Provide a computing environment tailored to user needs

CISL’s success in supporting scientific goals and enabling scientific impact depends in equal measure on understanding the needs and research objectives of its several user communities and on integrating CISL’s resources, capabilities, and services in response to those needs. In FY2017, these user communities included more than 1,700 users at more than 330 universities and other institutions who benefited from using CISL’s high-performance cyberinfrastructure (CI) and services. More than 530 new users joined the CISL computing community in FY2017.

Supercomputer usage
The FY2017 usage of Cheyenne and Yellowstone by CISL’s major user communities shows the more rapid migration of NCAR users to Cheyenne compared to the university community, with strong continued Yellowstone use by university and Wyoming users. The Cheyenne ASD projects include both university and NCAR activities.


A discipline-specific approach to supercomputing allows CISL to tailor system design and services for our user communities while satisfying the highly specialized technical requirements of scientific applications such as climate system models. Most significantly in FY2017, CISL released the new 5.34-petaflops Cheyenne high-performance computer system for production work on January 12, 2017.

Also in FY2017, CISL continued its migration of CMIP5 data to the CMIP Analysis Platform, which was introduced in FY2016 as an allocated and supported service for users interested in climate model intercomparisons. The platform allows users to conduct large-scale analyses on a “lending library” of published CMIP5 data; more than 20 TB of non-NCAR CMIP5 data were being hosted by CISL at the end of FY2017.

With respect to supercomputing services, more than 70% of CISL’s HPC system use is related to running NCAR-developed climate and weather applications. This well-defined workload allows CISL and NCAR scientists to optimize the most heavily used models and applications on current and future systems. It also ensures that model development and research in Earth System processes can occur in a controlled yet responsive environment where researchers can prepare complex models and perform the computationally demanding tests required to validate them.

The size, breadth, and disciplinary pursuits of CISL’s user communities offer perspectives on the scientific impact enabled by CISL’s HPC, data analysis, and archival resources. These user communities reported nearly 600 publications and more than 100 dissertations and theses resulting from CISL HPC support in FY2016 (the timeframe of our most recent survey). Scientifically, our user communities span 17 areas of interest in the atmospheric and related sciences.

CISL works to provide equitable and efficient access to several distinct communities of researchers in the atmospheric and related sciences, including the university community, Climate Simulation Laboratory users, NCAR researchers, and University of Wyoming researchers through the Wyoming-NCAR Alliance. In FY2017, CISL continued to manage several allocation processes to distribute resources and ensure access by the most meritorious projects.

Approximately 28% of the new Cheyenne system and 29% of Yellowstone was available to U.S.-based university researchers with NSF awards in the atmospheric or related sciences. University requests are reviewed twice per year by the CISL HPC Allocation Panel (CHAP). In October 2016 and April 2017 combined, the CHAP reviewed 88 requests for 459 million core-hours on the Cheyenne and Yellowstone systems. In addition, university researchers, graduate students, and postdoctoral researchers submitted 279 small allocation requests.

University allocations
CISL allocations to university researchers have supported the scientific objectives of more than 150 different NSF awards each year for the past decade. In FY2017, active projects supported 336 unique NSF awards.


In geographic scope, CISL’s university users represent hundreds of different universities and collaborating institutions, primarily in the U.S. as defined by our HPC mission. In FY2017, active projects supported more than 330 unique NSF awards, and 919 university projects were open during the year on CISL resources (an 11% increase over FY2016).

Comparable portions of Cheyenne (28%) and Yellowstone (29%) were also allocated in FY2017 to NCAR researchers to support the computational needs of the NCAR laboratories, including NCAR Strategic Capability (NSC) projects. Requests for large-scale Cheyenne projects were reviewed in October 2016 and April 2017 by a panel of NCAR computational scientists and approved by the NCAR Executive Committee.

About 27% of Cheyenne and 28% of Yellowstone was made available to the Climate Simulation Lab (CSL) at NCAR in FY2017 after review by the CHAP. In addition to supporting the CESM community allocation, CSL projects engage researchers funded by NSF awards to pursue climate-related science questions requiring large-scale simulations of Earth’s climate system.

The Wyoming-NCAR Alliance (WNA), which targets geosciences collaborations among the University of Wyoming, NCAR, and institutions in other EPSCoR states, convened the Wyoming Resource Allocation Panel (WRAP) in January and June 2017. In FY2017, the WNA awarded 130 million core-hours to 11 large projects, and supported 10 small allocations; 29 different WNA projects used more than 105 million Yellowstone and Cheyenne core-hours.

This work is a crucial part of CISL’s computing imperative to provide hardware cyberinfrastructure customized for the atmospheric and related sciences. This ongoing service for users is supported by NSF Core funds including CSL funding. Funding from the University of Wyoming supports the Wyoming Resource Allocation Panel (WRAP).