Evaluation of an Integrated Seasonal Forecast System for Agricultural Water Management in Mediterranean Regions

摘要

The Euro-Mediterranean Center on Climate Change (CM-CC) seasonal forecasting system, based on the global coupled model CMCC-CM, performs seasonal forecasts every month, producing several ensemble integrations conducted for the following 6 months. In this study, a performance evaluation of the skills of this system is performed in two neighbouring Mediterranean medium-small size catchments located in Southern Italy, the Crati river and the Coscile river, whose hydrological cycles are particularly important for agricultural purposes. Initially, the performance of the system is evaluated comparing observed and simulated precipitation and temperature anomalies in the irrigation periods of the years 2011-2017. Forecasts issued on April 1st (i.e., at the beginning of the irrigation period) are evaluated, considering two lead times (first and second trimester). Afterward, the seasonal forecasts are integrated into a complete meteo-hydrological system. Precipitation and temperature provided by the global model are ingested in the spatially distributed and physically based In-STRHyM (Intermediate Space-Time Resolution Hydrological Model) model, which analyzes the hydrological impact of the seasonal forecasts. Though the predicted precipitation and temperature anomalies are not highly correlated with observations, the integrated seasonal forecast for the hydrological variables provides significant correlations between observed and predicted anomalies, especially concerning mean discharge (>0.65). Overall, the system showed to provide useful insights for agricultural water management in the study area.