Wind climatology of Toronto based on the NCEP/NCAR reanalysis 1 data and its potential relation to solar activity

Abstract

This study represents a comprehensive analysis of the wind climatology for the Toronto area based on the daily National Center for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) reanalysis 1 data extracted for the period 1948–2014. The research is focused on investigating wind speed and wind direction distributions, long-term wind trends, and low-frequency wind spectrum. The results are given at the sigma-995 level. Westerlies are active in about 50% of the time in year. The strongest winds are coming in from 240° direction and the windiest seasons are winter and fall, followed by spring. A trend analysis shows that statistically significant and positive wind speed trends are present for both the omnidirectional mean annual wind speeds as well as for the winds associated with the most prevailing wind directions. Winter and fall winds had positive trends whereas negative wind speed trends in the summer and spring seasons are negligible. The spectral analysis of wind speed time series shows three distinguished peaks: (1) 2–4.5 days, (2) yearly, and (3) 11-year peak. The lowest frequency peak in the wind speed spectra is linked to the solar activity through the cross-correlation analysis and the relationship is discussed in details.