## 3 Results and Discussion
### Mapping of the Wind Energy Potential
The map of the annual mean wind speed over Iran (Figure 7) reveals that the areas with the highest wind energy potential are located on top of high mountain ridges and in wind corridors, such as mountain passes. These areas, classified into class 3 (6.4-7 m/s) and above, are found in the high mountain ranges and in the Sistan Basin. However, for the mountain ranges, the wind speed and direction may be highly sensitive to atmospheric circulation and thermodynamics [114]. The wind-climatology map demonstrates that Iran has numerous regions with good or excellent wind energy potential. However, the Kavir and Lut Deserts in the interior of Iran generally have low Aeolian potential on an annual basis, with a notable seasonality. The Aeolian regime in these desert regions, along with annual and intra-seasonal variability, play a significant role in land degradation and wind erosion from the deserts and arid rangelands in central Iran [115; 116; 117]. Certain valleys and wind corridors along the eastern borders of Iran exhibit wind speeds of up to class 6 in terms of the annual average wind speed categorization. The channeling effect in these valleys intensifies wind intensity and modifies wind shear compared to the regional wind regime influenced by pressure gradients [105; 106; 107; 108]. Prevailing strong winds in eastern Iran are mainly northwesterlies, aligning with the orientation of the valley corridors [111]. The Lut Valley Gap area frequently experiences strong northerly winds due to the channeling of wind flow between the topographic low belt and tall snowy mountains. These wind corridors exhibit pronounced seasonal variations in wind power density, with a peak during summer. However, other valleys and basins in the Iranian interior that lack suitable orientation in relation to the main wind flow display significantly reduced wind resources. In Figure 7, the sites marked with black triangles represent regions where wind farms have been already established. Characteristically, the annual mean simulated wind speed in the Manjil region is approximately 7.82 m/s, in Kahak it is 6.71 m/s, and in Binaloud it is 7.11 m/s, corresponding to wind classes 5, 3 and 4, respectively. It is observed that possible wind farms in the Sistan Basin in eastern Iran would fall into the upper class 7, as the annual mean wind speed has been measured at above 8-10 m/s at the Zabol station over the long term [106; 117; 118]. However, despite this very outstanding wind energy potential in the Sistan Basin and surrounding areas, no wind farms or Aeolian Parks have  
Figure 7: Simulated mean wind speed at 50 m a.g.l. during the period 2004–2020 over Iran. The black triangles show the locations of installed wind farms: (A) Agh Kand, (B) Binaloud, (K) Kahak, (Kh) Khaf, (L) Lutak, (M) Manjil, (Ma) Mahshah, (N) Neyshabur, (S) Sahand, (Sa) Sarab, (Se) Seyabpush, (Sr) Sareyn. The rectangles correspond to 10 areas (A1–A10), with sufficient wind potential, where long-term wind speed trends were calculated. been developed there so far. Therefore, this wind atlas for Iran highlights areas where a high level of wind resources may exist but have not been fully exploited. In addition, ten areas with sufficient wind energy potential were detected in Figure 7 (10 rectangles), distributed over the Iranian territory except for the central Iranian Plateau. For these areas, the monthly mean wind speeds, averaged over the 17-year period (2004-2020) according to WRF simulations, are shown in Figure 8, which highlights the significantly higher wind potential in the summer months over areas like A1 and A2. In addition, the annual variability underscores the existence of two discernible wind patterns, each characterized by distinct seasonal variations. The first pattern aligns with the warm months, spanning from May to October, while the second is associated with the colder months, spanning from November to April. Throughout the colder season, minimal disparities in wind speeds are observed, with monthly mean wind speeds ranging from approximately 5.5 m/s to 7 m/s.