Resumen

VERGARA, Graciela Teresa; CASAGRANDE, llermo Alberto  y  ARNAIZ, Juan Pablo. Agroclimatic characterization of droughts (1970/2005) in three localities of la Pampa, Argentina. Agronomía Trop. [online]. 2008, vol.58, n.1, pp.77-80. ISSN 0002-192X.

Droughts, which are a function of the spatial and temporal variablity and total amount of rainfall, have significant negative effects on socioeconomic aspects of a country. Palmer’s Drought Severity Index was calculated for characterize droughts at three sites located in the agricultural zone of La Pampa Province, General Pico, Santa Rosa y Guatraché for the period 1970-2005. During the period of analysis, the frequency of humid events was greater than the frequency of dry or normal periods in the three sites. General Pico had the lowest freqency of drought, followed by Guatraché and then Santa Rosa. General Pico had the highest freqency of humid episodes, followed by Santa Rosa and Guatraché. Guatraché has greater frequency of normal months than Santa Rosa and General Pico. The highest frequencies of drought intensity correspond to category weak in the three sites. At General Pico neither severe nor extreme droughts are registered, whereas in Santa Rosa and Guatraché only extreme droughts did not occur. In General Pico, Santa Rosa and Guatraché the month with highest drought frequency are August, October, and November respectively. The months with lowest frequency of droughts are January and November in General Pico, and January in Santa Rosa and Guatraché.

Palabras clave : Sequía; episodio húmedo; episodio seco; índice de severidad de sequía.