“…Methods such as principal component analysis (PCA), widely employed in several environmental areas (Rojo-Nieto et al, 2013;Terrado et al, 2006), partial least squares-discriminant analysis (PLS-DA), artificial neural networks (ANNs) (Álvarez-Guerra et al, 2010), cluster analysis (Chen et al, 2012) or positive matrix factorisation (PMF) (Jang et al, 2013) are presented in the literature as a complement to classic univariate statistics, often unveiling concealed environmental information (Álvarez-Guerra 4 et al, 2010;Chen et al, 2012;Gredilla et al, 2013;Jang et al, 2013;Navarro et al, 2006). Canonical correlation analysis (CCA) is an exploratory method designed to study the relationship between data matrices containing different information within the same samples, which make it especially attractive in the field of environmental monitoring (Amigo et al, 2012;Galloway et al, 2002). This allows one to link the behaviour of variables of different nature that, otherwise, would be very difficult to assess (e.g.…”