R. Magno, L. Angeli, M. Pasqui, M. Chesi, L. Rocchi, F. Zabini. "Development of a system for monitoring and forecasting drought events over Tuscany region". Proceedings del XIII International Conference on Environmental Science and Technology (CEST 2013).  ISSN 1106-5516;   ISBN 978-960-7475-51-0.

Abstract:

Drought is a recurrent feature of climate and can affect areas with different climate regimes and human activities. Its impacts depend on the duration, intensity and extent of precipitation deficiency and water demand for several purposes. Due to the complexity of this phenomenon, it is crucial to analyze both current conditions and evolution of a drought event in order to provide accurate, timely and affordable support for policy setting and impacts management. In this perspective the LaMMA Consortium of Tuscany Region and the IBIMET-CNR Institute are developing a comprehensive operational system for quasi-real time drought monitoring and medium-long time forecasts in Tuscany region (Central Italy), with the aim to deliver periodical, geo-referenced information about areas affected by an increasing reduction of available water resources. The monitoring part of this system consists of a coupled rainfall-based and satellite-derived set of indices suitable for our region and selected taking into account data availability. This system allows the assessment of vegetation moisture and temperature conditions at different spatio-temporal scales. An analysis of vegetation performances related to temperature and moisture stress is made throughout the Normalized Difference Vegetation Index (NDVI) profiles anomalies and the Vegetation Health Index (VHI), derived from the Terra-Moderate Resolution Imaging Spectroradiometer (MODIS) products, available since 2000 and updated each 16 days. These indices are selected in order to enhance the climate-based Standardized Precipitation Index (SPI) and Effective Drought Index (EDI), which provide multiple time scale drought occurrence and duration. In this paper a multi-temporal NDVI profile of deciduous Tuscan forests is used as monitoring example of seasonal growth variations related to extreme climate events. For the forecasting part of the system the SPI, elaborated from a daily E-OBS (Ensamble Observational) gridded data set over the whole Europe, provides the basis for seasonal outlooks of drought evolution. Forecasts of the next 1-3 months follow a physically-based statistical approach based on an “adaptive multi-regressive method” that takes into account potential predictors among a list of physical atmospheric indices and Sea Surface Temperature (SST) anomalies. Information about current condition related to the last 16 days available is delivered on the LaMMA Consortium web site and uploaded on an Open Source WebGIS platform. Finally, monthly bulletins furnish a more detailed description of drought evolution throughout an analysis of the indices in the last 30 days and a forecast of the next 1-3 months. This comprehensive monitoring and forecasting system, can become a timely and stand-alone multi-purpose environment to share information potentially useful to final users for managing drought-related emergencies as crop yields losses, forest fires and water resources reduction.