Future Projections for Wind, Wind Shear and Helicity in the Iberian Peninsula

Wind is among the most important climatic elements. Its characteristics are determinant for a wide range of natural processes and human activities. However, ongoing climate change is modifying these characteristics, which may have important implications. Climatic changes on wind speed and direction, wind shear intensity, and helicity, over the 21st century and for 26 cities in the Iberian Peninsula, under the Representative Concentration Pathway (RCP) 8.5 anthropogenic forcing scenario, are assessed. For this purpose, the Weather Research and Forecasting (WRF) model was used, with initial and boundary conditions being obtained from simulations with the Max Planck Institute for Meteorology Earth System Model (MPI-ESM-LR) climate model and ERA-Interim reanalysis. Quantile-quantile bias correction was applied to the simulated data prior to subsequent analysis. Overall, the results hint at a reduction in the intensity of both near-surface and 850 hPa (approx. 5%) wind in the future. Nevertheless, for the 300 hPa level, a decrease in summertime wind speed is accompanied by a slight increase in the remaining months. Furthermore, significant increases in the number of occurrences of extreme wind events were also identified, mainly in northwestern Iberia. For wind shear, an intensity increase is projected throughout most of the year (approx. 5% in the upper quantiles), mainly in southwestern Iberia. Helicity is also projected to undergo a strengthening, mostly in summer months and over southwestern Iberia, with greater emphasis on events of longer duration and intensity. This study highlights some important projected changes in the wind structure and profile under future anthropogenic forcing. This knowledge may support decisions on climate change adaptation options and risk reduction of several major sectors, such as energy and aviation, thus deserving further research.