HR: 1340h
AN: H33B-1390    [Abstracts]
TI: Drought Analysis in Northeastern Argentine
AU: * Garcia, N O
EM: nogarcia@fich.unl.edu.ar
AF: Universidad Nacional del Litoral - Facultad de Ingenieria y Ciencias Hidricas, C.C. 217,Ciudad Universitaria, Santa Fe, SF 3000 Argentina
AB: The objetive of the present work was analyze the occurrence of droughts in the context of the climatic variability, in a wide region of the Argentinean territory that encompass the six provinces of the northeastern (Misiones, Corrientes, Entre R¡os, Santa Fe, Chaco and Formosa). In order to define the droughts a decilic analysis of the monthly precipitation records was used, and the temporal and spatial variability were analyzed with Spectral Analysis of the composite dry year (From January of the year of droughts onset until December of the following year), this period contain the complete hydrologic dry-year. It was observed that the occurrence of annual droughts change along the last century, verifying an average of one drought each three years up to 1969 and one drought each five year from 1970. From the point of view of the relative amount of fallen water, it was observed that the extreme dry periods take place in autumn, winter and spring and weak dry period during the summer or to along the complete hydrologic year. The spatial and temporal behavior of the dry periods showed that the composite dry-years are more significant in amplitude and phase than composite LA NI¥A years. So much the rains of summer like the winters droughts accentuate the second harmonic amplitude, that contains information of the amount of fallen water and also represent the annual cycle of the precipitations, while the droughts of summer attenuate it. The harmonic dials in the analyzed region showed that the second spectral component is the most significant, while the first component indicates their relationship with the region EL NI¥O, in the Equatorial Pacific Ocean. The results indicate a regional homogeneous characterization regarding the first harmonic in the north, the same as the area center-eastern, while the southwest and south area has a behavior with characteristic very particular characteristics during the dry events (second harmonic not significant).
DE: 1800 HYDROLOGY
DE: 1812 Drought
DE: 1833 Hydroclimatology
SC: Hydrology [H]
MN: Fall Meeting 2005