IDS activity report 2011 - International DORIS Service

10.4 FIRST CRYOSAT-2 ANALYSESAt the end of 2011, 6 ACs (esa, gau, gop, gsc, ign and lca) deliver multi-satellite solutionsincluding Cryosat-2. Cryosat-2, which was launched on April 2010, is the second DORISsatellite with the new DGXX DORIS receiver onboard (the first one was Jason-2). Theanalyses of these new series shown that adding Cryosat-2 has no major impact on the series interms of transformation parameters (see for example Figure 9).Figure 9. Impact of Cryosat-2 on ESA solutions.Two reasons can explain that Cryosat-2 has no such impact as Jason-2:1. Cryosat-2 altitude (717 km) is lower than Jason-2 (1,336 km) so the 7 channels of theDORIS receiver are less used.2. Cryosat-2 orbit inclination (92°) is closer than Jason-2 (66°) to the other 3 DORISsatellites (98°) used in the combined solutions.Due to its polar orbit, the major impact of Cryosat-2 should be on the DORIS stationspositions located at high latitude. This topic is planned to be studied in 2012 by the IDS CC.10.5 COMMUNICATIONSThe IDS Combination Center joined both EGU and AGU fall meetings where it presented,respectively, an oral presentation titled “Research activities for continued improvement in theDORIS contribution to the reference frame” (Session G2.4), and the poster “Impact of Jason-2and Cryosat-2 on DORIS combination” (Session G53A ).43