Date: Thu, 17 Jun 2004 
From: Frank.Lemoine@ga.gov.au 

(...)

Regarding Envisat I would like clarification as to what the CNES
(Jean-Paul) and ESA are using for the DORIS offset on ENVISAT. 

We *don't* use the corrections on The DORIS data, and we see an offset
in scale when we test an Envisat time series with ITRF2000 of +35 mm. 

We apply the offset
OFFSET       -7.052         -1.085       -1.725 (x,y,z meters) 
which we obtained from CNES documentation on SPIKE. The analysis by 
John Dawson here at GA implies this offset should be -1.76 at least 
maybe even -1.79. 

Could there be a typo in the documentation file that is on SPIKE? 
We apply our own offsets on TOPEX and SPOT-2 and have no problems, 
so somehow the information on ENvisat seems anomalous.

Kind regards,

Frank Lemoine