The iCOLT climate service: Seasonal predictions of irrigation for Emilia‐Romagna, Italy

Abstract

Abstract Emilia‐Romagna is a region of Northern Italy whose land use is mainly devoted to agriculture, especially over the plain area. Since the region is characterized by summer water shortages and recurrent drought conditions, a summer irrigation water demand forecast system has been developed, operating both at regional and Land Reclamation and Irrigation Board levels. Remote sensing crop detection is used in combination with a soil water balance model as a monitoring tool in support to water management and to optimize the use of available water resources. These instruments are also integrated with operational calibrated probabilistic seasonal forecast products currently based on Copernicus Climate Services, in order to evaluate summer irrigation water needs in advance in support to decision‐making by water managers. Results obtained using this prediction system are characterized by a significant forecast skill. The sources of the predictability of this system are specifically evaluated, showing that the correct representation of crop geographical distribution is crucial for the ability of the system to capture spatial variability in irrigation demand. Furthermore, the system forecast skill is mostly due to the use of an empirical model to assess the hypodermic water table depth initialized by means of the observed meteorological data of the months before the beginning of the summer season. Finally, calibrated probabilistic seasonal predictions also contribute to a minor extent to the good performance of the system as a whole.

Keywords

• crop development model
• early crop map
• hypodermic water table
• irrigation planning
• probabilistic seasonal forecasts
• remote sensing detection