U.S. Department of Energy Office of Biological and Environmental Research

BER Research Highlights


Community Atmosphere Model with a Cloud “Superparameterization.”
Published: June 18, 2013
Posted: October 23, 2013

Clouds exist in a vast range of conditions and sizes and are, therefore, notoriously difficult to represent in global climate models. Explicitly simulating the physics of individual clouds in climate models would be prohibitively expensive computationally. Instead, clouds in global models are typically represented using parameterizations, or equations that approximate their subgrid-box effects on the larger climate system. For short simulations or small regional domains, the physics of individual clouds has been included, using an embedded cloud resolving model (CRM). Recently, an intermediate approach, called cloud “superparameterization,” has been developed. A team, including U.S. Department of Energy scientists at Pacific Northwest National Laboratory, introduced a cloud superparameterization to the Community Atmosphere Model (CAM). The team’s superparameterization is a two-dimensional version of a CRM that captures the cloud updrafts and downdrafts based on principles of conservation of momentum and energy. Embedded into a global model, the scheme is called a multiscale modeling framework. The particular multiscale modeling framework based on the CAM is called the superparameterized-CAM. Over the past several years, scientists from many institutions have explored the ability of superparameterized-CAM to simulate tropical weather systems, day-night changes of precipitation, Asian and African monsoons, and other climate phenomena. The new model has a stronger physical basis and simulates clouds and cloud-aerosol interactions that are more realistic than simulations with traditional cloud parameterizations, a capability that should improve the ability of climate models to predict climate change.

Reference: Randall, D. A., M. Branson, M. Wang, S. Ghan, C. Craig, A. Gettelman, and D. Edwards. 2013. “A Community Atmosphere Model with Clouds Superparameterized,” Eos, Transactions American Geophysical Union 94(25), 221–22. DOI: 10.1002/2013EO250001. (Reference link)

Contact: Dorothy Koch, SC-23.1, (301) 903-0105
Topic Areas:

  • Research Area: Earth and Environmental Systems Modeling
  • Research Area: Atmospheric System Research

Division: SC-23.1 Climate and Environmental Sciences Division, BER

 

BER supports basic research and scientific user facilities to advance DOE missions in energy and environment. More about BER

Recent Highlights

May 10, 2019
Quantifying Decision Uncertainty in Water Management via a Coupled Agent-Based Model
Considering risk perception can improve the representation of human decision-making processes in age [more...]

May 09, 2019
Projecting Global Urban Area Growth Through 2100 Based on Historical Time Series Data and Future Scenarios
Study provides country-specific urban area growth models and the first dataset on country-level urba [more...]

May 05, 2019
Calibrating Building Energy Demand Models to Refine Long-Term Energy Planning
A new, flexible calibration approach improved model accuracy in capturing year-to-year changes in bu [more...]

May 03, 2019
Calibration and Uncertainty Analysis of Demeter for Better Downscaling of Global Land Use and Land Cover Projections
Researchers improved the Demeter model’s performance by calibrating key parameters and establi [more...]

Apr 22, 2019
Representation of U.S. Warm Temperature Extremes in Global Climate Model Ensembles
Representation of warm temperature events varies considerably among global climate models, which has [more...]

List all highlights (possible long download time)