Subject: Manilla station (MANB) / Tsunami Dec 26, 2004 ?
From: Pascal Willis <[email-masked]>
To: IDS_Analysis_Forum <[email-masked]>
Date: Tue, 7 Jun 2005 07:58:56 -0700

Dear colleagues,

the Manilla station (MANB) experienced some technical problems in 
second half of 2004 so we stopped processing these data (see full 
reports in DORISReports for details 
http://listes.cls.fr/wws/arc/dorisreport). This problem as well as 
problems with other DORIS stations is also fully documented in

Defining a DORIS core network for Jason-1 precise orbit determination 
based on ITRF2000, Methods and realization, P. Willis. J.C. Ries, J. 
Geod., 2005

I have recently reprocessed the available MANB data after its restart 
(Jan 27, 2005) and the data quality is now very much improved. The 
station signal is now received by all satellites (instead of only 
ENVISAT as before).

However, you will see on the attached plot that there is significant 
discontinuity in the latitude determination (+6cm) that could be 
explained either due the effect on the large Earthquake related to 
the Tsunami of December 26, 2004 or to some antenna centering or 
stability issue of the MANB DORIS antenna following construction work 
on the roof in October 2004.

A similar discontinuity can also be seen in the LEGOS/CLS monthly 
solution in January 2005 (but only based on 5 days of data).

For your information, CNES has decided to send a survey team soon on 
site to check this antenna and an IGN team should go there soon to do 
a new survey and check the antenna.

As it is seems that the DORIS data quality is good after Jan 27, 2005 
and that the related results could have some geophysical interest, we 
plan to resubmit the recent IGN/JPL weekly solutions including this 
time the MANB results. A DORISMail will be issued later on when these 
results are available at CDDIS to inform a broader audience.

Best regards
Pascal
-- 
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]