Variabilidad, tendencia y eventos extremos en los rendimientos agrícolas a nivel de partidos en la provincia de Buenos Aires

Climate variability is the main determinant of fluctuations in the productive and economic results of agriculture. Extreme events are expected to occur with greater frequency and intensity in the future. In this scenario, the effects of climate variability on agricultural production are of special interest. This study analyzes the time series of yields at the county level of the main crops in the province of Buenos Aires, in the period 2000/01-2020/21. The trend and occurrence of extreme values ””of wheat, corn and soybean yields are identified. The frequencies of extreme values ””are related to the phases of the ENSO -El Niño-Southern Oscillation phenomenon, for each crop year. Yields show significant positive trends in 78%, 46% and 30% of the counties for wheat, corn and soybean, respectively. There is a significant relationship between the frequencies of extreme yield values ””and the ENSO phases, this relationship being more important in summer crops. In particular, there is a relative frequency of extremely low or very low yields of 38 and 41%, in second consecutive La Niña crop years, for corn and soybean, respectively. While the frequencies of extremely low or very low yields in neutral or El Niño crop years are between 0% - 3%. Regarding the economic value of production, the differences between obtained vs. expected values, accumulated in the period, are positive values of +3285 and +872 million USD in “El Niño” years for the north and south regions, respectively, and negative values of -3387 and -388 million USD, in “La Niña” years for both regions, respectively. The results provide evidence on the potential value of ENSO-based seasonal forecasts for agriculture. However, it is necessary to deepen the analysis of the effects of ENSO and other seasonal phenomena on yields. It is also necessary more information about the attitudes of the farmers in the Pampas and the different management practices that can be adjusted based on these forecasts.