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

Aug 24, 2019
New Approach for Studying How Microbes Influence Their Environment
A diverse group of scientists suggests a common framework and targeting of known microbial processes [more...]

Aug 08, 2019
Nutrient-Hungry Peatland Microbes Reduce Carbon Loss Under Warmer Conditions
Enzyme production in peatlands reduces carbon lost to respiration under future high temperatures. [more...]

Aug 05, 2019
Amazon Forest Response to CO2 Fertilization Dependent on Plant Phosphorus Acquisition
AmazonFACE Model Intercomparison. The Science Plant growth is dependent on the availabi [more...]

Jul 29, 2019
A Slippery Slope: Soil Carbon Destabilization
Carbon gain or loss depends on the balance between competing biological, chemical, and physical reac [more...]

Jul 15, 2019
Field Evaluation of Gas Analyzers for Measuring Ecosystem Fluxes
How gas analyzer type and correction method impact measured fluxes. The Science A side- [more...]

List all highlights (possible long download time)