Future trends in wind resources and their consistency in the Indian sub-continent

We use the latest Coordinated Regional Dynamical Experiment regional climate models over South Asia at 0.22 degrees grid spacing (WAS-22) under two Representative Concentration Pathways scenarios (RCP 2.6 and RCP 8.5) to evaluate their performance against their predecessor at 0.44 degrees grid spacing (WAS-44) and investigate the impact of climate change on future wind resources in the Indian sub-continent. The comparison of WAS-22 with the previous WAS-44 regional climate models looks at their ability to reproduce annual and seasonal wind speed climatology and trends with respect reanalysis datasets and finds that WAS-22 models achieve the best results. Hence, we use WAS-22 models as a source of climate information, correlate them to local station measurements and wind farm operation data at three sites in the study domain. We then estimate future annual and seasonal wind trends in the Indian sub-continent. Our findings on future trends suggest increasing annual wind speeds in the north-west (+ 0.04 m/s per decade (+/- 8%)), the center (+ 0.03 m/s per decade (+/- 11%)) and the east (+ 0.02 m/s per decade (+/- 19%)) of the Indian sub-continent under the RCP 8.5 scenario at the end of the century, with changes occurring more substantially during the last 30 years of the century. The results project future perturbations during the pre-monsoon season occurring throughout India and trends with the highest magnitude concentrated during the monsoon season. An additional contribution of this investigation is a decision-making tool enabling the quantification of the spatio-temporal consistency of wind trends using a structure-function.