From murphy@nmsu.edu Mon May 10 10:17 MDT 1999 Received: from cedar.hao.ucar.edu (cedar.hao.ucar.edu [128.117.16.90]) by jabba.hao.ucar.edu (8.9.0/8.9.0) with ESMTP id KAA11862 for ; Mon, 10 May 1999 10:17:25 -0600 (MDT) Received: from ncar.UCAR.EDU (ncar.ucar.edu [128.117.64.4]) by cedar.hao.ucar.edu (8.9.0/8.9.0) with ESMTP id KAA15226 for ; Mon, 10 May 1999 10:17:24 -0600 (MDT) Received: from bubba.NMSU.Edu (bubba.NMSU.Edu [128.123.3.39]) by ncar.UCAR.EDU (8.9.1a/) with ESMTP id KAA04157 for ; Mon, 10 May 1999 10:17:22 -0600 (MDT) Received: from dns1.NMSU.Edu (dns1.NMSU.Edu [128.123.3.5]) by bubba.NMSU.Edu (8.9.2/8.9.0) with ESMTP id KAA00919; Mon, 10 May 1999 10:17:17 -0600 (MDT) Received: from atmos.NMSU.Edu (atmos.NMSU.Edu [128.123.26.194]) by dns1.NMSU.Edu (8.9.3/8.9.0) with ESMTP id KAA29980; Mon, 10 May 1999 10:17:18 -0600 (MDT) Received: from localhost (murphy@localhost) by atmos.NMSU.Edu (8.9.0/8.9.0) with SMTP id KAA24273; Mon, 10 May 1999 10:17:15 -0600 (MDT) X-Authentication-Warning: atmos.NMSU.Edu: murphy owned process doing -bs Date: Mon, 10 May 1999 10:17:15 -0600 (MDT) From: Jim Murphy X-Sender: murphy@atmos To: Jim Schaeffer , foster@ncar.ucar.edu, sbougher@lpl.arizona.edu cc: murphy@nmsu.edu Subject: TGCM / MGCM coupling Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Content-Length: 3577 Status: R TO: Ben Foster (NCAR) and Jim Schaeffer (NASA Ames) FROM: Jim Murphy (NMSU) RE: interactive coupling of the Mars TGCM and MGCM DATE: 11 May, 1999 Hello Ben and Jim, I am incredibly delinquent in getting this message out and I apologize to you both and to Steve Bougher. Our ongoing effort at coupling Steve's Thermospheric Mars GCM (TGCM) and the NASA Ames Mars GCM (MGCM) requires the expertise that you each possess with your respective codes. To date, our coupling efforts have been 'offline'. In this mode, time and zonal mean fields (geopotential and temperature of a given pressure surface) and time-of-sol geopotential variations (thermal tidal variations) have been obtained from the MGCM for some specified time interval (10 sols), and these values have been used as a lower boundary condition to drive the TGCM. These experiments have been illuminating. However, as became apparent during the aerobraking process for the Mars Global Surveyor spacecraft, which dipped down to ~110 km altitude within the atmosphere, there is an incredible amount of structure in the atmospheric fields at these heights (pressures), much of which is not captured by our to-date simple model coupling. Therefore we have undertaken, and are being funded by NASA's Planetary Atmospheres Program, to improve the sophistication of the coupling between the TGCM and MGCM. This new coupling is envisioned to be fully interactive, whereby fields of importance (geopotential, temperature, wind, and possibly others) are passed both upward and downward across the interface (pressure) level at which the models are joined. Thus far, this level has been the 0.32 microbar level (~70 km above the surface). In order to move this process along, we would like the two of you to spend a day or two together to brainstorm the most effective route to follow to develop this interactive coupling. The two of you can talk with each other and decide where you would like this get-together to take place, and when. Sooner would be preferable, but my tardiness in getting this message out to you puts me in no position to force this issue. Currently, the MGCM is undergoing a number of upgrades / improvements, including possibly the inroduction of a new horizontal grid-structure. However, the general framework of the model will remain the same (I think this is true, Jim...am I mistaken?), thus I do not believe that this get-together needs to wait for these improvements to be completed. Steve and I can certainly provide some input prior to your meeting, but I'm sure the most progress will be accomplished when you all can sit down and talk models. Below I list the contact info for both Jim and Ben. I hope you can get in touch with each other this week and set up a time to get together. If you have any questions, please let me know (murphy@nmsu.edu; 505-646-5333) and I'll get an answer to you quickly, or will have Steve do so if it is better answered by him. I'm looking forward to getting a coupled model developed, and hope you are also. Best Regards, Jim Murphy CONTACTS: Ben Foster National Center for Atmospheric Research High Altitude Observatory Boulder, CO 80307-3000 (303)-497-1595 foster@ncar.ucar.edu Jim Schaeffer NASA Ames Research Center MS 245-3 Moffett Field, CA 94035-1000 jschaef@hellas.arc.nasa.gov (650) 604-6078 ____________________________________ Jim Murphy Assistant Professor Department of Astronomy New Mexico State University murphy@nmsu.edu (505) 646-5333 FAX (505) 646-1602