Breakpoints in annual rainfall trends over Córdoba, Argentina

A DE LA CASA; OLGA NASELLO;

ATMOSPHERIC RESEARCH

ELSEVIER SCIENCE INC

Año: 2009 vol. 95 p. 419 - 427

0169-8095

Abstract:Long-term rainfall variability in Córdoba Province of Argentine has been studied identifying thebreakpoints which show a sudden transition from one period to another with a quasi-linear trend. All rain gauges operated by the "Servicio Meteorológico Nacional" (SMN) of Argentina in the Córdoba Province, Argentina, were used. The analyzed periods extend from 1930 to 2006. One of the studied station, Córdoba Observatorio station, has reliable rainfall data since 1873. In this case, the1930-2006 period was evaluated to homogenize the time series, and the 1873-2006 one was investigated to analyze series length influence with respect to piecewise linear trends produced. Analyzing only one breakpoint in all the series, in the north area of the region it is observed a trend change from a negative to positive at the 1950´s , whereas in the other areas, the opposite change occurs at the 1970´s.The square residual sum obtained with the partial trend method was compared to that produced by the traditional method. This comparison showed how the multiple trend method allows determining regional changes for a given climatological variable