TY - JOUR KW - Arctic clouds KW - Cloud-resolving models KW - Mixed-phase cloud KW - Single-column models AU - Stephen A Klein AU - Renata B McCoy AU - Hugh Morrison AU - Andrew S Ackerman AU - Alexander Avramov AU - Gijs de Boer AU - Mingxuan Chen AU - Jason N. S Cole AU - Anthony Del Genio AU - Michael Falk AU - Michael J Foster AU - Ann M Fridlind AU - Jean-Christophe Golaz AU - Tempei Hashino AU - Jerry Y Harrington AU - Corinna Hoose AU - Marat F Khairoutdinov AU - Vincent E Larson AU - Xiaohong Liu AU - Yali Luo AU - Greg M McFarquhar AU - Surabi Menon AU - Roel A. J Neggers AU - Sungsu Park AU - Michael R Poellot AU - Jerome M Schmidt AU - Igor Sednev AU - Ben J Shipway AU - Matthew D Shupe AU - Douglas A Spangenberg AU - Yogesh C Sud AU - David D Turner AU - Dana E Veron AU - Knut von Salzen AU - Gregory K Walker AU - Zhien Wang AU - Audrey B Wolf AU - Shaocheng Xie AU - Kuan-Man Xu AU - Fanglin Yang AU - Gong Zhang AB -

Results are presented from an intercomparison of single-column and cloud-resolving model simulations of a cold-air outbreak mixed-phase stratocumulus cloud observed during the Atmospheric Radiation Measurement (ARM) programme's Mixed-Phase Arctic Cloud Experiment. The observed cloud occurred in a well-mixed boundary layer with a cloud-top temperature of − 15 °C. The average liquid water path of around 160 g m−2was about two-thirds of the adiabatic value and far greater than the average mass of ice which when integrated from the surface to cloud top was around 15 g m−2. Simulations of 17 single-column models (SCMs) and 9 cloud-resolving models (CRMs) are compared. While the simulated ice water path is generally consistent with observed values, the median SCM and CRM liquid water path is a factor-of-three smaller than observed. Results from a sensitivity study in which models removed ice microphysics suggest that in many models the interaction between liquid and ice-phase microphysics is responsible for the large model underestimate of liquid water path. Despite this underestimate, the simulated liquid and ice water paths of several models are consistent with observed values. Furthermore, models with more sophisticated microphysics simulate liquid and ice water paths that are in better agreement with the observed values, although considerable scatter exists. Although no single factor guarantees a good simulation, these results emphasize the need for improvement in the model representation of mixed-phase microphysics.

BT - Quarterly Journal of the Royal Meteorological Society DA - 04/2009 DO - 10.1002/qj.416 IS - 641 Part B N2 -

Results are presented from an intercomparison of single-column and cloud-resolving model simulations of a cold-air outbreak mixed-phase stratocumulus cloud observed during the Atmospheric Radiation Measurement (ARM) programme's Mixed-Phase Arctic Cloud Experiment. The observed cloud occurred in a well-mixed boundary layer with a cloud-top temperature of − 15 °C. The average liquid water path of around 160 g m−2was about two-thirds of the adiabatic value and far greater than the average mass of ice which when integrated from the surface to cloud top was around 15 g m−2. Simulations of 17 single-column models (SCMs) and 9 cloud-resolving models (CRMs) are compared. While the simulated ice water path is generally consistent with observed values, the median SCM and CRM liquid water path is a factor-of-three smaller than observed. Results from a sensitivity study in which models removed ice microphysics suggest that in many models the interaction between liquid and ice-phase microphysics is responsible for the large model underestimate of liquid water path. Despite this underestimate, the simulated liquid and ice water paths of several models are consistent with observed values. Furthermore, models with more sophisticated microphysics simulate liquid and ice water paths that are in better agreement with the observed values, although considerable scatter exists. Although no single factor guarantees a good simulation, these results emphasize the need for improvement in the model representation of mixed-phase microphysics.

PY - 2009 SP - 979 EP - 1002 T2 - Quarterly Journal of the Royal Meteorological Society TI - Intercomparison of model simulations of mixed-phase clouds observed during the ARM Mixed-phase Arctic cloud experiment. Part I: Single layer cloud VL - 135 ER -