Decision-relevant metrics for regional hydroclimate phenomena

A growing group of climate adaptation practitioners is seeking actionable information about present and future climate change to support their decision-making processes. However, not all regional scale climatic phenomena that are of interest to practitioners are represented well in the models and datasets available today. As the scientific and technical methods for producing climate information evolve, a means of tracking progress toward meeting practitioner needs could play a critical role in guiding new scientific efforts (e.g. model parameterization improvements or the development of new downscaling methodologies) in addition to guiding appropriate use of existing data sets.

Here we describe an iterative stakeholder engagement process with water managers in four case study basins across the US aimed at identifying decision-relevant metrics for regional hydroclimate phenomena. Stakeholders have engaged with atmospheric and hydrologic modeling experts over the course of 2 years through workshops, focus group discussions, and interviews, resulting in several metrics that differ in quality from the typical metrics applied to evaluate regional hydroclimate model fidelity. The team has also identified particular spatial and temporal scales over which the metrics are of interest. The science team has selected a handful of these metrics to evaluate in detail across a range of observational and model-based datasets. We present results here from the broader engagement effort as well as specific insights related to snow accumulation and melt dynamics and extreme precipitation.