A Shift in the Wind Regime of the Southern End of the Canary Upwelling System at the Turn of the 20th Century

In this study, we make use of historical wind direction observations to assemble an instrumental upwelling index (DUI) at the southern end Canary Current Upwelling System. The DUI covers period between 1825 and 2014 and, unlike other indices, it does not rely neither in speed nor reanalyzed data. sense, can be regarded as index. Additionally, avoids suspected bias toward increasing documented previous research. Our results indicate that frequency alongshore winds west coast Africa 10°N 20°N measured by is significantly related with stress therefore intensity region. presents a significant variability both interannual decadal timescales. We have found any trend for 20th century. However, when entire length series considered, large shift more frequent evidenced result several decade-long fluctuations which took place late 19th century beginning This fact would imply change System should occurred turn