ESRL Quarterly Newsletter - Winter 2009

Building Connections

New ESRL computing specialists advance federal efforts to link, improve Earth system models

globe puzzle.

A coupled air-ocean-wave model lets scientists at the Naval Research Laboratory better predict the impact of hurricanes on the Gulf Coast. Researchers working with a NASA atmospheric general circulation model can swap in different chemistry packages, depending on the problem they are studying. People downloading data generated for the next Intergovernmental Panel on Climate Change, IPCC, assessment will get consistent, thorough descriptions of the many models and experiments involved.

NESII software infrastructure makes these systems work. The new NOAA Environmental Software Infrastructure and Interoperability group, led by Cecelia DeLuca, moved in November from the National Center for Atmospheric Research to ESRL, bringing along a suite of projects focused on building, coupling, and using Earth system models. The need for interoperability between such models is growing, DeLuca said.

“For example, as computing power increases and global models can be run at higher resolution, climate modelers are interacting with weather modelers to understand and improve representation of smaller-scale processes,” DeLuca said. But often, weather and climate models cannot “speak” to one another because they were built so differently. So DeLuca’s team writes code that allows models from very different origins to interact. And that code is not just for linking components of weather and climate models— NESII helps modelers working in space weather, hydrology, and coastal processes build models that interact well with others.

“We grew up at NCAR, but as our group evolved, we got more and more involved with the federal modeling centers,” DeLuca said, explaining her team’s move to ESRL. “NOAA offers closer proximity to the modeling groups we are working with, and NOAA has a service philosophy that’s closer to our values and the goals of our work.”

One of NESII’s main projects is the Earth System Modeling Framework, ESMF, which the team began working on in 2002 with many community partners. ESMF lets modelers wrap their whole model (or individual components) in standard interfaces. It also offers toolkits for grid remapping, time management, and other common functions. The project’s sponsors include NOAA, the National Science Foundation, the Department of Defense, and the National Aeronautics and Space Administration, NASA. ESMF has been incorporated into models funded by each of these agencies and is managed by a multi-agency consortium.

DeLuca’s group includes 10 people, from software engineers and computational scientists to metadata and database experts. Six work remotely from locations across the country; four work from ESRL: DeLuca, NESII manager; Sylvia Murphy, a technical project manager; Silverio Vasquez, ESMF tester and release manager; and Robert Oehmke, a computer scientist.

Mark Govett, from ESRL’s Global Systems Division, said NESII’s move demonstrates NOAA’s growing recognition that collaboration is critical in Earth system modeling. Increasingly, agencies are using pieces of one another’s code, often informally, he said. That means when ESRL, for example, makes a change to an atmospheric model, it might be critical for the U.S. Environmental Protection Agency to understand how the change could affect their air pollution models.

“As models become increasingly complex, we can no longer afford to develop every part of Earth system models ourselves. We must collaborate with other laboratories and agencies, and use tools such as ESMF to link the science needed,” Govett said. “ NESII is helping us do that in a formal way.”

Some of NESII’s current projects

Global Interoperability Program (GIP): The new GIP program includes projects involving weather prediction, climate research, and teaching graduate students how to build and use models. What connects these efforts is a base of software infrastructure – some shared, and some specialized – built by NESII and other groups around the country and the world. GIP, which is funded by the NOAA Climate Program Office, is working to improve the software that underlies high-priority efforts such as the fifth IPCC assessment, due in 2014. The goal is to help ensure that the United States can respond to increasing demands for weather and climate information.

Earth System Curator: The Curator project builds software to support running, documenting, and using climate models. The current focus is on delivering a system for displaying the model metadata collected for the fifth IPCC assessment. It’s a broad effort: Curator is supported by the NSF and NASA, and works closely with the DOE’s Earth System Grid data portal, and other partners from federal, academic, and international institutions. The metadata available for the upcoming assessment will be a big improvement over what was available for the IPCC’s fourth assessment report, DeLuca said. “When you’re downloading the older data, it’s hard to tell, ‘What’s the difference between these two model versions? Did that run include the indirect effects of aerosols? ’”

Earth System Modeling Framework (ESMF): ESMF continues to grow and evolve, taking on new grids, new remapping approaches, new computing platforms, new communities who are interested in it, and different ways of linking components. Much of the NESII group’s time is spent on ongoing development and support of the framework, as more and more modelers around the world seek to use it.

National Unified Operational Prediction Capability (NUOPC): The Air Force, Navy, and NOAA are coordinating to improve their operational forecasting systems, and collaborating on a new multi-model ensemble for numerical weather prediction that’s based on ESMF. A central element of the ensemble is the National Environmental Modeling System (NEMS), a next-generation weather model being developed by the National Weather Service. NEMS uses ESMF to connect to other models and model components for research and operations, including ESRL’s Flow-following finite-volume Icosahedral Model. NESII staff has been working with NUOPC partners to understand operational requirements and lay out a plan for technical development.

NESII is also involved the Battlespace Environments Institute, an effort within the Department of Defense to create an ESMF-based “whole Earth modeling environment,” and the Modeling Analysis and Prediction Program at NASA, which used ESMF extensively to develop the GEOS-5 atmospheric general circulation model.