Drought indicators revisited: the need for a wider consideration of environment and society

Abstract

Abstract[Drought indicators are proliferating, but with little consideration of which are most meaningful for describing drought impacts. A number of recent reviews compare different drought indicators, but none assess which indicators are actually used in the many operational drought monitoring and early warning efforts, why they were selected, or whether they have been 'ground-truthed', i.e., compared with information representing local drought conditions and/or impacts. Also lacking is a comprehensive assessment of the state of monitoring of drought impacts. To help fill this gap, we combine a review of drought indicators and impacts with a survey of 33 providers of operational drought monitoring and early warning systems from global to regional scales. Despite considerable variety in the indicators used operationally, certain patterns emerge. Both the literature review and the survey reveal that impact monitoring does exist but has rarely been systematized. Efforts to test drought indicators have mostly focused on agricultural drought. Our review points to a current trend towards the design and use of composite indicators, but with limited evaluation of the links between indicators and drought impacts. Overall, we find that much progress has been made both in research and practice on drought indicators, but monitoring and early warning systems are not yet strongly linked with the assessment of wider impacts on the environment and society. To understand drought impacts fully requires a better framing of drought as a coupled dynamic between the environment and society.]

Drought in a human-modified world: reframing drought definitions, understanding, and analysis approaches

“…uio.no/edc/droughtdb/) collect and categorize textual drought impact reports, whereas Lackstrom et al (2013) and others suggest the development of a more targeted impact monitoring. A survey of operational monitoring and early warning systems by Bachmair et al (2016a) found that many regional systems do monitor impacts, however, not in a systematic way and thus they do not consider them for the drought warning and other management in a quantitative manner. Hence, impact monitoring is an important starting point for improvement.…”

“…Figure 6 gives an overview of the different methods. The most widely adopted approach to relate drought indicators to impacts is to link commonly used hydrometeorological drought indicators to agricultural yield (Lobell et al, 2008;Vicente-Serrano et al, 2012Bachmair et al, 2016a). Most of these studies are based on correlation and as summarized by Stagge et al (2015a), thus are useful for screening relationships, but they measure the response of a variable, such as crop yield, across its entire range of values including typical or even productive years.…”

Greater Temperature and Precipitation Extremes Intensify Western U.S. Droughts, Wildfire Severity, and Sierra Nevada Tree Mortality

“…However, comparisons of spatiotemporal climate patterns over the formation, progression and termination of regional, multi-year WUS droughts remain scarce. Recent work offers substantive comparisons of droughts and effects, but these and similar studies can be spatially or temporally limited, or use indicators unsuited to assessing ecological impacts or longterm trends (Bachmair et al 2016, Robeson et al 2016, Ge et al 2016, Asner et al 2016.…”

“…Limitations in drought metrics are unavoidable: severity is subjective beyond "dry" (Alley 1984, Bachmair et al 2016. Stakeholder-specific thresholds identifying extreme aridity must be established, as drought indicators useful for one application may not be relevant to another (Hayes et al 2005, Stephenson 1998, Steinemann 2014, Bachmair et al 2014.…”

Rain Gauges to Range Conditions: Collaborative Development of a Drought Information System to Support Local Decision-Making

“…This work contributes to a larger conversation among researchers, natural resources managers, and decision-makers globally about how to best conceptualize drought so that it can be better planned for and the impacts better mitigated. A recent review by Bachmair et al (2016) points to a significant gap between how drought is characterized by conventional drought indicators and how drought is experienced locally. They note that ''citizen science initiatives and other social learning approaches that explore drought framing.…”