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

BER Research Highlights


Small Ice Crystals in High-altitude Clouds Do Impact Global Circulations
Published: May 04, 2009
Posted: May 11, 2009

Scientists in DOE's Atmospheric Radiation Measurement (ARM) Program used a global climate model and found that moderate changes in the concentration of small ice crystals in high-altitude clouds, known as Cirrus clouds, had a large impact on the predicted climate.  Using ARM measurements, new mathematical descriptions of ice particle sizes and concentrations, falling speeds, and radiative properties of cirrus clouds were incorporated into a community global climate model.  Moderate increases in small ice crystal concentrations produced lower fall speeds, more cirrus cloud coverage (a 5.5% global increase) and ice content, and warmer atmosphere temperatures (over 3° C) at high altitudes.  In the tropical regions these changes had an overall cooling effect, but a warming effect elsewhere.  Since the present methods to measure concentrations of small ice crystals in cirrus clouds have a high degree of uncertainty, these modeling results underscore the need to improve measurements for better quantification of climate change prediction.

Reference: Mitchell, D.L., P.J. Rasch, D. Ivanova, G.M. McFarquhar, T. Nousiainen (2008), Impact of small ice crystal assumptions on ice sedimentation rates in cirrus clouds and GCM simulations.  Geophys. Res. Lett., 35, L09806, doi:10.1029/2008GL033552 

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)