Minutes of the Meeting of the

CCSM SSC and Working Group Co-Chairs

Thursday, 26 June 2003

The Village at Breckenridge



1. Reflections on CCSM. Kiehl stated that management of the CCSM project was a challenge. He also stated that more people are needed to look at and analyze the model results.


2. Vision of CCSM. Collins, as the new incoming SSC Chair, discussed his roadmap for the future of CCSM. He stated that we would do climate sensitivity studies using the IPCC studies, process studies from GFDL and CPT collaborations, studies of high-resolution and "benchmark" calculations, and new physics and dynamics from the near-term Science Plan. We will integrate chemistry and climate into CCSM, such as ocean and land biogeochemistry, prognostic aerosols, tropospheric chemistry, WACCM, and tracers.


The Implementation Plan will be a Web document that reports on the status of the project; the relationship of the project to NCAR plans; and near-term priorities for hiring, education and outreach program, and university grants.


He will initiate an online CCSM Project Report that shows progress on near-term and long-term goals, science and technical highlights of the project, and information on educational outreach and collaborations.


To develop the next CCSM generation of scientists, we need to target postdoctoral and graduate students and increase the number of visiting scientists that are collaborating on CCSM. Some mechanisms to do this are through existing NCAR education programs, such as ASP, and creating interest for new funding from NSF.


Fung suggested development of a graduate student course on climate modeling that many could use, and she thought that could help with recruitment issues also by identifying student's who are interested.


Chris Bretherton said we could look at finer scale modeling, downscaling, and exploring physics at higher resolution. Ruby Leung is interested in the downscaling and upscaling issues, and Rasch suggested combining independent groups on these issues.


Sundquist suggested we look at lower resolution models also, but the Paleoclimate Working Group has now stated that T42 will work for them.


A new Chemistry Climate Working Group could be formed in 2004. A core group of scientists have already met to start a chemistry climate interest group and are working now on a specific collaborative project. They will meet again in February 2004.


Other ways to discover scientific interest in CCSM would be the NCAR Early Career Scientist Forum and the Earth System Sciences International Postdoctoral Network.


McKenna stated that ACD is hosting an emissions workshop this summer.


3. Working Group Co-Chairs' Needs and Concerns.


Atmosphere: Collins stated that the AMWG is interested in going to higher resolution.


Ocean: Large stated that the OMWG would like a frozen version of the CCSM for a while and that the OMWG needs software engineering help to provide a low-resolution atmosphere model and other components and to be able to run the model at other computing centers.


CCSM needs help from its working group members on analyzing the coupled runs. Taylor replied that the wider community should be able to help with model tuning and have access to model output to provide feedback.


Software Engineering: Craig stated that CPL6 is documented and ready and will be posted on the web soon.


Biogeochemistry: This group requested a formal process/procedure on how to port the code. Collins, Merilees, and Craig will discuss this further with Fung.


Land: Bonan stated that because the CLM is a community effort, no single scientist is familiar with the complete contents of the code, and Keith Oleson is writing the technical description and hopes to have it drafted in the November-December 2003 timeframe. The ocean and ice technical descriptions are easily updated when the dynamical core is decided. The atmosphere technical description is being updated to reflect the changes to the radiation scheme.


The IPCC version of CCSM code release is expected this fall. The freezing of this version of the model means the physics are frozen, a 1000-year control simulation is completed, and the User's Guide and technical descriptions are written and posted on the web. The vectorization of the model will also be going on during this time. We should plan to release the code to the community at least 5 months before next year's annual workshop, which is in early July, so probably release in the January to February 2004 timeframe.


Bader stated that OMB charged DOE with providing a high-resolution climate model (T85, T170) by the end of FY03 and it must be delivered.


CCWG: This group's plans for IPCC are a 20th century stabilization run with all forcings, a 21st century run of A2 or A1B to 2100, and a 21st century run of B2/B1 with emissions vs. concentrations. Community runs are A2, B2, A1B, B1, A1F1. Experiments that will be run are absorbed aerosols and indirect sulfate aerosol effects, time and space evolving emissions, and coupled WACCM model.


The decision on which dynamical core (spectral Eulerian/finite volume) will be used in CCSM must be made by the end of this summer. If the finite-volume model is not ready by the end of this summer, it will be off the table for IPCC version consideration.


Collins will keep the SSC and Working Group Co-chairs up-to-date on results of simulations using both dynamical cores.


Fein reported on the funds that are available through the NSF SGERs and also the regular NSF grant process.


4. Should we do another CCSM Journal of Climate Special Issue? Collins agreed to contact Dave Randall about another special issue and to let the SSC and Working Group Co-Chairs know what he says. If we do another special issue, the timeline will need to be distributed. Another journal we could consider is PNAS because they promise a 6-month turnaround for publication.


SSC and CAB Attendees: WG Co-Chair Attendees:
Jeff Kiehl Leo Donner
Bill Collins Phil Rasch
Chris Bretherton Rick Smith
Jim Hack Dick Moritz
Bill Large Elizabeth Hunke
Maurice Blackmon Marika Holland
Cecilia Bitz Gordon Bonan
Danny McKenna Bette Otto-Bliesner
Scott Doney Lisa Sloan
Jay Fein Jim Hurrell
Dave Bader Mike Alexander
Phil Merilees Inez Fung
Eric Sundquist Natalie Mahowald
Isaac Held Jerry Meehl
John Drake Karl Taylor
Francis Bretherton Ben Santer
Lydia Shiver Tony Craig
  Cecelia DeLuca
  Pat Worley