Background

We propose having High Resolution Modeling (HRM) activities conducted in the continental U.S. (CONUS), along with regions of central western Canada, function as the glue between the various science research focus areas mentioned below. In addition, we envision an open and accessible community data policy with regards to sharing observational data, model output, etc. This is the best way forward for a successful endeavor and particularly for entraining and supporting early career researchers (ECRs).

GOALS:

The overarching goal of the US Regional Hydroclimate Project (USRHP) is to determine how fresh water availability will change over the coming decade and to understand the impact of these changes on society.

Four main research questions that can guide the USRHP are:

1. Which characteristics of precipitation affect water availability, and how are they changing?
2. What are the roles of land surface processes and human water use in affecting water availability?
3. How can new observational data streams be developed to detect and attribute changes in water availability, and constrain climate change projections? What new observations and observational strategies are needed?
4. How predictable are the key drivers of water availability on subseasonal to decadal time scales in CONUS? What are the scales of useful predictability for different types of water availability and processes?

RESEARCH FOCI:

We envision the following foci under this umbrella:

1. High–resolution coupled climate modeling
2. Evaluation of Climate Projections & Assessments of Climate Impacts
3. Mountain (Terrain) Hydrology
4. Observations for process-level understanding and model evaluation and refinement
5. Ecosystem Science
6. Water-Energy-People Nexus
7. Socio Economic Aspects
8. Policy Implications – governance and legislative issues, particularly on implementation and application of the science.

MECHANISMS (for achieving USRHP goals):

1. Development a web-based platform–any field campaign component should precede the core modeling activity:
   1. Distribution of a common set of boundary forcing over agreed-upon target domains and time periods;
   2. Collection and Distribution of associated participant outputs; and
   3. Distribution of associated verification data and benchmark tests (e.g., GLASS-PALS).
2. Pilot studies
3. Workshops, seminars
4. Inventory and survey of existing observing systems that meet requirements or can be leveraged to do so.