Received: from cluster-jaune.cls.fr (cl1-jaune.cls.fr [91.207.20.90]) by sympa-ext.cls.fr (8.13.1/8.13.1) with ESMTP id p18LRBEL028489 for ; Tue, 8 Feb 2011 21:27:11 GMT Received: by cluster-jaune.cls.fr (Postfix) id 375E354EE7; Tue, 8 Feb 2011 21:27:11 +0000 (GMT) Delivered-To: ids.analysis.forum@ids-doris.org Received: from cluster-d.mailcontrol.com (cluster-d.mailcontrol.com [85.115.60.190]) by cluster-jaune.cls.fr (Postfix) with ESMTP id 1F86B2770F for ; Tue, 8 Feb 2011 21:27:11 +0000 (GMT) Received: from ndjsnpf02.ndc.nasa.gov (ndjsnpf02.ndc.nasa.gov [198.117.1.122]) by rly25d.srv.mailcontrol.com (MailControl) with ESMTP id p18LR55k032422 for ; Tue, 8 Feb 2011 21:27:07 GMT Received: from ndmsppt03.ndc.nasa.gov (ndmsppt03.ndc.nasa.gov [198.117.0.102]) by ndjsnpf02.ndc.nasa.gov (Postfix) with ESMTP id EC5E7A8651 for ; Tue, 8 Feb 2011 15:27:03 -0600 (CST) Received: from ndmshub03.ndc.nasa.gov (ndmshub03-pub.ndc.nasa.gov [198.117.0.42]) by ndmsppt03.ndc.nasa.gov (8.14.3/8.14.3) with ESMTP id p18LR3iD017002 for ; Tue, 8 Feb 2011 15:27:03 -0600 Received: from NDMSSCC02.ndc.nasa.gov ([198.117.2.168]) by ndmshub03.ndc.nasa.gov ([198.117.2.162]) with mapi; Tue, 8 Feb 2011 15:27:03 -0600 From: "Lemoine, Frank G. (GSFC-6980)" To: "ids.analysis.forum@ids-doris.org" Date: Tue, 8 Feb 2011 15:25:42 -0600 Thread-Topic: Sensitivity of GRACE vs LAgeos for deg 2 terms (forwarded) Thread-Index: AQHLx9br1WKrctgE00CCtRnsvmsdRw== Message-ID: Accept-Language: fr-FR, en-US Content-Language: fr-FR X-MS-Has-Attach: X-MS-TNEF-Correlator: acceptlanguage: fr-FR, en-US Content-Type: text/plain; charset="iso-8859-1" MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:5.2.15,1.0.148,0.0.0000 definitions=2011-02-08_05:2011-02-08,2011-02-08,1970-01-01 signatures=0 X-Mailcontrol-Inbound: vDhBN9DbDAmsHR1rhk2nWmhmz2zQyNKrNKaQ3LZxmP91GmsDC50eqQ== X-Spam-Score: -2.3 X-Scanned-By: MailControl A_10_80_00 (www.mailcontrol.com) on 10.68.0.135 Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by sympa-ext.cls.fr id p18LRBEL028489 X-Validation-by: lsoudarin@cls.fr Subject: [ids.analysis.forum] Sensitivity of GRACE vs LAgeos for deg 2 terms (forwarded) Dear IDS Analysis Forum. I forward the following email on the same thread as earlier today. F. Lemoine ************************************************************** ************************************************************** ________________________________________ De : John C. Ries [ries@csr.utexas.edu] Date d'envoi : mardi 8 février 2011 15:18 À : E Schrama; Lemoine Jean-Michel Objet : Re: RE : Long term trends in the gravity field At 12:46 PM +0100 2/8/11, E Schrama wrote: >Dear all, > >This is a most interesting discussion. Is a GRACE+Lageos solution >for C21/S21 not the same as saying that you have a Lageos only >solution for these terms? Is GRACE capable of observing these degree >2 order 1 terms at all? > >Ernst > Hi Ernst, My impression is that SLR and GRACE both do well for C21/S21. GRACE only seems to have problems with C20, not the other degree-2 terms. We've done a number of SLR solutions for C21/S21. We've used 5 satellites to determine a 3x3 and 5x5 gravity field (Minkang Cheng did these) and I've done individual and combined LAGEOS-1 and LAGEOS-2 solutions. C21/S21 are so well observed now that even a single LAGEOS satellite provides credible results. I found that individually, LAGEOS-1 and LAGEOS-2 gave identical results for S21, and similar results for C21 except for a difference in slope (this was in my 2009 Fall AGU poster). Best regards, John Cliquez sur l'url suivante https://www.mailcontrol.com/sr/2Qfpx4DpfmDTndxI!oX7Uqar2HCgETYdY+esYEnXPB0zwGwzmy2BD!gueKnV1gyE3HoUXzjm!9VTEf5tQBqpNg== si ce message est indésirable (pourriel).