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Environmental Modeling Community of Practice

Hydrologic Micro Services HMS


Historically, legacy models have worked independently to solve specific questions. Most models do not have efficient automated input data provisioning services, resulting in modelers spending more time on input data gathering and pre-processing rather than analyzing model outputs. Environmental modeling is moving forward to meet the needs of multimedia platforms and interoperability between new data and models. To understand why results differ between one model to another, transparency of the methodology and reproducibility of data are needed. We developed a hydro-informatics platform called Hydrologic Micro Services (HMS) to address the importance of interoperability, transparency,  reproducibility, and efficiency in environmental modeling (Parmar et al., 2018).

HMS was created to break the barriers of old models and datasets constrained by legacy formats and connect them to newer formats, advanced models, and workflows. The motivation behind HMS was to support and address problems of the hydrology and water quality modeling community. We developed this tool for users including private, public and academic sectors on the local, state, and federal level. The HMS platform is a collection of hydrologic and water quality data provisioning web services and modeling components. HMS data provisioning web services purvey raw data through online script requests for hydrologic parameters including precipitation, air temperature, solar radiation, soil moisture, evapotranspiration, surface and subsurface flow, and runoff. A component is a distinct software module that the user can incorporate and link into existing models. For example, components that have been incorporated and compiled into HMS include normalized difference vegetation index, sediment diagenesis, eutrophication, and kinetic transformation of nutrients and chemicals. HMS enables users to rapidly characterize the hydrology of a watershed, reduce their time on data gathering and preprocessing, and to easily parameterize model workflows. One service of the HMS platform is the Precipitation Comparison and Analysis Tool (HMS-PCAT), which is the focus of this paper. HMS-PCAT provides an intuitive online interface for precipitation data source exploration and data download, irrespective of computing platforms or coding languages (Parmar et al., 2018).


Parmar, R., Knightes, C. D., Smith, D., Wolfe, K., Koblich, J., Sitterson, J., Johnston, J.M, and Purucker, T. (2018). Hydrological Micro Services. Paper presented at the Proceedings of the 9th International Congress on Environmental Modelling and Software, Fort Collins, CO.


HMS platform is under development and is available only for evaluation and review purposes.

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