versión On-line ISSN 1850-468X
ARANEO, Diego C et al. Characterization Of Summer Soundings From Northern Mendoza By Principal Components Analysis And The Obtaining Of A Convection Index. Meteorologica [online]. 2011, vol.36, n.1, pp. 31-47. ISSN 1850-468X.
The Principal Components Analysis was used to characterize the summery North Mendoza rawinsondes, evaluating their capacity to identify patterns associated to the convection occurrence and defining an instability index. It was selected 326 cases, building an entry matrix with the temperature and dew point temperature anomalies for the standard levels between 850 and 300 hPa. The analysis showed 6 significant components that explain more than 91% of variance. Therefore, 12 patterns were obtained, which represent different atmospheric conditions. The main correlations between the patterns and convection (C) and non convection (NC) cases were obtained for the components 6, 2, 4 and 3. The relatively wet environments with a strong gradient of T at mean and high levels would favour the convection, while it is inhibited with dry layers in mean and high levels, and weak gradients of T in low layers. The C/NC index can be estimated by a logistic multiple regression dependent to the component loadings, with a correlation of 0,5, determining a stability/instability index calculable from the T and Td profiles and it depends on the climatological features of the region. The index showed an efficiency of 72%.
Palabras llave : North of Mendoza; Rawinsondes; Convection; Instability index.