Objectives of the Working Group
The GCSS (GEWEX
Cloud System Study) Boundary
Layer Cloud Working Group aims to improve physical parameterizations
of clouds and cloud related processes, and their interactions. We
conduct careful intercomparisons between observational or laboratory
case studies, 3D large-eddy-simulation models, single-column-model
(SCM) versions of climate and numerical weather prediction (NWP) models
of cloud-topped boundary layers. Most of the leading groups modelling
boundary layer clouds have participated in our annual workshops, held
every 12-18 months.
The BLCWG is currently chaired by Adrian Lock of the Met Office, UK.
How to join
If you would like to keep in touch with our activities, you can join our email
list. Instructions on how to do this are here. Recent
announcements
| 13th January 2010 | Email of activities currently planned for 2010. |
| 22nd December 2009 (updated 13th Jan) |
Announcement of a workshop on the CGILS cloud feedback intercomparison case at Stony Brook University, New York, 1-2 March 2010 |
| 22nd July 2009 | Brief summary of outcomes of particular relevance to this group from the joint meeting with CFMIP, 8th - 12th June 2009, at the University of British Columbia in Vancouver. Also see the meeting webpage for more details. |
| 25th February 2009 | Announcement of the cloud feedback intercomparison case for discussion at a GCSS-CFMIP meeting in Vancouver in June 2009 |
| 19th June 2008 | A summary of the current and future GCSS BL cloud working group activities, as discussed at the 2008 Pan-GCSS Meeting, is available from here |
Current GCSS BLCWG activities
-
BL cloud climate change response:
CGILS
- Case coordinator: Minghua Zhang of Stony Brook University, NY
- Case specifications.
- First discussions of results at the joint meeting with CFMIP, 8th - 12th June 2009, at the University of British Columbia in Vancouver
- Focussed workshop 1st-2nd March 2010
- Partly as an outcome of both the RICO precipitating trade cumulus and DYCOMS II RF02 nocturnal drizzling stratocumulus intercomparison cases, there is a strong need for simple cases that can evaluate microphysics schemes used in GCM's in isolation so as to disentangle errors due to dynamics and errors due to microphysics.
- A GCSS Microphysics activity has been set-up, coordinated by Ulrike Lohmann of the Institute for Atmospheric and Climate Science, Switzerland.
- There will be a Microphysics workshop at University of Washington, Seattle, 24-25th June 2010 including discussion of stratocumulus and shallow cumulus cases.
- Case coordinators: Margreet van Zanten (LES) and A. Pier Siebesma (SCM) of KNMI.
- Case specifications. Initial submissions were due 1 September 2006. A revised case specification will be released in October 2006 and new submissions are welcome.
- All presentations from GCSS/GPCI/RICO workshop at GISS, NYC, Sept. 2006, including preliminary results from RICO case and RICO observational presentations.
(CFMIP-GCSS Intercomparison of Large-Eddy and Single-Column Models)
Related links to current GEWEX activities
- GABLS (the GEWEX Atmospheric Boundary Layer Study), whose mission is to coordinate research on boundary layer physics to improve the representation of the atmospheric boundary layer in numerical models.
- GPCI (the GCSS Pacific Cross-Section Intercomparison), which is comparing the observed thermodynamic structure and clouds along a vertical cross-section from the California coast to the central Pacific ITCZ during July 1998 and 2003 with simulations from regional and global simulations.
- An Ad Hoc activitity called DIME has the goal to provide "test kits" for model evaluation based on the GCSS Model Intercomparison Projects, including detailed results from the participating Cloud Resolving Models. William Rossow, NASA, GISS, is the chairperson.
