Soon 8 candles for SMOS!! (2/8)

Category : Non classé, Satellite

After the first image it was obvious that SMOS was running smoothly but still more works had to be done. The Commissioning phase started. We were tasked to make the first products, validate them and select the final mode of operations. For instance two options were possible, dual or full polarisation. If full pol was attractive, it also meant a degradation of sensitivity. Luckily after many tests (SMOS was operated alternatively full and dual pol, one week each for enough time to be able to reach a decision) it was found that thanks to the instrument excellent performances ful pol was perfectly acceptable and was thus selected. But all was not nice. Over oceans reaching the hundredth of a K was challenging , stability was yet to … stabilize etc. For the former  J. Tenerelli suggested to use a diagnostic tool the so called OTT (Ocean Target Transformation) which was soon to become « the tool » over ocean surfaces. for the latter the instrument did stabilize in May. This is why we generally recommend to only use data from June 2010 for delicate studies. But all this was expected and did not come as a surprise. the surprises were really bad news…

First the local oscillators of one arm, once disturbed, did seem unable to relock and needed a complete reboot… not good. This was swiftly cured by using switch to the redundant (nominal actually) segment. Again business as usual. What was not was teh discovery of RFI (radio frequency interferences) in our protected band!!

We expected some perturbations and our algorithms all had a RFI detection scheme … what we did not expect is such a large quantities of sources !

DGG_CURR_RFI_20091215_20100117_BB_less_outliers-detection

Situation (RFI probability) in December 2009 – July 2010 (P Richaume)

This obviously needed some sort of an action! we started identifying, locating, reporting these bad guys. Some were out of band emissions, but too strong to be legal, some downright « outlaws ». emitting in band. The work was/is done by Colleagues at ESAC and at CESBIO while the  reporting is done through the ANFR and managed / coordinated by ESA with some success as in many areas the situation is significantly improved (North America, Greenland, western Europe, …). the « cleanest country is probably Australia while the darkest is Japan which changed in 2011 from rather OK to completely obscured by RFI. Japan is no more on the L band Map!

These findings enabled Aquarius to be prepared while SMAP could design a very sophisticated receiver able to reduce the impact of RFI on data.

But we have to be very careful many frequency greedy groups are also lurking in the background on top of those mentioned above… which could jeopardize the wealth of results L band radiometry ids offering us (more about this in the next posts) and which can be illustrated by the first ever Soil moisture – Ocean Salinity map ever produced from space .. thanks to SMOS

Image1Soil Moisture and Ocean salinity over the globe (August 2010) (F Cabot).

Note that since 2010 many progresses were made and we have much improved results by now… stay tuned!

Alexander Löw

Category : Non classé

Dear ColleaguesAlex-loew

I regret to have to tell you a very sad piece of information. One of our colleagues, Alex Löw tragically died in a car accident last week end. He had been with us since the inception of the Cal Val activities for SMOS and has always been very supportive of the passive microwave soil moisture approach. More important he was a very good scientist and we all enjoyed and gained by discussing science with him. He was also very pleasant man, always positive and smiling, never the last to have some fun and never taking himself too seriously. In short a very easy going but serious and enthusiastic colleague. I will for sure miss him a lot.

My deepest sympathy goes to his wife and children

Position opening at CESBIO

Category : Non classé, position opening

Position opening at CESBIO

In the framework of the SMOS (Soil Moisture and Ocean Salinity) follow on mission, the Centre d’Etudes Spatiales de la BIOsphère (CESBIO) is opening a position. The duration is 12 months with a possible extension.

SMOS was launched in 2009 and has been running very smoothly ever since (see here or on this blog). SMOS relies on the use of a new instrument: a 2 D interferometer to achieve both adequate spatial and temporal sampling and operates at L Band. It was followed by two other satellites SMAP and Aquarius with different observation modes but always operating at L band.

With these missions in flight, a wealth of science and applications has been derived ranging from hurricane or thin sea ice monitoring to drought or flood forecasting or climate monitoring.

It is however time to envision how to replace aging satellites and for this purpose the European Space Agency (ESA) initiated a study to define users’ requirements at low frequency passive microwaves.

The study was awarded to a European consortium led by CESBIO.  In this context CESBIO is opening a position to contribute to this project.

The role of the applicant is to basically participate within the consortium to the making of the project in the two main aspects:

Support management and coordination:

  • establish and operate web pages portal for both internal and external communication and management of the project activities
  • report and documentation
  • organise science meeting and write the related reports
  • liaise with ESA and the international members of the project

Support for technical studies depending on his skill:

  • contribute to establishing a list of the different products supported by L-Band measurements together with their accuracies and feasibility/ maturity from input of the community
  • Translate and trace requirements from science end users to requirements for geophysical parameters, and to passive L-Band products.
  • Contribute to a “cluster analysis” of products and applications according to their key requirements, like temporal and spatial resolution and radiometric accuracy
  • perform simulations to assess requirements when needed

Applicants should possibly hold a Ph.D. degree in remote sensing or should have equivalent experience in space research and in physics and geophysics. They should have good communication skills. The applicant should be fluent in English (written and spoken). A good practice is a plus. The applicant should have excellent  writing skills for reporting and documentation.

The work will take place within the SMOS team of CESBIO (Toulouse) and in collaboration with INRA (Bordeaux), several other teams in Italy, Spain, Switzerland, Finland, Portugal, as well ESA (Noordwijck NL) and CNES (Toulouse France).

Salary: Gross: about 2100 euros / month, depending on qualification and experience

Duration: 12 months minimum

Applications (application letter + CV+2 references) should be sent to Yann Kerr (Yann.kerr@cesbio.cnes.fr; phone: 05 61 55 85 22)

Happy New Year!!

Category : CATDS, Data, L2, Non classé, Satellite

The SMOS team wishes you all a very Happy, Healthy and Peaceful Year 2016!

Let it be full of good L band radiometer data as well !!

We are also pleased to announce that the reprocessing of the 6 years of SMOS data is quasi completed and is currently being checked. So more about the official release very soon together with new results!

All the best from the SMOS team

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