Archive for 2010

Eumetsat Meteo Satellite Conference

Wednesday, September 22nd, 2010

I just attended the Eumetsat Meteo Satellite Conference in Cordoba, Spain at a beautiful location right by the Mezquita.

The event brings together many satellite Meteo researchers. As you know most Meteorological satellites carry on-board many different scientific instruments, and this conference brings together a very heterogeneous group of scientific people which as very informative and useful to put our GNSS engineering work into context.

I was sent to the conference to present the GSN poster. The GSN is a support service that i have been a part of since 2003 through initial study, conceptual design, implementation, launch, improvements and maintenance. It provides Eumetsat with support GPS products on a very strict time basis to process the Metop satellite GRAS radio occultation instrument. The poster can be seen below, Enjoy!

It was a fun short trip and I am glad to be able to represent the GSN project in this international conference.

IGS Workshop 2010

Thursday, July 1st, 2010

Let me share with you my two presentations at the IGS Workshop, 2010 held in Newcastle in 2010.

I gave a presentation on the overall state of the IGS Infrastructure up and down the Rinex data chain, considering both the challenges faced by the station operators, the data centers and the Analysis Centers.

The second talk was on the way to confront the infrastructure challenges in the next two years or so.

The workshop was a very well organised affair, we had very interesting sessions and dedicated meetings.

IGS Station Height Tests

Saturday, March 13th, 2010

Monitoring the Sky for Astronomy with GPS

Saturday, February 6th, 2010

SAC has continued to support the IAC (Instituto Astrofisico de Canarias) by calculating the Precipitable Water Vapor (PWV) at the Observatorio Roque de los Muchachos (ORM) in La Palma. The island of La Palma is about 250 Km from Gran Canaria where SAC is based, both in the archipelago of the Canary Islands, Spain, of course, and both beautiful places!!

There is a public GPS station at the ORM established since 2001 by the IGN-E (Instituto Geográfico Nacional de España) , with the designation LPAL, as part of the coordinate system definition for the Canary Islands and as part of the regional EUREF project. The station’s historical data is available as part of the EUREF permanent network.

Using precise orbits from the IGS Final products the data from a network of stations including LPAL has been solved to extract the Tropospheric Zenith Delay (TZD) at the ORM every two hours for a period of 10 years from 2001 to the end of 2009. The TZD is used to calculate the PWV as described in the enclosed published paper and presentation which the IAC have produced with SAC’s help. I encourage you to download and read the paper below:


The IAC have concluded that the PWV time series produced by SAC for the ORM is correct by correlating with independent radiometer observations that had been undertaken at the ORM during several weeks in 2001 and 2002. The level of correlation of the GPS PWV data to the local radiometer measurements is around 93%, thus confirming the very high-quality of the calculations undertaken by SAC with the LPAL GPS data. As a ‘control’ location SAC included in the calculations also the permanent station MKEA in Mauna Kea, Hawaii, the site of many astronomical Observatories as the ORM is, and the correlation was also very high with independent measurements from Hawaii.

This has lead the IAC to be able to conclude that in terms of PWV content in the atmosphere (a very significant determinant of sky clarity for ground-based infrared astronomical observations), the ORM is of similar quality than Mauna Kea, a location some 1300 m higher in elevation, you can read the conclusions in the pdf above.

To finalise the PWV study of the ORM SAC and the IAC came together recently and made a short presentation to explain to the rest of the IAC what we have done in this study pf the PWV at the ORM. You can find the presentation below.

IGS Infrastructure Committee / Comité de Infraestructura del IGS

Saturday, January 9th, 2010