## 3 Results and Discussion
### Mapping of the Wind Energy Potential  
Overall, the total runs of the WRF model generated approximately 280 billion wind records (spatial resolution of 5 km \(\times\) 5 km) over the Iranian territory, collected at levels near the Earth's surface, specifically up to a height of 200 m above ground level. To assess the wind energy potential, monthly and seasonal averages of wind speed were analyzed at different heights, particularly at 50 m a.g.I, which is the mean height for wind turbines. The spatial distribution of wind speed over Iran at this height is shown in Figures 5-7, on a monthly, seasonal and annual basis, respectively, covering the period 2004-2020. Based on the classification proposed by [PERSON] et al. [72], the wind energy potential of an area can be categorized into seven groups according to the average wind speed (AWS) at 50 m. These categories include Poor (AWS less than 5.6 m/s), Marginal (AWS of 5.6-6.4 m/s), Fair (AWS of 6.4 to 7 m/s), Good (WS of 7-7.5 m/s), Excellent (WS of 7.5-8 m/s), Outstanding (WS of 8-8.8 m/s), and Very Outstanding (above 8.8 m/s) wind energy potential. Monthly, seasonal, and annual AWS at 50 m were assessed according to this classification, as shown in Figures 5-7. Figure 5 illustrates the spatial distribution of the monthly average wind speed at 50 m, starting with November, which had the lowest spatial mean wind speed. The results show that wind speeds were generally low in November, December and January, but increased from February to April in certain parts along the eastern Iranian borders, the Zagros and Alborz Mountains, and areas near the Caspian Sea and Persian Gulf. The highest wind speeds were observed from June to August, particularly in the eastern (Levar wind) and southwestern (Shamal wind) regions of the country. The strong northerly Levar flow creates an exceptional source of renewable energy and wind energy potential over the Sistan Basin and eastern regions of Iran (Figure 5g-k). By the end of the warm season, and due to changes in atmospheric circulation in central and south Asia, the wind speed gradually decreases as Levar dissipates [106]. Figure 4: Mean wind speeds (m/s) at heights of 50 m and 100 m, as generated by the WRF simulations (**a**,**c**) and the DTU wind Atlas (**b**,**d**) over Iran, along with their differences at 50 m (**e**) and 100 m (**f**). The topographic map of Iran is shown in (**g**). Figure 5: Spatial distribution of the simulated monthly mean wind speeds at 50 m a.g.l. during 2004-2020 in Iran. These findings align with previous studies conducted in the eastern part of Iran, specifically in the Sistan Basin [106, 111, 112, 113]. Consequently, the highest wind energy potential in Iran is identified along the eastern borders with Afghanistan, primarily due to the strong Levar wind that blows during the warm period of the year from May to October. Figure 6 presents the simulations of seasonal mean 50 m wind speeds. During the winter season, only some narrow bands of high wind speeds are observed along the mountainous areas, mainly in the Zagros Mountains, while weaker winds are observed over the Persian Gulf and the central Iranian Plateau (Figure 6a). In spring, wind speeds in the mountainous areas decrease compared to winter, but they significantly increase in the eastern part of Iran with less intensity in the western and southwestern regions of the country (Figure 6b). During the summer season, the wind intensity as well as the area covered by strong winds in the eastern part of the country increase, while areas with high wind speeds in the west and southwest decrease (Figure 6c). In autumn, wind speeds are generally low throughout the country, except for some small areas with stronger winds in the eastern part (Figure 6d). Figure 6: Spatial distribution of the simulated seasonal mean wind speed at 50 m a.g.l. during the period 2004–2020 for (**a**) winter (JFM), (**b**) spring (AMJ), (**c**) summer (JJA) and (**d**) Autumn (OND).