Assessment of the spatial distribution of continental-oceanic climate indices in the Iberian Peninsula

摘要

Oceanity and continentality strongly influence the climate of a region. Aiming at understanding these influences on the Iberian Peninsula climate, the spatial distributions of precipitation, air temperature and five climatic indices are analysed during the period 1901 and 2012 and in three sub-periods (1901-1940, 1941-1980 and 1981-2012). This study focuses on investigating the continental and oceanic characteristics of the Iberian climate by using the Conrad-Pollak and Johansson Continentality Indices, as well as Kerner and Marsz Oceanity Indices. Gridded precipitation and air temperature data sets are used on a monthly basis. Results reveal hyper-oceanic (maritime) characteristics in the northernmost portion of Iberia, continental in the inner region comprising Extremadura, Castile-La Mancha and Andalusia, and maritime characteristics in between. It is worth noting that within these regions the continental (maritime) characteristics become stronger (weaker) between 1981 and 2012. Statistically significant linear trends show an increase in both temperature (2-4 degrees C) and on continental influences in the northwestern and southeastern regions of Iberia for the entire period. Statistically significant correlations are also found between the Johansson Continentality Index and both Conrad-Pollak and Marsz Oceanity Indices at a 95% confidence level, revealing a good agreement of results among these indices.