Following the 1995 drought, the Drought Vigilance and Alert Program (PVAS—Programa de Alerta e Vigilancia de Secas) was developed (between 1995 and 1998) by INAG, the National Water Institute, an institution that was incorporated in the Portuguese Environmental Agency (APA) in 2012, which became the national Portuguese Water Authority. The PVAS was used to monitor the 2004-2005 and 2012 drought events. The PT DMP proposal calls for the use of PVAS, including some modifications such as the reinforcement of the piezometer monitoring network. Through PVAS, it will be possible to identify long-duration drought and water scarcity events and impacts, based on information on common hydrometeorological variables: precipitation, river flows and water storage in reservoirs, and aquifers. From that information, an evaluation is carried out in four periods of the hydrological year (end of January, March, May, and September), in order to assess exceptional circumstances due to drought.
Monthly reports on common meteorological information (prepared by the Portuguese Meteorological Institute, IPMA) that may be relevant for assessment of drought conditions, such as SPI and PDSI (Palmer drought severity index), are made public at the GPP (coordinator of CSAC's working group) website. The PT DMP proposal also foresees monitoring (in normal and drought conditions) of rain-fed agriculture and extensive livestock production indicators.
According to the PT DMP proposal, the monitored variables are the basis to assess agrometeorological and hydrological drought status, which in turn is associated with the four levels for drought conditions: normal, prealert, alert, and emergency. Each drought level may be related to certain drought measures. For example, the alert level may be related to the implementation of mitigation measures, such as restrictions in water uses (APA 2016). It should be noted that DMP PT overall monitoring procedures (action plan) are not yet fully implemented.
Currently, in Portugal, some rain-fed agricultural and extensive livestock production activities are monitored, and the results are made available (by the SIMA and RICA systems—in Portuguese, respectively, Sistema de Informa^ao de Mercados Agricolas and Rede de Informa^ao de Contabilidades Agricolas). According to the PT DMP proposal, the information obtained from these current monitoring systems could be used to evaluate drought impacts. This kind of information was used by CSAC's advisory technical working group when evaluating the drought situation during the 2014/2015 meteorological (prealert) drought event.