Subject: DORIS break in STJB
From: Pascal Willis <[email-masked]>
To: Martine Feissel <[email-masked]>
Cc: Jean-Francois Cretaux <[email-masked]>, John Ries <[email-masked]>, Ramesh Govind <[email-masked]>, Ad�le Guitart <[email-masked]>, Herve Fagard <[email-masked]>, Serguei Kuzin <[email-masked]>, Jean-Michel Lemoine <[email-masked]>, Jean-Jacques Valette <[email-masked]>, Jean-Paul Berthias <[email-masked]>, Pascal Willis <[email-masked]>, [email-masked], Zuheir Altamimi <[email-masked]>, Urs Hugentobler <[email-masked]>, Petr Stepanek <[email-masked]>, Jean-Pierre Granier <
Date: Fri, 12 Mar 2004 08:39:11 -0800

Dear Martine,

I think there could still be a missing break in the DORIS time series 
that is not mentioned and for which I would like to get some 
feed-back from the other Analysis Centers and/or from the SIMB :

January 20, 2003 	STJB	-1.7 cm in vertical

The change is small and hardly visible in the time series (see 
attached plot of residuals before putting any break) but without a 
break the estimated vertical velocity is -10 mm/yr, while with the 
break it goes down to -5 mm/yr and the residuals series has much less 
signal in it. The fact that the estimated horizontal displacements 
are within 1-2 mm makes me now think that this vertical discontinuity 
may be real.

I am not aware of any hardware intervention at this site from the SIMB.

If there is some agreement with the other Analysis centers, I could 
consider resubmitting the DORIS time series since 2003/1/20 with the 
correct DOMES description in the data file, if needed.

I have no problem with the other information in file 
doris_breaks.sinex as this is exactly what I gave to Zuheir. But has 
it been confirmed by somebody else as suggested in my 2003 
presentation at the IDS workshop?

Best regards
Pascal

NB:
for Fairbanks the earthquake was on Nov 3, 2002
for Arequipa, the earthquake was on Jun 23, 2001

-- 
Pascal Willis
Jet Propulsion Laboratory, MS 238-646     Ph : 1-818-393-4748
4800 Oak Grove Drive                      FAX: 1-818-393-4965
Pasadena CA 91109                         Em : [email-masked]