Probability of occurrence of harmful and favorable monthly minimum and maximum air temperatures for agricultural crops in Rio Grande do Sul

Abstract

The objectives of this work were to verify the adjustment of time series of monthly minimum (Tmín) and monthly maximum (Tmáx) air temperatures, in the State of Rio Grande do Sul, to the normal, log-normal, gamma and weibull probability distributions, to determine probabilities of occurrence and prepare maps with the interpolation of isolines. The Kolmogorov-Smirnov test was applied to 216 time series of Tmín and 216 time series of Tmáx (18 cities × 12 months). Based on the normal distribution, values of Tmín were determined, whose probability of occurrence of Tmín less than or equal to this value is 90%, and values of Tmáx, whose probability of occurrence of Tmáx greater or equal to this value is 90%. From these values, maps were prepared with interpolation of isolines with a difference of 0.5ºC. The Tmín and Tmáx data adjust the normal, log-normal, gamma and weibull distributions, showing better adherence to the normal distribution. The maps with the isolines are useful to verify the probability of occurrence of harmful or favorable Tmín and Tmáx for agricultural crops in the State of Rio Grande do Sul, during the months of the year.