Background

The Goddard Earth Observing System (GEOS) model consists of a number of different model components//configurations//elements and tools that can address various Earth systems and science questions. The GEOS model follows the Earth System Modelling Framework (ESMF) architecture which informs the coupling of Earth System Modelling components in GEOS. The ASTG has provided scientific software support and development to the Chemistry-Climate Model (CCM), and the Chemistry-Transport Model (CTM) GEOS configurations, including the development of new features, programming tasks, visualization and analysis support.

Chemistry Climate Model

The CCM configuration of GEOS includes a chemistry component that includes feedbacks between the chemical composition and ciruclation of the atmosphere.

Chemistry-Transport Model

The CTM incorporates a predictive framework to calculate chemical reactions, including specified meteorological conditions like temperature, winds, etc., that are pre-calculated. In contrast to the CCM, the CTM enables chemical distributions to be impacted by chemical processes without allowing feedbacks on circulation.

Impact

ASTG provides a wealth of knowledge and experience supporting GEOS models, and long term expertise//support of GEOS has eased improvement and addition of model features, tools, and extensions. ASTG has recently upgraded visualization and analysis support of GEOS models with the development of the eViz package, which contains easy-to-use built-in GEOS configurations and specialized plotting.

Background

The Goddard Institude for Space Studies general circulation model, known as modelE, provides the ability to simulate many different configurations of Earth System Models — including interactive atmospheric chemistry, aerosols, carbon cycle and other tracers, as well as the standard atmosphere, ocean, sea ice and land surface components.

Impact

ASTG has worked with GISS scientists over more than 10 years helping to improve some aspects of the model infrastructure including the incorporation of a regression testing system as well as assisting with the migration of the source code to a Git-based repository. Recent development include new land-surface drivers for GISS’ Ent Terrestrial Biosphere Model and conditional testing options for the Regression Testing System.

Land Information System modes of operation schematic [1].

Background

The ASTG works with the Hydrological Sciences Laboratory to provide software infrastructure support for the NASA Land Information System (LIS) .

“LIS is a flexible land surface modeling and data assimilation framework designed using advanced software engineering principles. Structured to enable community sharing and the reuse of modeling tools, data resources, and assimilation algorithms, the LIS infrastructure provides modeling tools to integrate satellite- and ground-based observational data products and advanced land surface modeling techniques to produce optimal fields of land surface states and fluxes.”

Flexible Regridding Using ESMF

Earth System models, in general, require the use of different numerical gridding specifications. To allow more flexible and achieve performant regridding, the ASTG has recently integrated the Earth System Model Framework (ESMF) regridding tool in LIS.

Parallel I/O using GEOS-ESM/MAPL

Large-scale land surface simulations require the use of large computer clusters. To meet the future requirements and ever increasing resolution demands, LIS has requested the implementation of an efficient parallel I/O framework. Currently, ASTG is addressing this by exploring the use of the GEOS-ESMF/MAPL/pfio, a Parallel Fortran I/O (PFIO) frameowrk.

Background

The NASA-Unified Weather Research and Forecasting (NU-WRF) model is an integrated, observation-driven modeling system representing aerosol, cloud, precipitation, and land processes at satellite-resolved scales. NU-WRF is intended as a superset of the Weather Research and Forecasting model (WRF) and incorporates the GSFC Land Information System (LIS) as well as a WRF-Chem enabled version of the Goddard Chemistry Aerosols Radiation Transport model (GOCART), GSFC radiation and microphysics schemes (with revised couplings to the aerosols), and several pre-processors and utilities to enable the coupling of the aforementioned components. Taken together, the NU- WRF modeling system provides a framework for simulating aerosol and land use effects on such phenomena as floods, tropical cyclones, mesoscale convective systems, droughts, and monsoons.

Impact

ASTG provides support in all aspects of NU-WRF software development. ASTG has been central in the development of the NU-WRF software infrastructure as well as collaborating with scientists to contribute multiple model enhancements. Highlights include: a python-based build system to facilitate compilation of framework components; a regression testing framework for creating workflows that maximize code coverage; several fortran pre-processors to produce WRF model-ready data; multiple WRF/WPS/LIS enhancements to facilitate coupling of state variables among model components.

Software

Current source development is managed in a Gitlab repository. To access the repository contact Carlos Cruz (carlos.a.cruz@nasa.gov) to get an invite [1].

[1] The release of NU-WRF software is subject to NASA legal review, and requires users to sign a Software Usage Agreement.