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

BER Research Highlights

New Deep Cloud Representation Improves Climate Model Simulations during El Niño
Published: January 12, 2009
Posted: January 27, 2009

Clouds block large amounts of sunlight from reaching the Earth's surface during El Niño.  This shielding effect has largely been missing in the community climate model, CAM3.  Scientists in DOE's Atmospheric Radiation Measurement (ARM) program corrected this long-standing model deficiency by using an improved representation of atmospheric convection based on the ARM observations.  The investigators found that the lack of cloud shielding effect in the climate model was caused by poor simulation of low-level cloud cover and water content in the clouds during El Niño.  The addition of improved convection representation suppressed what had been overly active deep clouds in the model, making shallow clouds more active, and leading to more low-level clouds than found in the standard model configuration.  The improved model also had better representation of water content anomalies in clouds which were higher due to enhanced transport of water vapor by shallow clouds to the lower-middle troposphere.  The improvement of the model's representation of clouds corrected the cloud shielding effect in the community climate model.


Li, G, and GJ Zhang, 2008: Understanding biases in shortwave cloud radiative forcing in the National Center for Atmospheric Research Community Atmosphere Model (CAM3) during El Niño. J. Geophys. Res. 113, D02103, doi:10.1029/2007JD008963.

Contact: Kiran Alapaty, SC-23.1, (301) 903-3175
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)