Climate-Earth system computer model to be the most advanced ever created, says DOE

Armed with high-performance computing systems, DOE national labs and partners tackle climate and Earth-system modeling
September 26, 2014

Computer modeling provides policymakers with essential information on such data as global sea surface temperatures related to specific currents (credit: ACME)

The U.S. Department of Energy national laboratories are teaming up with academia and the private sector to develop what they call the most advanced climate and Earth system computer model yet, and investigate key fundamental science questions, such as the interaction of clouds and climate and the role of secondary organic aerosols.

The project could help address concerns by some that the 55 existing global climate models are inadequate and inconsistent.

Accelerated Climate Modeling for Energy, or ACME, is designed to accelerate the development and application of fully coupled, state-of-the-science Earth system models for scientific and energy applications.

“The national laboratories’ high-performance computing capabilities will enable better regional detail, and the addition of ice sheet processes and improved ocean and sea ice components will help to better quantify future sea-level rise,” said Alan Bishop, principal associate director of Los Alamos National Laboratory’s Science, Technology and Engineering directorate.

Examples of potential stages in a technical roadmap for ACME over seven years (credit: ACME)

The project — which includes seven other national laboratories, four academic institutions, and one private-sector company — will focus initially on three climate-change science drivers and corresponding questions to be answered during the project’s initial phase: water cycle, biogeochemistry, and cryosphere systems.

Over a planned 10-year span, the project aim is to conduct simulations and modeling on the most sophisticated high-performance computing systems as they become available — 100+ petaflop machines and eventually exascale supercomputers.

Water cycle. The project plan hypothesized that: 1) changes in river flow over the last 40 years have been dominated primarily by land management, water management and climate change associated with aerosol forcing; 2) during the next 40 years, greenhouse gas (GHG) emissions in a business as usual scenario may drive changes to river flow.

“A goal of ACME is to simulate the changes in the hydrological cycle, with a specific focus on precipitation and surface water in orographically complex regions such as the western United States and the headwaters of the Amazon,” the report states.

Biogeochemistry. ACME researchers will examine how more complete treatments of nutrient cycles affect carbon-climate system feedbacks, with a focus on tropical systems; and investigate the influence of alternative model structures for below-ground reaction networks on global-scale biogeochemistry–climate feedbacks.

Cryosphere. The team will examine the near-term risks of initiating the dynamic instability and onset of the collapse of the Antarctic Ice Sheet due to rapid melting by warming waters adjacent to the ice sheet grounding lines. The experiment would be the first fully coupled global simulation to include dynamic ice shelf-ocean interactions for addressing the potential instability associated with grounding line dynamics in marine ice sheets around Antarctica.

Initial funding is provided by DOE’s Office of Science.