a few studies that illustrate the solar potential over Iraq are available.Solar radiation on horizontal surfaces, sunshine duration, maximum temperature and relative humidity for Baghdad, Mosul, and Rutaba were discussed in [61].Moreover, Ref. [97] mapped the monthly and annual solar radiation for Iraq using sunshine-duration data from 24 stations throughout the country.Similarly, Ref. [98] analyzed the performance of two single and two polynomial regression models to predict solar radiation over Iraq by using data on monthly mean sunshine duration based on daily measurements, maximum temperature, and relative humidity that had been collected from the Iraqi Meteorological Authority (IMA) and NASA.
The results exhibited that the single linear regression model with the aid of the IMA data performed reasonably well to predict solar radiation, as compared to other models.In addition, Ref. [99] utilized empirical models to estimate solar radiation over Iraq.However, the findings delineated the good agreement between estimated and measured values.
Iraq's energy production is mostly based on fossil fuels, as the country has the world's fifth-largest oil reserves [100][101][102].Large solar power plants in Iraq are mostly funded by KSA and UAE energy firms [103,104].In April 2023, the Saudi energy firm ACWA Power stated that it is planning to build a 1000 MW solar power plant near Najaf city in central Iraq [105].The Abu Dhabi-based Masdar Company is also planning to build four solar power plants in Iraq by 2025, with a total production capacity of 1000 MW [79,104,105].

Jordan
Several studies have been conducted to assess the solar potential over Jordan.The measured and simulated global and diffuse radiation over Jordan, along with various meteorological parameters, were compared in [106].The results showed a good agreement between measured and simulated data.Consequently, this study also included the optimized angle of inclination for each month of the year to maximize energy production.
Moreover, Ref. [107] mapped the solar radiation over Jordan and revealed that the region has enormous solar potential (average solar energy around 4-8 KWh/m 2 ).Similarly, Ref. [108] assessed the best way to predict the solar radiation over Jordan by employing various methods such as the Trees, Rules, Meta, lazy and Function methods.The findings revealed that prediction accuracy depends on the algorithm and the combination of variables.
The contribution of solar energy to the total energy for the years 2002 and 2007 was estimated in [109].The results showed that solar energy contributed around 1.2-1.7% in 2002 and that this rate increased up to 2.1% in 2007.Furthermore, Ref. [110] analyzed the global and diffuse solar radiation on horizontal surfaces over Amman (Jordan) during the period January-December 2008.The findings showed that the annual average daily global (diffuse) radiation is about 20.38 (4.5) MJ/m 2 .The prediction accuracy of the LSTM and ANFIS models over the Salt region was investigated in [111].The results revealed that the ANFIS model performs reasonably well, with cross-correlation coefficient values between measured and estimated values in the range 0.95-1, while the LSTM model showed crosscorrelation coefficients in the range 0.5-0.8[112].In another study, Ref. [113] used three ANN models such as Elman, Feedforward, and Non-linear Autoregressive Exogenous (NARX) to predict solar radiation in Amman.The findings showed that the performance of NARX is quite good as compared to those of Elman and Feedforward.The energy production from PV systems at three different sites in Jordan, including the northern, central, and southern (Ababa) regions was discussed in [114].The results revealed that the Ababa region is the optimum location to generate solar energy.Further, Ref. [115] studied the optimum angle of inclination for solar-energy generation throughout the year; the analysis illustrated a suitable tilt-angle range of 10 • -60 • .Monthly mean daily global radiation was estimated using multiple-regression models for six different climatic regions (i.e., Amman, Azraq, Al-Shawbak, Irbid, Ma'an, and Ababa) in [116].The findings displayed strong agreement between experimental and estimated solar-radiation data.The installation pattern (landscape and portrait) of photo-electric cells needed to achieve maximum output was highlighted in [117].The study concluded that a landscape pattern of PV cells shows high performance (13.7% increment) compared to a portrait pattern.The optimum axis (E-W, N-S) to generate solar energy efficiently was tested in [118].The results determined that N-S is the optimum orientation, with solar-power generation enhanced by about 30-40%.The resources for renewable energy, including wind and solar energy, at various locations in Jordan were discussed in [119].The investigation highlighted the great potential of wind and solar energy in various regions throughout the country.
Although Jordan has an average of 300 days of sunshine per year [107], making it suitable for harvesting solar radiation most of the year, the country is still mostly reliant on imported fossil fuels to secure its energy needs.Solar energy accounts for only about 5% of Jordan's electricity-production capacity [120].To increase solar-energy use in the country, Jordan has adopted several policies to attract investments to the solar-energy market, including facilitating, feeding and selling electricity generated by solar panels through the national grid [34].

Effects of Dust Storms
Dust and aerosols may play a significant role in reducing the efficiency of solar panels [121][122][123].

Saudi Arabia
The KSA has a complex topography, including three deserts: An-Nafud (northwest), Al-Dahna (east), and Rub Al-Khali (southeast).These deserts play a vital role in the GCC climate and serve as source regions for dust.On the other hand, there are some remote deserts such as the Sahara (in Africa), the Syrian (Al-Hajarah), and the Iraqi (Al-Dibdibah) deserts, which potentially serve as source regions to GCC and particularly to the KSA, which covers 80% of the land possessed by the GCC countries.Dust storms are mainly triggered through dynamical uplifting in the cold season, while diurnal vertical mixing causes dust storms in the warm season.In the KSA, dust storms commonly occur during February-June, along with a peak in March.The maximum dust activity occurs during mid-winter over the south of the Red Sea coast, in spring in the northern region of the KSA, and during summer in the eastern region of the KSA.During February-April, the Saharan cyclones associated with cold fronts transport dust to the KSA.Prediction of the effect of the major dust storms on solar energy was investigated in [124,125].Table 4 shows the frequency of dust storms per year in Saudi Arabia during the period 2010-2017.It can be observed that dust storms are more frequent during March-August.

United Arab Emirates
The main source regions of dust are the Rub Al-Khali and Iraqi deserts, which transport dust to the UAE.Moreover, the Haboob (the convective dust storm that is generated by the cool out-flow from a thunderstorm downdraft) contributes 30% of dust over the region.However, most of the dust storms occur during the March, April, and August months over the entire UAE territory.The dust storms start peaking in December, reach a maximum in March and decline to a minimum within August.

Qatar and Bahrain
There are four source regions of dust for Qatar and Bahrain, i.e., the Mesopotamian flood plain, the Nafud desert in the northwest region of the KSA that is the extension of the Syrian desert, and the Al-Dahna desert that connects the Nafud desert with the Rub Al-Khali one, this last region being another major dust source.The frequency of dust storms is higher in winter and summer in Qatar and Bahrain.

Oman and Yemen
The Rub Al-Khali desert is one of the major dust source regions for Oman and Yemen.However, the Saharan desert transports dust across the Red Sea.The frequency of dust storms is at its maximum in winter and spring.

Iraq
Iraq is one of the regions on Earth most vulnerable to climate change; the intensity and frequency of extreme weather events, particularly dust-storm events, are increasing over the region.These storms frequently occur in spring and summer when the northwestern Shimali wind lifts desert sand and silt from the Tigris and Euphrates River basins.Moreover, Iraq is also affected by southern and southeastern dry winds, which are known as Shargi; they occasionally cause gusts of 80 km/h from April to June and again from September to November.These winds cause violent dust to lift to several thousand meters.

Jordan
Jordan is located in the eastern Mediterranean region, where an arid-to-semi-arid climate prevails.Therefore, Jordan is highly exposed to dust storms.The Sahara Desert is one of the main source regions.Dust storms commonly occur from October to May.However, the maximum number of dust storms occur during the spring season (~54%), particularly in April (about 22.2%).
Figures 3 and 4 show the effect of dust loading in the atmosphere on reducing solar irradiance over the GCC region using MODIS/Terra data.Figure 3a shows high AOD values around the central region of the KSA during the 3 March 2009 dust events.Figure 4a shows the reduction of solar irradiance around similar geographic locations where high AOD was observed.Figure 3b,c show the effect of the 11 March 2009 and 18 March 2009 dust events on increasing aerosol loading in the western, central, and eastern regions of the GCC region and around the Arabian Gulf (also known as the Persian Gulf). Figure 4b,c indicate low solar irradiance above the regions affected by the storm.Moreover, high solar irradiance was observed over the southern regions of the GCC, where less dust loading was observed compared to the western, central, and eastern parts of the GCC.Similarly, Figure 3d shows the high dust loading over the western side of the GCC and the Red Sea during the 20 March 2012 dust event, while Figure 4d shows the reduction of solar irradiance over the same region during the storm.Figures 3e,f and 4e,f

Solar Radiation and PV Electricity
Figure 5 illustrates the distribution of DNI over the study area, which indicates the amount of solar energy per m 2 on solar panels that receive solar rays normal to their surface.It can be observed that DNI ranges from 1800 to 3500 kWh/m 2 .The highest DNI values are observed over northwestern Saudi Arabia, Jordan, the western part of Iraq, and almost all of Yemen.These areas could be suitable for installing PV systems.Tables 6 and  7 and Figure 6a1-h2 show the total PV Power Output (PVPO) and DNI at Riyadh, Abu Dhabi, Doha, Manama, Muscat, Sana'a, Amman, and Baghdad, the capitals of Saudi Arabia, UAE, Qatar, Bahrain, Oman, Yemen, Jordan, and Iraq, respectively.

Solar Radiation and PV Electricity
Figure 5 illustrates the distribution of DNI over the study area, which indicates the amount of solar energy per m 2 on solar panels that receive solar rays normal to their surface.It can be observed that DNI ranges from 1800 to 3500 kWh/m 2 .The highest DNI values are observed over northwestern Saudi Arabia, Jordan, the western part of Iraq, and almost all of Yemen.These areas could be suitable for installing PV systems.Tables 6 and 7 and Figure 6a1-h2 show the total PV Power Output (PVPO) and DNI at Riyadh, Abu Dhabi, Doha, Manama, Muscat, Sana'a, Amman, and Baghdad, the capitals of Saudi Arabia, UAE, Qatar, Bahrain, Oman, Yemen, Jordan, and Iraq, respectively.Average PVPO and DNI values in Riyadh, Abu Dhabi, Doha, Manama, and Muscat range from ~125 to 165 kWh and ~105-215 kWh/m 2 , respectively.In Sana'a, Amman, and Baghdad, the PVPO and DNI range from ~107 to 179 kWh and ~98-305 kWh/m 2 , respectively.Riyadh, Abu Dhabi, Doha, Manama also experience high DNI during the period May-October, with the highest DNI values recorded in Riyadh and Manama, while Muscat shows a decrease in DNI during the summer months.Meanwhile, a positive correlation was found between PVPO and DNI, with R 2 values of ~0.61, 0.57, 0.66, 0.75, 0.54, 0.96, 0.86, and 0.85 in Riyadh, Abu Dhabi, Doha, Manama, Muscat, Sana'a, Amman, and Baghdad, respectively.Meanwhile, among the countries' capitals of Amman, Jordan, and Sana'a, Yemen receives the highest DNI.
Table 8 shows the average hourly PVPO values from 9:00 am to 3:00 pm during January-December in the capitals of Riyadh, Abu Dhabi, Doha, Manama, Muscat, Sana'a, Amman, and Baghdad.It can be observed that the maximum power output occurs from 11:00 am to 1:00 pm, with the greatest power output observed in Sana'a and Amman.Table 8.Average hourly (9:00 am-3:00 pm) PVPO (in kWh) January-December (2012-2022) in Riyadh, Abu Dhabi, Doha, Manama, Muscat, Sana'a, Amman, and Baghdad.Color codes: green: 300-500 kWh; yellow: 500-600 kWh; purple 600-800 kWh [33].Figure 7 shows the electricity generation from oil, natural gas, coal, nuclear energy, hydroelectricity, and renewable energy sources in Saudi Arabia, UAE, Qatar, Oman, and Iraq from 2012 to 2022 [129].A growing demand for electricity is observed in all countries due to increasing population and expansion of industrial activities [130,131].Saudi Arabia surpasses other countries in the study region, with an energy demand of at least 150% that of other countries.Meanwhile, the growth rates of electricity generation in Saudi Arabia, UAE, Qatar, Oman, and Iraq are illustrated in Figure 8, where the red bars represent average growth in electricity generation in 2012-2022 and blue bars represent average growth in electricity generation for 2022 only.It can be observed that in 2022, all countries showed lower rates of electricity generation compared to the period 2012-2022.This can be related to increased efficiency of use and reliance on more renewable energy sources.During 2022, Qatar showed a negative growth rate per annum of electricity generation, a fact that could be related to hosting the FIFA World Cup 2022 in Qatar [132], which encouraged the country to optimize electricity generation to improve air quality through reducing greenhouse-gases emissions resulting from burning fossil fuels for electricity production [133].Figure 7 shows the electricity generation from oil, natural gas, coal, nuclear hydroelectricity, and renewable energy sources in Saudi Arabia, UAE, Qatar, Om Iraq from 2012 to 2022 [129].A growing demand for electricity is observed in all co due to increasing population and expansion of industrial activities [130,131].Saudi be related to increased efficiency of use and reliance on more renewable energy sources.During 2022, Qatar showed a negative growth rate per annum of electricity generation, a fact that could be related to hosting the FIFA World Cup 2022 in Qatar [132], which encouraged the country to optimize electricity generation to improve air quality through reducing greenhouse-gases emissions resulting from burning fossil fuels for electricity production [133].Figure 9 shows the share of renewable energy out of all generated electricity compared to other sources in Saudi Arabia and UAE during 2021 and 2022.It can be observed that oil and natural-gas sources are still in high demand compared to renewable energy sources in both countries.Data related to electricity generation per annum are not available for other countries in the study region from 2012 to 2022 [129].Figure 9 shows the share of renewable energy out of all generated electricity compared to other sources in Saudi Arabia and UAE during 2021 and 2022.It can be observed that oil and natural-gas sources are still in high demand compared to renewable energy sources in both countries.Data related to electricity generation per annum are not available for other countries in the study region from 2012 to 2022 [129].
be related to increased efficiency of use and reliance on more renewable energy sources.During 2022, Qatar showed a negative growth rate per annum of electricity generation, a fact that could be related to hosting the FIFA World Cup 2022 in Qatar [132], which encouraged the country to optimize electricity generation to improve air quality through reducing greenhouse-gases emissions resulting from burning fossil fuels for electricity production [133].Figure 9 shows the share of renewable energy out of all generated electricity compared to other sources in Saudi Arabia and UAE during 2021 and 2022.It can be observed that oil and natural-gas sources are still in high demand compared to renewable energy sources in both countries.Data related to electricity generation per annum are not available for other countries in the study region from 2012 to 2022 [129].

Carbon Savings of PV Panels
Carbon savings associated with PV panels versus grid electricity in each country were calculated, where PV panels are assumed to have 0 kg CO 2 operational emissions per kWh. Figure 10 Oman, Yemen, Iraq, and Jordan based on electricity production by PV panels based on the assumption that solar energy can efficiently replace oil and natural gas to generate electricity.In Saudi Arabia, electricity generation from PV panels has increased from 4 GWh (in 2010)-804 GWh (in 2021).This has been reflected in a reduction in CO 2 by ~0.

Carbon Savings of PV Panels
Carbon savings associated with PV panels versus grid electricity in each country were calculated, where PV panels are assumed to have 0 kg CO2 operational emissions per kWh. Figure 10 shows the CO2 reductions from 2000-2021 in Saudi Arabia, UAE, Oman, Yemen, Iraq, and Jordan based on electricity production by PV panels based on the assumption that solar energy can efficiently replace oil and natural gas to generate electricity.In Saudi Arabia, electricity generation from PV panels has increased from 4 GWh (in 2010)-804 GWh (in 2021).This has been reflected in a reduction in CO2 by ~0.No reliable data are available regarding electricity generation from solar PV in Qatar and Bahrain.The above findings can be considered as lessons in grid decarbonization by using PVs for arid regions that are reliant on fossil fuels.

Workflow Model
A workflow model that can be adopted by local governments and stakeholders to gradually implement PV panels as a major source of electricity is proposed for the study region.
As shown in Figure 11, the model presented in the workflow diagram is based on the pre-existence of some PV solar projects in many countries of the study region.According to the literature, countries like the KSA and the UAE have the largest investments in PV installation compared to other countries in the study region.The current study suggests the evaluation of the scale, efficiency, and capacity of the current PV projects.This will help decision-makers decide the number of new PV projects that need to be installed.Each country should then establish a solar-energy policy that suits the country's national regulations and economic situation.This solar-energy policy could include (1) subsidizing solar energy; (2) encouraging installation of solar panels in the private and public sectors; To encourage individuals and investors to use solar renewable energy rather than fossil fuels, this study suggests that governments should subsidize PV panels.This subsidization could be in the form of reduced customs tariffs or financial incentives like rebates, tax credits, and grants.Such incentives could lead private and public sectors to add more PV panels to the network and thus reduce dependence on fossil fuel.Such energy-subsidization policies could encourage private and public sectors to increase their dependence To encourage individuals and investors to use solar renewable energy rather than fossil fuels, this study suggests that governments should subsidize PV panels.This subsidization could be in the form of reduced customs tariffs or financial incentives like rebates, tax credits, and grants.Such incentives could lead private and public sectors to add more PV panels to the network and thus reduce dependence on fossil fuel.Such energy-subsidization policies could encourage private and public sectors to increase their dependence on solar energy by installing more solar panels.This will lead to an increase in the percentage contribution of solar energy to overall electricity production, which could eventually lead to meeting power demands through solar energy.This could eventually lead to a solar renewable energy surplus that allows energy to be exported, leading to better economic development and job opportunities.An energy surplus could help in establishing electricity interconnection among countries in the study region.

Discussion
The rapid economic upswing in the GCC region and population growth in Yemen, Iraq, and Jordan have created a large gap between demand and the supply of energy; on the other hand, over-dependence on fossil fuels and their subsidization have severe health, environmental, and socio-economic effects.As fossil-energy sources including natural gas, coal, and oil are non-renewable, the countries in the study area should search for more stable, reliable, and abundant renewable energy sources to cover their high energy demands, though the highly abundant solar energy in those countries is still untapped.In addition to their environmental benefits, advancements in PV technology have increased the efficiency of solar panels, which makes them one of the best solutions to generate sustainable and clean energy.In addition to the need to meet energy demands, the responsibility of the oil-rich countries to reduce global warming has led many countries of the region to invest in PV solar energy projects and connect them to the electricity grid.
While most of the countries considered in this work are geographically located in a solar-belt region where they receive significant amounts of solar energy, the establishment of large PV projects faces many challenges, some of which appear to be the abundance of subsidized oil products, vast desert areas, and dust storms.
In the GCC area, only Saudi Arabia and the UAE have established relatively highcapacity solar PV projects, which do not reflect their strong financial systems or the abundant solar energy available.The two countries, however, have rigorous initiatives to expand the use of solar energy through the 2030 Saudi and 2031 UAE Visions.Among Yemen, Iraq, and Jordan, only Jordan has some reliable PV projects; this is attributed to the high energy prices, which causes people to rely on a more affordable solar solution.The PV capacity in Jordan, however, is very low and does not cover the high energy demands in the country.
Dust is negatively affecting the performance of solar panels due to scattering and absorption of solar radiation and due to its deposition on solar panels.Frequent dust storms in the study region, especially in the KSA, the UAE, and Iraq may lead to significant energy loss in the PVs.Thereby, dust is a major issue that can be an obstacle to relying on PV technology to harvest solar radiation in the study region.In this context, further research is recommended concerning an approach that can use solar panels to generate sustained power during their lifetime.
Benchmarking the use of solar energy against that of other countries that may have conditions similar to those of the study region in terms of the amount of solar energy, landscape, and meteorological conditions could help decision makers set realistic goals for adopting renewable solar energy.For example, about 70% of Australia is covered by arid/semiarid zones [128] and it has climatological and solar radiation conditions similar to those of the countries considered in this work.
Australia's successful implementation of solar energy over the last 15 years could give countries in the study region insights into their own successful future transition to renewable energy.The latest edition of the Clean Energy Australia Report, released on 18 April 2023, states that 310 k new rooftop [129] PV solar systems, accounting for 2.7 GW of power, were added to the electric grid in 2022; this amount is nearly 4% of the capacity of electricity generation in Saudi Arabia in 2021 [130].Increased public awareness and engagement about the economic and environmental advantages of solar energy led to more than 3.2 m Australian households using solar energy technology as in June 2022, while that number was only 1.3 m in June 2018 [130].In terms of business, more than 54,805 businesses in Australia had solar panels installed from 2014 to 2023 [129], which has resulted in a large reduction in their power bills, with an average saving of about AUD400 per year per kW [128].This indicates that households and businesses in Australia are taking advantage of the abundance of solar energy in the country to supply some of their electrical power needs.Countries in the region studied in the present work that want to reduce their dependence on fossil fuels or that suffer from high energy prices should try to follow the Australian model.The approaches that have made solar energy so popular in Australia should be considered in the study region.These approaches include encouraging small and large businesses to invest in PV technology and providing financial benefits to allow homeowners in residential areas to install rooftop PV panels.Additionally, Australia's model of investing in research and development related to improving PV technology and installing PV panels in remote areas should be considered in the study area.
It is recommended that countries in the study region increase national and governmental funds devoted to the research and development sectors related to PV technology.To date, only small research projects related to solar-panel effeminacy, performance, and tilt angle have been implemented.More research is needed to enhance solar PV performance across each country and to produce innovations in the solar-energy sector that would suit the local conditions.Research funds related to the fossil-fuel industry outnumber funds allocated to renewable-energy projects.
Meanwhile, new governmental rules should be adopted in the study area to ensure minimum standards for importing and certifying solar panels.This would ensure PV panels' quality, performance, design quantification, and safety.All solar PV panels should be subjected to rigorous tests for certification prior being integrated to the grid.
The expansion of PV infrastructure in the study area should be accompanied by training of individuals to install and maintain solar panels.Dust deposition on the panels is another problem that reduces their efficiency and requires a large work force for regular cleaning.Professional training is also required to avoid mistakes in PV installation, especially mistakes related to safety and electrical work.
Parameters related to solar PV maintenance are understudied in the countries considered in this work, especially those related to dust deposition, accidental damage, environmental conditions, robotic cleaning, and shading.As most of these parameters are site-specific, more research is desired to ensure the optimum yield and performance of solar panels in the study region.
Policymakers in these countries should adopt legislation to make solar PV more affordable to the public.This can be done by reducing customs tariffs and offering tax reductions associated with solar-panel installation.This governmental financial support could reduce the initial costs of establishing PV technology in these countries.
Workshops and events should be planned in the study region to make the public aware of the opportunities associated with using solar energy as one of the alternatives to fossil fuels and to encourage the public to use it.Students and school pupils should attend seminars about the effects of burning fossil fuels on health and the environment.Both private and public organizations should participate in this community-awareness effort.
Security and surveillance cameras should be provided in the solar PV locations to minimize trespassing, theft, and vandalism of the solar panels and their ground bases.
Solar energy is abundantly available in the eight countries considered in this work and can be used to supply off-the-grid electricity, especially in desert areas and in lowincome countries with relatively high energy demands.Using solar energy could reduce the environmental and health impacts of fossil fuels.
Countries in the study region have not yet taken advantage of the abundant solar energy due to their high reliance on fossil fuels and due to the lack of specific regulations regarding solar energy.This study recommends an investigation of such challenges to enable the optimum use of the PV technology in the study region.
One of the limitations of this work is that although the study region is very rich in ground-based data, most of these data are not publicly available, which makes it difficult to form a full image of the status of PV projects in the region based on the published research alone.

Conclusions
This study attempted to elucidate the potential of the GCC countries, Yemen, Iraq, and Jordan, to adopt solar energy as an alternative renewable energy source.It was found that despite the enormous abundance and sustainability of solar irradiance in the study region, only a few countries have invested in developing a reliable PV infrastructure to harvest solar energy.The shortage of suitable infrastructure for PV panels was found to be the main obstacle to the widespread adoption of solar energy in the study area.Despite the existence of advanced PV technology that could be suitable for the environmental and meteorological conditions of the region, challenges persist in integrating these systems into existing infrastructure.Issues such as low grid capacity, lack of standardized regulations, and limited financial support constrain the establishment of PV-panel infrastructure on a large scale.Without robust infrastructure to support the generation and distribution of electricity generated by PV plants, it will be difficult to adopt solar energy in the study area.Policymakers, industry stakeholders, and homeowners need to invest in upgrading infrastructure and implementing supportive regulations that encourage the expansion of PV-panel projects.
Countries in the study region depend on fossil fuels as a major energy source, almost the only energy source, to cover their energy needs.This has created a few environmental and health effects due to loading of anthropogenic aerosols in the atmosphere from the burning of fossil fuels.Rapid economic growth, water-desalination plants, cement, and petrochemical industries in the oil-rich GCC countries and the growing population in Yemen, Iraq, and Jordan have created a high energy demand.Moreover, subsidized oil and gas prices in the GCC countries have led to overconsumption of fossil fuels, which further increased energy demands.
To reduce the social economic and environmental impacts of fossil fuels, countries in the study region need to use solar energy sources to cover their growing energy demands and develop their economies.
Dust (natural and anthropogenic) is one of the main barriers to adopting solar energy in the study area, as it significantly reduces the performance of solar PV panels through the absorption and scattering of solar radiation and deposition on the solar panels.Tracking dust pathways during large dust events is important to understanding dust particles' physical and morphological characteristics, in addition to dust dynamics and deposition.Major dust events were found to take place in the study area during the spring and fall seasons.Large dust events were more frequent in 2013 and 2015, especially over the GCC area and in Iraq.Large dust storms were found to significantly reduce solar irradiance in central Saudi Arabia, Qatar, Bahrain, and Iraq, while dust storms have a smaller impact on solar irradiance in the UAE, Oman, Yemen, and Jordan.The study found that only Saudi Arabia, the UAE, Yemen, Iraq, and Jordan have established some limited solar PV projects, with limited electricity production that does not significantly offset the CO 2 footprint from fossil-fuel sources.
Governments in the study-area countries should establish common frameworks, policies, and regulations that support the implementation of solar energy as a major source for power generation.Benchmarking against other countries that share similar climate and landscape conditions, like Australia, which has successfully implemented solar-energy projects, can help in setting renewable-energy policies and encourage households and pri-vate sectors to consider PV panels to avail themselves of this opportunity.Meanwhile, this work introduced a flow chart showing how to evaluate the scale, efficiency, and capacity of current PV projects for countries in the study region.The model can help decision-makers optimize the use of solar energy for electricity production.
The operation of PV power plants can be unstable due to weather conditions.There is also no energy generation at night.Future work should consider energy-storage systems for PV power plants in the study region.
The data available in this study are limited by the amount of data that is publicly available.Many ground stations are available in the study region.Making data more available to researchers could help in improving models and understanding patterns of solar radiation in the study region.

3 Figure 1 .
Figure 1.Map of the region containing the GCC countries, Yemen, Iraq, and Jordan.

Figure 1 .
Figure 1.Map of the region containing the GCC countries, Yemen, Iraq, and Jordan.

Figure 2 5 Figure 2 .
Figure 2. Flow chart of the methodology used in this study.

Figure 2 .
Figure 2. Flow chart of the methodology used in this study.
Figures3 and 4show the effect of dust loading in the atmosphere on reducing solar irradiance over the GCC region using MODIS/Terra data.Figure3ashows high AOD values around the central region of the KSA during the 3 March 2009 dust events.Figure4ashows the reduction of solar irradiance around similar geographic locations where high AOD was observed.Figure3b,cshow the effect of the 11 March 2009 and 18 March 2009 dust events on increasing aerosol loading in the western, central, and eastern regions of the GCC region and around the Arabian Gulf (also known as the Persian Gulf).Figure4b,cindicate low solar irradiance above the regions affected by the storm.Moreover, high solar irradiance was observed over the southern regions of the GCC, where less dust loading was observed compared to the western, central, and eastern parts of the GCC.Similarly, Figure3dshows the high dust loading over the western side of the GCC and the Red Sea during the 20 March 2012 dust event, while Figure4dshows the reduction of solar irradiance over the same region during the storm.Figures3e,f and 4e,f show the effect of dust loading on solar irradiance over GCC during 27 March 2012 and 3 April 2012.

Figure 7
Figure 7 Electricity generation in MWh from all sources (conventional and renewable) in Sau bia, UAE, Qatar, Oman, and Iraq from 2012 to 2022 [129].

Figure 7 .
Figure 7. Electricity generation in MWh from all sources (conventional and renewable) in Saudi Arabia, UAE, Qatar, Oman, and Iraq from 2012 to 2022 [129].

Figure 8 .
Figure 8. Growth rate per annum of electricity generation from all sources (conventional and renewable) in Saudi Arabia, UAE, Qatar, Oman, and Iraq during 2012-2022 and in 2022 [129].

Figure 8 .
Figure 8. Growth rate per annum of electricity generation from all sources (conventional and renewable) in Saudi Arabia, UAE, Qatar, Oman, and Iraq during 2012-2022 and in 2022 [129].

Figure 8 .
Figure 8. Growth rate per annum of electricity generation from all sources (conventional and renewable) in Saudi Arabia, UAE, Qatar, Oman, and Iraq during 2012-2022 and in 2022 [129].

5
Mt in 2021 compared to ~0.003 in 2010 if emissions from oil are considered and ~0.42 Mt in 2021 compared to ~0.002 in 2010 if emissions from natural gas are considered.In the UAE, electricity generation from PV panels has increased from 18 GWh in 2010 to 5982 GWh in 2021.This has been reflected in a reduction in CO 2 by ~4.8 Mt in 2021 compared to ~0.01 Mt in 2010 if emissions from oil are considered and ~3.1 Mt in 2021 compared to ~0.01 Mt in 2010 if emissions from natural gas are considered.In Oman, electricity generation from PV panels has increased from 1 GWh in 2013 to 260 GWh in 2021.This has been reflected in a reduction in CO 2 by ~0.19 Mt in 2021 compared to ~0.0007 Mt in 2013 if emissions from oil are considered and ~0.09Mt in 2021 compared to ~0.0005 Mt in 2010 if emissions from natural gas are considered.In Yemen, electricity generation from PV panels has increased from 2 GWh in 2010 to 490 GWh in 2021.This has been reflected in a reduction in CO 2 by ~0.39 Mt in 2021 compared to ~0.001 Mt in 2010 if emissions from oil are considered and ~0.31 Mt in 2021 compared to in 2010 if emissions from natural gas are considered.

5 23 Figure 10 .
Figure 10.CO2 reduction based on electricity generation by solar PV in (a) Saudi Arabia, (b) the UAE, (c) Oman, (d) Yemen, (e) Iraq, and (f) Jordan.In the UAE, electricity generation from PV panels has increased from 18 GWh in 2010 to 5982 GWh in 2021.This has been reflected in a reduction in CO2 by ~4.8 Mt in 2021 compared to ~0.01 Mt in 2010 if emissions from oil are considered and ~3.1 Mt in 2021 compared to ~0.01 Mt in 2010 if emissions from natural gas are considered.In Oman, electricity generation from PV panels has increased from 1 GWh in 2013 to 260 GWh in 2021.This has been reflected in a reduction in CO2 by ~0.19 Mt in 2021 compared to ~0.0007 Mt in 2013 if emissions from oil are considered and ~0.09Mt in 2021 compared to ~0.0005 Mt in 2010 if emissions from natural gas are considered.In Yemen, electricity generation from PV panels has increased from 2 GWh in 2010 to 490 GWh in 2021.This has been reflected in a reduction in CO2 by ~0.39 Mt in 2021 compared to ~0.001 Mt in 2010 if emissions from oil are considered and ~0.31 Mt in 2021 compared to ~0.0012 Mt in 2010 if emissions from natural gas are considered.In Iraq, the electricity generation from PV panels has increased from 46 GWh in 2013 to 57 GWh in 2021.This has been reflected in a reduction in CO2 by ~0.05 Mt in 2021 compared to ~0.04 Mt in 2013 if emissions from oil are considered and ~0.03 Mt in 2021 compared to ~0.02 Mt in 2013 if emissions from natural gas are considered.In Jordan, the electricity generation from PV panels has increased from 2 GWh in 2015 to 3290 GWh in 2021.This has been reflected in a reduction in CO2 by ~2.79 Mt in

Figure 10 .
Figure 10.CO 2 reduction based on electricity generation by solar PV in (a) Saudi Arabia, (b) the UAE, (c) Oman, (d) Yemen, (e) Iraq, and (f) Jordan.In Iraq, the electricity generation from PV panels has increased from 46 GWh in 2013 to 57 GWh in 2021.This has been reflected in a reduction in CO 2 by ~0.05 Mt in 2021 compared to ~0.04 Mt in 2013 if emissions from oil are considered and ~0.03 Mt in 2021 compared to ~0.02 Mt in 2013 if emissions from natural gas are considered.In Jordan, the electricity generation from PV panels has increased from 2 GWh in 2015 to 3290 GWh in 2021.This has been reflected in a reduction in CO 2 by ~2.79 Mt in 2021 compared to ~0.001 Mt in 2015 if emissions from oil are considered and ~1.5 Mt in 2021 compared to ~0.0009 Mt in 2015 if considering emissions from natural gas are considered.No reliable data are available regarding electricity generation from solar PV in Qatar and Bahrain.The above findings can be considered as lessons in grid decarbonization by using PVs for arid regions that are reliant on fossil fuels.

( 3 ) 24 Figure 11 .
Figure 11.Workflow diagram for expanding the use of PV panels in the study region.

Figure 11 .
Figure 11.Workflow diagram for expanding the use of PV panels in the study region.

Author Contributions:
Conceptualization, methodology, data analysis, writing-original draft preparation, A.F., data retrieval, data analysis A.F. and A.H.L. and H.M.H., writing-review A.F., A.H.L., A.-W.S.M. and H.D.K. and editing, A.F., H.M.H. and H.D.K.All authors have read and agreed to the published version of the manuscript.

Funding:
Authors would like to acknowledge the support provided by the Center of Research Excellence in Aviation and Space Exploration through the Deanship of Research Oversight and Coordination (DROC) at the King Fahd University of Petroleum and Minerals (KFUPM) for funding this work through project No. INAE2303.

Table 1 .
Approximate coordinates of PV plants in the countries.SSP: Sakaka Solar Plant; LSP: Layla

Table 2 .
Weather conditions in the study region.MC: Mostly Cloudy; SC: Scattered Clouds; Cl: Clear; BC: Broken Clouds; PC: Passing Cloud; DS: Dust Storm; ND: No Data; Hz: Haze.

Table 4 .
Number of dust storms per year in Saudi Arabia during the period 2010-2017 [126].