
Over 17 months, Andrew Jaruga engineered advanced atmospheric modeling features for the CliMA/CloudMicrophysics.jl repository, focusing on microphysics, thermodynamics, and diagnostics. He developed GPU-accelerated sedimentation and tracer statistics, refactored microphysics interfaces for maintainability, and enhanced numerical stability in precipitation and diffusion schemes. Using Julia and Fortran interfaces, Andrew integrated new parameterizations, improved configuration management, and automated CI/CD pipelines for robust testing and release workflows. His work addressed mass balance, performance, and physical realism, enabling scalable, accurate climate simulations. The depth of his contributions is reflected in the breadth of features delivered and the reliability of the resulting software.

February 2026 (CliMA/ClimaAtmos.jl): Delivered GPU-accelerated advanced diagnostics statistics for tracer fields, enabling per-vertical-level analysis with max, mean, and sum metrics for both negative and positive values. Implemented 1D negative tracers statistics in the output and extended GPU paths to support negative statistics, enhancing observability and analysis capabilities across the vertical grid.
February 2026 (CliMA/ClimaAtmos.jl): Delivered GPU-accelerated advanced diagnostics statistics for tracer fields, enabling per-vertical-level analysis with max, mean, and sum metrics for both negative and positive values. Implemented 1D negative tracers statistics in the output and extended GPU paths to support negative statistics, enhancing observability and analysis capabilities across the vertical grid.
January 2026 monthly summary for CliMA/CloudMicrophysics.jl: Delivered Thermodynamics Interface Upgrade and completed a release cycle with v0.31.0 release and documentation fixes. Key outcomes include improved thermodynamics accuracy and performance, a clean minor release, and strengthened onboarding and release-readiness for downstream users. This work enhances model fidelity, stability, and developer experience.
January 2026 monthly summary for CliMA/CloudMicrophysics.jl: Delivered Thermodynamics Interface Upgrade and completed a release cycle with v0.31.0 release and documentation fixes. Key outcomes include improved thermodynamics accuracy and performance, a clean minor release, and strengthened onboarding and release-readiness for downstream users. This work enhances model fidelity, stability, and developer experience.
December 2025 monthly summary: Delivered cross-repo enhancements to improve atmospheric diffusion fidelity, soil gas accuracy, diagnostics, and visualization reliability. Implemented a configurable constant horizontal diffusion option, synchronized soil gas parameters to release 1.2.0 where applicable, expanded soil prognostics, and strengthened the diagnostic framework with covariance analysis and plotting fixes to support more actionable insights for model development and decision-making.
December 2025 monthly summary: Delivered cross-repo enhancements to improve atmospheric diffusion fidelity, soil gas accuracy, diagnostics, and visualization reliability. Implemented a configurable constant horizontal diffusion option, synchronized soil gas parameters to release 1.2.0 where applicable, expanded soil prognostics, and strengthened the diagnostic framework with covariance analysis and plotting fixes to support more actionable insights for model development and decision-making.
November 2025 — CliMA/ClimaAtmos.jl: Delivered thermodynamics and moisture stability enhancements along with a latent heat bug fix in bg_gradient, significantly improving moisture transport accuracy and buoyancy-related calculations. These changes advance model realism, stability, and scientific value for weather and climate predictions.
November 2025 — CliMA/ClimaAtmos.jl: Delivered thermodynamics and moisture stability enhancements along with a latent heat bug fix in bg_gradient, significantly improving moisture transport accuracy and buoyancy-related calculations. These changes advance model realism, stability, and scientific value for weather and climate predictions.
October 2025: In two repos, achieved improved stability, scalability, and usability for CliMA simulations. Key features delivered include 1M flame scheme support with adjusted flame graph allocation and reference counting, and documentation updates including a new limiter behavior plot. Major bugs fixed address numerical stability and mass balance: double-sided limiting for triangle_inequality_limiter to prevent negative source terms, and improved epsilon handling in CloudMicrophysics to avoid division-by-zero. Overall impact includes more robust, scalable simulations and readiness for release, with improved visibility into limiter behavior for end users. Technologies demonstrated include Julia performance optimization, memory management (reference counting and flame graphs), numerical stability techniques, dependency management, and thorough documentation.
October 2025: In two repos, achieved improved stability, scalability, and usability for CliMA simulations. Key features delivered include 1M flame scheme support with adjusted flame graph allocation and reference counting, and documentation updates including a new limiter behavior plot. Major bugs fixed address numerical stability and mass balance: double-sided limiting for triangle_inequality_limiter to prevent negative source terms, and improved epsilon handling in CloudMicrophysics to avoid division-by-zero. Overall impact includes more robust, scalable simulations and readiness for release, with improved visibility into limiter behavior for end users. Technologies demonstrated include Julia performance optimization, memory management (reference counting and flame graphs), numerical stability techniques, dependency management, and thorough documentation.
September 2025 monthly performance summary highlighting business value and technical achievements across CliMA/CloudMicrophysics.jl and CliMA/ClimaAtmos.jl. Focused on parameter loading robustness, automation reliability, host-model coupling clarity, and streamlined release management to enable safer deployments and more accurate simulations.
September 2025 monthly performance summary highlighting business value and technical achievements across CliMA/CloudMicrophysics.jl and CliMA/ClimaAtmos.jl. Focused on parameter loading robustness, automation reliability, host-model coupling clarity, and streamlined release management to enable safer deployments and more accurate simulations.
August 2025: Delivered key features and stability improvements across CliMA CloudMicrophysics.jl, ClimaAtmos.jl, and Thermodynamics.jl. Highlights include naming standardization for cloud phase (lcl/icl), refinement to prevent spurious ice formation in warm conditions, and diffusion improvements for microphysics tracers; plus sedimentation velocity refactor to fix EDMF/EDMFx SGS mass flux. Also implemented a temporary coupler test adjustment and CI build trigger, and completed dependency upgrades for core libraries. These work items collectively enhance physical realism, numerical stability, and cross-repo compatibility, enabling more reliable forecasts and smoother upstream integration.
August 2025: Delivered key features and stability improvements across CliMA CloudMicrophysics.jl, ClimaAtmos.jl, and Thermodynamics.jl. Highlights include naming standardization for cloud phase (lcl/icl), refinement to prevent spurious ice formation in warm conditions, and diffusion improvements for microphysics tracers; plus sedimentation velocity refactor to fix EDMF/EDMFx SGS mass flux. Also implemented a temporary coupler test adjustment and CI build trigger, and completed dependency upgrades for core libraries. These work items collectively enhance physical realism, numerical stability, and cross-repo compatibility, enabling more reliable forecasts and smoother upstream integration.
July 2025 monthly summary: The CliMA development stack delivered significant physics upgrades, stability improvements, and release-ready enhancements with clear business value. Core physics enhancements were implemented across CliMAAtmos.jl and CloudMicrophysics.jl, complemented by API refinements and CI optimizations that accelerated feedback and reduced turnaround time for fixes and experiments. Release engineering across the suite was completed to prepare for production use and external distribution.
July 2025 monthly summary: The CliMA development stack delivered significant physics upgrades, stability improvements, and release-ready enhancements with clear business value. Core physics enhancements were implemented across CliMAAtmos.jl and CloudMicrophysics.jl, complemented by API refinements and CI optimizations that accelerated feedback and reduced turnaround time for fixes and experiments. Release engineering across the suite was completed to prepare for production use and external distribution.
June 2025 monthly summary for CliMA development: Delivered release-ready improvements, reliability enhancements, and significant refactors across CloudMicrophysics.jl and ClimaAtmos.jl. Implemented release and dependency consolidation with patch-level version bumps, Thermodynamics.toml fixes, and parameter rename handling; upgraded CI tooling to support Julia v1.11 and Codecov reporting; refactored thermodynamics and microphysics interfaces for maintainability and extensibility; enhanced Rain and 2M microphysics schemes to include rain/snow in thermodynamics calculations with adjusted signatures; fixed a non-equilibrium segmentation fault in Parcels under Julia v1.11 via condensation/deposition refactor and updated documentation. Also included dependency upgrades in ClimaAtmos.jl (CloudMicrophysics v0.23 and ClimaParams).
June 2025 monthly summary for CliMA development: Delivered release-ready improvements, reliability enhancements, and significant refactors across CloudMicrophysics.jl and ClimaAtmos.jl. Implemented release and dependency consolidation with patch-level version bumps, Thermodynamics.toml fixes, and parameter rename handling; upgraded CI tooling to support Julia v1.11 and Codecov reporting; refactored thermodynamics and microphysics interfaces for maintainability and extensibility; enhanced Rain and 2M microphysics schemes to include rain/snow in thermodynamics calculations with adjusted signatures; fixed a non-equilibrium segmentation fault in Parcels under Julia v1.11 via condensation/deposition refactor and updated documentation. Also included dependency upgrades in ClimaAtmos.jl (CloudMicrophysics v0.23 and ClimaParams).
May 2025 performance summary for the CliMA software stack. Delivered stability-focused improvements across CloudMicrophysics.jl, ClimaAtmos.jl, ClimaCoupler.jl, and ClimaParams.jl, emphasizing numerical robustness, interface enhancements, and release readiness. The month emphasizes business value through more reliable physics kernels, expanded configurability, and up-to-date dependencies, enabling more accurate forecasts and smoother deployment in production workflows.
May 2025 performance summary for the CliMA software stack. Delivered stability-focused improvements across CloudMicrophysics.jl, ClimaAtmos.jl, ClimaCoupler.jl, and ClimaParams.jl, emphasizing numerical robustness, interface enhancements, and release readiness. The month emphasizes business value through more reliable physics kernels, expanded configurability, and up-to-date dependencies, enabling more accurate forecasts and smoother deployment in production workflows.
April 2025 performance-focused monthly summary: Across the CliMA suite, delivered targeted microphysics improvements, ML-augmented parameterizations, and test/CI stability enhancements. Key outcomes include: improved numerical stability and accuracy in CloudMicrophysics.jl; ML CDNC and CDND parameter enhancements with dependency updates; updated ClimaParams.jl and related manifests; test isolation improvements and handling of non-deterministic tests; and refined humidity calculations in Thermodynamics.jl. These changes collectively increase model robustness, reproducibility, and business value by enabling more reliable climate predictions, smoother deployment, and clearer pathways for ML integration.
April 2025 performance-focused monthly summary: Across the CliMA suite, delivered targeted microphysics improvements, ML-augmented parameterizations, and test/CI stability enhancements. Key outcomes include: improved numerical stability and accuracy in CloudMicrophysics.jl; ML CDNC and CDND parameter enhancements with dependency updates; updated ClimaParams.jl and related manifests; test isolation improvements and handling of non-deterministic tests; and refined humidity calculations in Thermodynamics.jl. These changes collectively increase model robustness, reproducibility, and business value by enabling more reliable climate predictions, smoother deployment, and clearer pathways for ML integration.
In March 2025, the CliMA team delivered notable CI, parameterization, and microphysics enhancements across four core repositories. Key outcomes include CI performance improvements, data-driven parameterization for cloud droplet concentrations, richer precipitation microphysics and caching architecture, and cross-repo compatibility updates with upstream dependencies. These changes enhance model fidelity, CI reliability, and long-term maintainability, enabling faster iteration and more accurate simulations while reducing maintenance toil.
In March 2025, the CliMA team delivered notable CI, parameterization, and microphysics enhancements across four core repositories. Key outcomes include CI performance improvements, data-driven parameterization for cloud droplet concentrations, richer precipitation microphysics and caching architecture, and cross-repo compatibility updates with upstream dependencies. These changes enhance model fidelity, CI reliability, and long-term maintainability, enabling faster iteration and more accurate simulations while reducing maintenance toil.
February 2025 monthly summary: Delivered substantial cloud microphysics improvements, transport/advective refinements, and diagnostics enhancements across CliMA repositories. The work improves physical realism, numerical stability, and observability, enabling more reliable climate simulations and easier validation workflows. Key outcomes include dynamic effective radius handling, safer precipitation flux computations, expanded multi-tracer transport, and updated validation/diagnostics tooling across ClimaAtmos.jl, ClimaParams.jl, RRTMGP.jl, and CloudMicrophysics.jl.
February 2025 monthly summary: Delivered substantial cloud microphysics improvements, transport/advective refinements, and diagnostics enhancements across CliMA repositories. The work improves physical realism, numerical stability, and observability, enabling more reliable climate simulations and easier validation workflows. Key outcomes include dynamic effective radius handling, safer precipitation flux computations, expanded multi-tracer transport, and updated validation/diagnostics tooling across ClimaAtmos.jl, ClimaParams.jl, RRTMGP.jl, and CloudMicrophysics.jl.
January 2025 monthly performance summary for CliMA projects. Delivered GPU-accelerated sedimentation velocity improvements in CloudMicrophysics.jl, advanced non-equilibrium microphysics handling in ClimaAtmos.jl, and strengthened CI/test infrastructure for fluids and precipitation model integrations. These changes improved simulation performance, numerical stability, and modeling accuracy, enabling faster, more reliable, and scalable atmospheric simulations. Business value includes faster GPU-backed computations, more accurate implicit solvers for microphysics, and robust testing pipelines to support ongoing development and release readiness.
January 2025 monthly performance summary for CliMA projects. Delivered GPU-accelerated sedimentation velocity improvements in CloudMicrophysics.jl, advanced non-equilibrium microphysics handling in ClimaAtmos.jl, and strengthened CI/test infrastructure for fluids and precipitation model integrations. These changes improved simulation performance, numerical stability, and modeling accuracy, enabling faster, more reliable, and scalable atmospheric simulations. Business value includes faster GPU-backed computations, more accurate implicit solvers for microphysics, and robust testing pipelines to support ongoing development and release readiness.
December 2024 performance overview focusing on delivering realism, maintainability, and validation capabilities across CliMAAtmos.jl, ClimaParams.jl, and CloudMicrophysics.jl. Key features include a new exponential height-decay vertical diffusion model, a refactored cloud modeling architecture with improved quadrature handling and documentation, and a GPU-enabled testing/CI workflow to strengthen validation across GPU-enabled workloads. These changes enhance forecast realism, reduce technical debt, and improve the reliability of the testing pipeline for accelerated iteration.
December 2024 performance overview focusing on delivering realism, maintainability, and validation capabilities across CliMAAtmos.jl, ClimaParams.jl, and CloudMicrophysics.jl. Key features include a new exponential height-decay vertical diffusion model, a refactored cloud modeling architecture with improved quadrature handling and documentation, and a GPU-enabled testing/CI workflow to strengthen validation across GPU-enabled workloads. These changes enhance forecast realism, reduce technical debt, and improve the reliability of the testing pipeline for accelerated iteration.
November 2024 performance highlights for CliMA software: delivered physics modeling improvements, expanded test coverage, documentation stability, CI/release improvements, and new long-run capabilities for non-equilibrium moist physics.
November 2024 performance highlights for CliMA software: delivered physics modeling improvements, expanded test coverage, documentation stability, CI/release improvements, and new long-run capabilities for non-equilibrium moist physics.
October 2024 performance summary for CliMA/CloudMicrophysics.jl: Delivered shape-based snow particle dynamics enhancements enabling terminal velocities based on particle shape (oblate or prolate) with aspect ratio calculations and refactored the Chen2022 parameterization to support variable apparent ice and snow densities. Introduced distinct types for small and large ice particles; updated documentation and internal API calls to reflect the new parameters. This work increases physical realism of snow microphysics, enabling more accurate climate simulations and flexible experimentation with density assumptions. No major bugs fixed this month.
October 2024 performance summary for CliMA/CloudMicrophysics.jl: Delivered shape-based snow particle dynamics enhancements enabling terminal velocities based on particle shape (oblate or prolate) with aspect ratio calculations and refactored the Chen2022 parameterization to support variable apparent ice and snow densities. Introduced distinct types for small and large ice particles; updated documentation and internal API calls to reflect the new parameters. This work increases physical realism of snow microphysics, enabling more accurate climate simulations and flexible experimentation with density assumptions. No major bugs fixed this month.
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