
Figure 1
Geographical location of the Barents Sea and the sea area within the inner sector is the selected domain for the statistical study

Figure 2
Annual average, mean monthly maximum (April), minimum (September) distributions of the sea ice concentration and the ice zone partitions. In the ice-free zone, the points labeled from P1 to P1 are selected for further wind climate and energy analysis.
Table 1
Four extreme value distribution functions
| Distribution type | Probability density distribution function f(x) | Parameters |
|---|---|---|
| GEV | μ-location parameter α-scale parameter β-shape parameter | |
| Gumbel | μ-location parameter α-scale parameter | |
| Weibull | μ-location parameter β-shape parameter α-scale parameter | |
| P-III | μ-location parameter β-shape parameter α-scale parameter |

Figure 3
Spatial distributions of annual average wind speed at 10 m

Figure 4
Spatial distributions of mean seasonal wind speed at 10 m from winter to autumn

Figure 5
Wind roses from P1 to P7 in the Barents Sea. The color scale represents wind speed classification

Figure 6
Spatial distributions of annual average wind speed and power density at 100 m

Figure 7
Spatial distributions of mean seasonal wind speed at 100 m from winter to autumn

Figure 8
Spatial distributions of mean seasonal wind power density at 100 m from winter to autumn
Table 2
Parameters of model wind turbine generators for CCWE3000D and SL500
| WTGs | Rated power (kW) | Hub height (m) | Rotor diameter (m) | Cut-in wind speed (m s−1) | Rated wind speed (m s−1) | Cut-out wind speed (m s−1) |
|---|---|---|---|---|---|---|
| CCWE3000D | 3000 | 100 | 103 | 3 | 12 | 25 |
| SL500 | 5000 | 100 | 128 | 3.5 | 12.5 | 25 |

Figure 9
Interannual variations of annual average wind power density at 100 m from P1 to P7 in 1996–2015
Table 3
Locations of the selected points and 100 m annual average wind speeds, wind power density (WPD) and net electric energy output from P1 to P7
| Points | Longitude (N) | Latitude (E) | Mean speed (m s−1) | WPD (W m−2) | Electric energy (MWhy) | |
|---|---|---|---|---|---|---|
| CCWE3000D | SL500 | |||||
| P1 | 22 | 74 | 10.23 | 1108 | 14 384 | 23 534 |
| P2 | 22 | 72 | 9.99 | 1041 | 14 002 | 22 855 |
| P3 | 32 | 74 | 10.26 | 1097 | 14 535 | 23 776 |
| P4 | 35 | 72 | 10.10 | 1046 | 14 312 | 23 390 |
| P5 | 42 | 73 | 9.91 | 985 | 14 011 | 22 873 |
| P6 | 42 | 71 | 9.95 | 991 | 14 121 | 23 064 |
| P7 | 37 | 70 | 9.96 | 1002 | 14 118 | 23 079 |

Figure 10
Power output curves for wind turbine generators
Table 4
Comparisons of the K-S test and RMSE between GEV, Gumbel, Weibull and P-III distributions
| Distributions | K-S test | Mean | Maximum | Minimum |
|---|---|---|---|---|
| RMSE | RMSE | RMSE | ||
| GEV | 99.97% | 0.0484 | 0.1700 | 0.0210 |
| Gumbel | 99.96% | 0.0591 | 0.1353 | 0.0174 |
| Weibull | 98.56% | 0.0473 | 0.2957 | 0.0191 |
| P-III | 100%* | 0.0434* | 0.1061* | 0.0153* |
[i] Note: Results of the K-S test in this study mean in fact the passing rate of all grids in the whole domain with the significance level of 0.05. The most optimal results are marked with *.

Figure 11
A. Fitting probability density curves and cumulative probability density curves of the annual maximum wind speed series from P1 to P4; B. Fitting probability density curves and cumulative probability density curves of the annual maximum wind speed series from P5 to P7
Table 5
Different return values of extreme wind speeds (m s−1) based on Gumbel and P-III distributions from P1 to P7 for 50-year and 100-year return periods; higher extreme speeds are marked with *
| Points | Distribution | 5-year | 10-year | 25-year | 50-year | 100-year |
|---|---|---|---|---|---|---|
| P1 | Gumbel P-III | 22.62 22.59 | 23.17 23.39 | 24.32 24.27 | 25.18* 24.85 | 26.03* 25.38 |
| P2 | Gumbel P-III | 22.35 22.47 | 23.41 23.27 | 24.75 24.15 | 25.74* 24.73 | 26.73* 25.26 |
| P3 | Gumbel P-III | 22.43 22.86 | 23.33 23.73 | 24.48 24.68 | 25.33* 25.30 | 26.17* 25.88 |
| P4 | Gumbel P-III | 21.89 22.16 | 22.73 22.97 | 23.78 23.87 | 24.57* 24.49 | 25.34* 25.06 |
| P5 | Gumbel P-III | 21.57 21.78 | 22.45 22.58 | 23.56 23.49 | 24.38* 24.11 | 25.20* 24.68 |
| P6 | Gumbel P-III | 21.65 21.76 | 22.62 22.58 | 23.85 23.52 | 24.76* 24.16 | 25.67* 24.76 |
| P7 | Gumbel P-III | 22.26 22.71 | 23.26 23.66 | 24.52 24.71 | 25.46* 25.40 | 26.39* 26.03 |

Figure 12
Spatial distributions of extreme wind speeds in 50-year and 100-year return periods based on the P-III distribution function