Climatic and hydrological variations during the last 117–166 years in the south of the Iberian Peninsula, from spectral and correlation analyses and continuous wavelet analyses

The most complete historical series of instrumental data available, spanning more than a century, on rainfall, temperature and outflow of a karst spring obtained from gauging stations in the south of the Iberian peninsula were analysed by means of spectral and correlation analyses and continuous wavelet analyses. Annual periodicity of the rainfall and temperature distributions was constant over more than 100 years, although weaker (6-month) periodicities have also been observed, as well as rainfall and temperature periodicities of 5 and 2.5 years, which have also been recorded in other areas of Europe. These multiannual scale components can be explained by climatic variations or effects described in the literature in connection with the North Atlantic Oscillation (NAO) and are likely to be the same as the climate variability at decadal to annual scale detected in several proxy data from geological records. No long-term trends in the distribution of precipitation and temperature were detected.