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Title: Single-Column Model Simulations of Subtropical Marine Boundary-Layer Cloud Transitions Under Weakening Inversions: SCM SIMULATIONS OF CLOUD TRANSITIONS

Abstract

Results are presented of the GASS/EUCLIPSE single-column model inter-comparison study on the subtropical marine low-level cloud transition. A central goal is to establish the performance of state-of-the-art boundary-layer schemes for weather and climate mod- els for this cloud regime, using large-eddy simulations of the same scenes as a reference. A novelty is that the comparison covers four different cases instead of one, in order to broaden the covered parameter space. Three cases are situated in the North-Eastern Pa- cific, while one reflects conditions in the North-Eastern Atlantic. A set of variables is considered that reflects key aspects of the transition process, making use of simple met- rics to establish the model performance. Using this method some longstanding problems in low level cloud representation are identified. Considerable spread exists among models concerning the cloud amount, its vertical structure and the associated impact on radia- tive transfer. The sign and amplitude of these biases differ somewhat per case, depending on how far the transition has progressed. After cloud breakup the ensemble median ex- hibits the well-known “too few too bright” problem. The boundary layer deepening rate and its state of decoupling are both underestimated, while the representation of the thin capping cloudmore » layer appears complicated by a lack of vertical resolution. Encouragingly, some models are successful in representing the full set of variables, in particular the verti- cal structure and diurnal cycle of the cloud layer in transition. An intriguing result is that the median of the model ensemble performs best, inspiring a new approach in subgrid pa- rameterization.« less

Authors:
ORCiD logo [1]; ORCiD logo [2]; ORCiD logo [3]; ORCiD logo [4]; ORCiD logo [5]; ORCiD logo [6]; ORCiD logo [7]; ORCiD logo [8]; ORCiD logo [9]; ORCiD logo [10];  [11]; ORCiD logo [1];  [12]; ORCiD logo [13];  [14]; ORCiD logo [15];  [12]; ORCiD logo [7]; ORCiD logo [15]; ORCiD logo [10] more »; ORCiD logo [8]; ORCiD logo [16]; ORCiD logo [17]; ORCiD logo [18] « less
  1. Institute for Geophysics and Meteorology, Department of Geosciences, University of Cologne, Cologne Germany; Royal Netherlands Meteorological Institute, De Bilt The Netherlands
  2. NASA Goddard Institute for Space Studies, New York NY USA
  3. CIRES, University of Colorado, Boulder CO USA; NOAA Earth System Research Laboratory, Boulder CO USA
  4. Météo France/CNRM, Toulouse France
  5. Météo France/ENM, Toulouse France
  6. Department of Atmospheric Sciences, University of Washington, Seattle WA USA
  7. Met Office, Exeter UK
  8. Royal Netherlands Meteorological Institute, De Bilt The Netherlands
  9. NOAA Center for Weather and Climate Prediction, Environmental Modeling Center, College Park MD USA
  10. Department of Geoscience and Remote Sensing, Delft University of Technology, Delft The Netherlands
  11. Department of Atmospheric Sciences, University of Washington, Seattle WA USA; University of Leeds, Leeds UK
  12. Météo-France/CNRM & CNRS/IPSL/LMD, Toulouse France
  13. Meteorological Research Institute, Climate Research Department, Japan Meteorological Agency, Tsukuba Japan
  14. Department of Atmosphere in the Earth System, Max-Planck Institut für Meteorologie, Hamburg Germany
  15. Department of Mathematical Sciences, University of Wisconsin-Milwaukee, Milwaukee WI USA
  16. Section of Physical Aspects, European Centre for Medium-Range Weather Forecasts, Reading UK
  17. University of California at Los Angeles, Los Angeles CA USA; Pacific Northwest National Laboratory, Richland WA USA
  18. NASA Langley Research Centre, Hampton VI USA
Publication Date:
Research Org.:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1411907
Report Number(s):
PNNL-SA-129345
Journal ID: ISSN 1942-2466; KP1701000
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Advances in Modeling Earth Systems; Journal Volume: 9; Journal Issue: 6
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES

Citation Formats

Neggers, R. A. J., Ackerman, A. S., Angevine, W. M., Bazile, E., Beau, I., Blossey, P. N., Boutle, I. A., de Bruijn, C., Cheng, A., van der Dussen, J., Fletcher, J., Dal Gesso, S., Jam, A., Kawai, H., Cheedela, S. K., Larson, V. E., Lefebvre, M. -P., Lock, A. P., Meyer, N. R., de Roode, S. R., de Rooy, W., Sandu, I., Xiao, H., and Xu, K. -M. Single-Column Model Simulations of Subtropical Marine Boundary-Layer Cloud Transitions Under Weakening Inversions: SCM SIMULATIONS OF CLOUD TRANSITIONS. United States: N. p., 2017. Web. doi:10.1002/2017MS001064.
Neggers, R. A. J., Ackerman, A. S., Angevine, W. M., Bazile, E., Beau, I., Blossey, P. N., Boutle, I. A., de Bruijn, C., Cheng, A., van der Dussen, J., Fletcher, J., Dal Gesso, S., Jam, A., Kawai, H., Cheedela, S. K., Larson, V. E., Lefebvre, M. -P., Lock, A. P., Meyer, N. R., de Roode, S. R., de Rooy, W., Sandu, I., Xiao, H., & Xu, K. -M. Single-Column Model Simulations of Subtropical Marine Boundary-Layer Cloud Transitions Under Weakening Inversions: SCM SIMULATIONS OF CLOUD TRANSITIONS. United States. doi:10.1002/2017MS001064.
Neggers, R. A. J., Ackerman, A. S., Angevine, W. M., Bazile, E., Beau, I., Blossey, P. N., Boutle, I. A., de Bruijn, C., Cheng, A., van der Dussen, J., Fletcher, J., Dal Gesso, S., Jam, A., Kawai, H., Cheedela, S. K., Larson, V. E., Lefebvre, M. -P., Lock, A. P., Meyer, N. R., de Roode, S. R., de Rooy, W., Sandu, I., Xiao, H., and Xu, K. -M. 2017. "Single-Column Model Simulations of Subtropical Marine Boundary-Layer Cloud Transitions Under Weakening Inversions: SCM SIMULATIONS OF CLOUD TRANSITIONS". United States. doi:10.1002/2017MS001064.
@article{osti_1411907,
title = {Single-Column Model Simulations of Subtropical Marine Boundary-Layer Cloud Transitions Under Weakening Inversions: SCM SIMULATIONS OF CLOUD TRANSITIONS},
author = {Neggers, R. A. J. and Ackerman, A. S. and Angevine, W. M. and Bazile, E. and Beau, I. and Blossey, P. N. and Boutle, I. A. and de Bruijn, C. and Cheng, A. and van der Dussen, J. and Fletcher, J. and Dal Gesso, S. and Jam, A. and Kawai, H. and Cheedela, S. K. and Larson, V. E. and Lefebvre, M. -P. and Lock, A. P. and Meyer, N. R. and de Roode, S. R. and de Rooy, W. and Sandu, I. and Xiao, H. and Xu, K. -M.},
abstractNote = {Results are presented of the GASS/EUCLIPSE single-column model inter-comparison study on the subtropical marine low-level cloud transition. A central goal is to establish the performance of state-of-the-art boundary-layer schemes for weather and climate mod- els for this cloud regime, using large-eddy simulations of the same scenes as a reference. A novelty is that the comparison covers four different cases instead of one, in order to broaden the covered parameter space. Three cases are situated in the North-Eastern Pa- cific, while one reflects conditions in the North-Eastern Atlantic. A set of variables is considered that reflects key aspects of the transition process, making use of simple met- rics to establish the model performance. Using this method some longstanding problems in low level cloud representation are identified. Considerable spread exists among models concerning the cloud amount, its vertical structure and the associated impact on radia- tive transfer. The sign and amplitude of these biases differ somewhat per case, depending on how far the transition has progressed. After cloud breakup the ensemble median ex- hibits the well-known “too few too bright” problem. The boundary layer deepening rate and its state of decoupling are both underestimated, while the representation of the thin capping cloud layer appears complicated by a lack of vertical resolution. Encouragingly, some models are successful in representing the full set of variables, in particular the verti- cal structure and diurnal cycle of the cloud layer in transition. An intriguing result is that the median of the model ensemble performs best, inspiring a new approach in subgrid pa- rameterization.},
doi = {10.1002/2017MS001064},
journal = {Journal of Advances in Modeling Earth Systems},
number = 6,
volume = 9,
place = {United States},
year = 2017,
month =
}
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