Presentation Description: Wind stilling, broadly defined as a reduction of global average surface wind speed over land, has reappeared in the media recently raising concerns, and perhaps a certain level of confusion, about future wind resource potential in different parts of the World. It is clear then, that screening and understanding this phenomenon is of paramount importance for the wind industry. In spite of a large body of research, however, several questions remain contentious: Are the inferences about stilling robust? Or do they depend on the source of the data? Is the observed decline in average wind speeds a steady trend or part of a cycle ? Can we infer a trend from a short time series of observations? Are the cycles driven by known internal modes of climate variability such as El Nino or the North Atlantic Oscillation? What can we say about wind stilling under climate change ? In this talk we address these questions by analysing wind indices derived from extended ERA5 (1950-present) and WRF ERA5 (1980-2020) time series for selected sub-regions in US and Canada, where the wind potential is significant. We study the contemporaneous wind patterns, and identify links to the relevant internal modes of climate variability. Downscaled CMIP5 models’ projections are analyzed to estimate the impacts of climate change on the selected wind indices.
Methodology: The presentation will start with a question to the audience and will include data drive visuals and animations