High Performance Computing: The Computational Resources behind the Agency’s Environmental Modeling and Visualization
High Performance Computing (HPC) provides the infrastructure, software and technical support for EPA researchers and scientists to run their own compute jobs on EPA HPC machines. This enables quick and easy access to the resources needed for a variety of research, including work on projects such as the Community Multiscale Air Quality Model (CMAQ) -- a powerful computational tool used by EPA and states for air quality management -- the Coastal Generalized Ecosystem Model (CGEM) and the Comprehensive Air Quality Model with extensions (CAMx).
High-End Computing Resources
The main high-end scientific computing resource is the HPC system called Atmos. Atmos consists of Dell PowerEdge servers configured with 120 compute nodes. This configuration is comprised of 15,360 cores, 12 debug nodes, two single processor nodes, two large memory nodes, and 16 GPU-ready nodes that currently function as ordinary compute nodes. HPC also has four other GPU nodes and another 36 compute nodes with a total of 1,728 cores from its previous system.
Compute time on Atmos is shared by EPA scientists and researchers to run models that study -- among other things -- air quality, water quality, contaminant transport, and the effects of chemicals on human and ecosystem health. For example, the Center for Computational Toxicology and Exposure (CCTE) previously used HPC to study the chemical and molecular properties of contaminants while investigating toxicity and the risk to people and the environment. More recently, the Office of Research and Development's Atmospheric & Environmental Systems Modeling Division (AESMD) has partnered with HPC on multiple projects.
Projects are allocated time on the HPC system through an annual review process. In FY 2025, for example, projects were allocated around 51 million CPU hours. Available compute hours have increased since then, because HPC forecasts carefully to meet anticipated demand.
Visualization Resources
Sophisticated visualization hardware and software support high-end, R&D visualization computing, providing the ideal technology for projects such as modeling the human respiratory system or air pollutant dispersion through an urban landscape. These visualizations can be converted to animations for display or graphics suitable for publishing.