Author / Editor: Manuel González, Almudena Fontán, Ganix Esnaola and Victoriano Valencia (AZTI-Tecnalia)
Content In this study, a novel approach is used to analyse the long-term variability of air temperature in Igeldo (1928-2009) and Hondarribia (1971-2009), sea surface temperature at the Aquarium of San Sebastián (1947-2009), and sea level datasets from Saint Jean de Luz (1964-1997) and Santander (1943-2004).
This mathematical technique, known as the Kolmogorov-Zurbenko Adaptive filter in honour of the authors, was developed specifically to study long-term trends and to detect abrupt breaks in time-series induced by natural variability or by instrumental systematic errors, regulatory changes, improvement of sanitation systems, the impact of a medicine or the effect of an insecticide, etc.
This paper analyses the changes observed in atmospheric and sea surface temperatures and sea level in the southeastern corner of the Bay of Biscay. Some of the abrupt discontinuities detected in air and sea temperatures and mean sea level time-series may be explained by climatic changes at a global scale (the cold period of the 70’s associated with the Great Saline Anomaly or an increase in atmospheric temperature of about 1.2 ° C during the 80’s)