ABSTRACT
Drought and water scarcity are frequently used interchangeably in public discourses about water and water management. This is in part because defining drought precisely can be difficult. Droughts are a meteorological phenomenon where water availability is below an ‘average’, calculated using data on historic trends. However, specific definitions vary widely by sector and region and droughts tend to develop slowly under complex meteorological, hydrological and temporal scales that can be very location specific. The imprecision of drought definitions can lead to confusion and inaction on the part of water managers and policy-makers and can also lead to a misuse of the term ‘drought’ to describe situations of water scarcity (Scott et al., 2013). Long episodes of reduced precipitation and more frequent extreme climatic events are contributing to increasing uncertainty and vulnerability to water supply, including in the north-west of Mexico (IPCC, 2012). Climate change projections for reduced precipitation and severe drought in this ‘already water-scarce region’ are expected to cause ‘troublesome consequences’ (Wilder et al., 2012).
