• HydroHUB and CHyMP

The Community Hydrologic Modeling Platform, which is being pursued by CUAHSI under the acronym CHyMP [Famiglietti et al. 2009], is proposed as an effort to develop the next generation of simulation codes. CHyMP forms a synergistic companion to HydroHUB. The 2nd CHyMP workshop identified the evaluation of existing modeling platforms as a key component of the CHyMP development process. We propose that this evaluation could be conducted by installing existing platforms on HydroHUB. This will ensure the platforms run on the same hardware and it will ensure a uniform access to the platforms by the participants of the evaluation.

An early product of the CHyMP program is envisioned to be the development of several prototype Modeling Platforms. These new prototypes would be deployed on HydroHUB for testing and evaluation. It would be possible, for example, to provide immediate access to the CHyMP prototypes to anyone in the hydrologic research community through HydroHUB. Once a full-scale CHyMP has been developed, HydroHUB will be ready to facilitate access to CHyMP on the most powerful computers available. The CHyMP project will also benefit from the ability to run real-time seminars that will make learning CHyMP software quicker and easier.

HydroHUB will speed the development, improve the performance, and make CHyMP easier to access and learn. HydroHUB will support CHyMP, but it is important to recognize that the CHyMP project itself will be a separate software development effort that is outside of the scope of HydroHUB.

• HydroHUB and CSDMS

HydroHUB and CSDMS share the common goal of advancing discovery by improving computational infrastructure available to scientists interested in surficial earth processes. The CSDMS strategy for achieving this goal is significantly different than that proposed by HydroHUB. CSDMS is focused on developing new software tools that will expand computational capabilities, whereas HydroHUB will improve access to existing codes and computer resources.

Detailed discussions with the CSDMS team during the development of this proposal identified the potential for important synergies. HydroHUB could benefit from including software innovations developed at CSDMS, whereas CSDMS could benefit from the ability to run their models through a cutting-edge graphical interface implemented on HydroHUB. CSDMS has begun to compile a repository of models, which already includes some hydrology models. HydroHUB would also require a repository of models, some of which would be of interest to CSDMS users. We propose to collaborate with CSDMS engineers to develop a master repository of models that will benefit both projects.

Two members of the CSDMS technical staff will be part of the HydroHUB site team and will collaborate with us on building and operating the site. Scott Peckham, lead software engineer at CSDMS, will be on our Steering Committee. Further details about CSDMS involvement in the proposed project are in the Management Plan, Section 8.

• HydroHUB and WATERS Network

The WATERS Network is a major initiative to better predict and manage the behavior of water, its nutrients, contaminants, and sediments, everywhere in the U.S. This program currently includes 10 Test Bed sites (www.watersnet.org/wtbs/) where important data are being gathered, and models are being calibrated, tested and refined to predict hydrologic processes.

We propose that models from WATERS Test Beds be included as part of the Model Gallery. This will provide the capability for investigators to access and run from any web browser the latest calibrated models from Test Bed Sites. In this way, the community will quickly have access to not only the data from Test Bed Site, but also from the predictive capability that these data enable. Input files and results from hydrologic models calibrated to areas outside of WATERS Test Beds will also be accessible through HydroHUB. This provides a convenient vehicle for using insights from Test Beds to improve simulations in similar areas. Perhaps more importantly, it enables the growth of a predictive capability beyond the limits of existing Test Beds. The ultimate goal of WATERS Network is to improve prediction of water-related processes across the U.S. and HydroHUB will provide cyberinfrastructure that will help reach this goal.

• HydroHUB and HIS

The Hydrologic Information System is transforming the way hydrologists access data, and we propose that HydroHUB will provide a similar transformation by improving access to models. However, models are of limited use without data to calibrate them, so HydroHUB will leverage the power of HIS to improve the capabilities it provides to users. Indeed, live access to HIS will be an integral feature of HydroHUB. But the advantages will be a two-way street. The vision for HIS has always been that the data access would support improved modeling and prediction in hydrology. HydroHUB will contribute another step toward making that vision a reality.