Resumen

FERNANDEZ LONG, María Elena; MURPHY, Guillermo  y  TORTEROLO, María Karina. Sistemic frost risk index (SFRI). Agronomía Trop. [online]. 2008, vol.58, n.1, pp.65-68. ISSN 0002-192X.

The aim of this study is to present the fundamentals and methodology of the SFRi. Hourly temperatures of five observatories for the period 1991-2003 were used to calculate the duration of frosts and analyse their relationship with the minimum temperature. Daily minimum temperatures from the period 1964-2003 were used for the development of the SFRi. We assume that late frosts will be more dangerous the sooner the phenology of the crop or the more delayed the frosts, also the greater their intensity, length and frequency. The IRiSH integrates all these variables directly or indirectly. We describe, as an example, the empirical functions developed for calculating the index for wheat cultivation. The result is a versatile index, applicable to different crops, which takes into account the main variables that determine the level of danger from frosts. It allows to monitor frosts risk during the year, and to examine their inter-annual variability, temporal trend and special distribution. With annual averages for many years it also allows for the climatic characterization of frosts risk.

Palabras clave : heladas; peligrosidad; variabilidad.