Floods in Pakistan as detected by SMOS

Category : Cal/Val, L2

Since the end of July Northern Pakistan has been affected by the worst floods in living memory – according to government figures almost 14 million people have been affected.The United Nations believes 1,600 people have already died due to the floods. The magnitude of the disaster is so important that flooding can be followed by SMOS. The following pictures show Pakistan soil moisture map at previous and post disaster.

SM_OPER_MIR_SMUDP2_20100717T133052_20100717T142454_308_002_1 SM_OPER_MIR_SMUDP2_20100728T003212_20100728T012611_308_001_1 Legend
SM_OPER_MIR_SMUDP2_20100730T132504_20100730T141856_308_001_1 SM_OPER_MIR_SMUDP2_20100804T133020_20100804T142419_308_001_1

All soil moisture maps available over Pakistan between the 1st of July and two days ago, were put on Google Earth. The time series clearly shows changes at the end of July with increase of soil moisture values. The affected area are very well captured by the soil moisture maps and in accordance with the disaster maps are provided by the International Disaster Charter activated the 1st August 2010. The high temporal frequency and the ability to « see » through clouds allow to SMOS to provided crucial information in this case, despite its low resolution. The significant topography does not seem to be a major limitation for soil moisture retrievals in this particular case.


So even though has a coarse spatial resolution it seems to be compensated by the all weather and frequent acquisition. It is also expected that, once the retrieval algorithms are tuned and fully validated, such information could be used to infer more accurately the actual extend of the flooding helping both to improve locally weather forecasts and possibly provide useful information for the relief team on the ground.

GEVisible on Google Earth

Bad Guys : we know where you are!

Category : Commissioning phase, Data, L1

Smos is operating at L Band in a protected window i.e., 1400-1427 MHz. This means that emission are FORBIDDEN in this wave band.

Never the less, as some « people  » are careless, selfish etc, they do not bother and tend to spill into the protected band (by being very close and not filtering adequately) so for SMOS we only use a limited part of the allocated frequency band reducing the sensitivity (as usual the selfishness of a few is detrimental to many!)

So that is a nuisance but we can deal with it.

But some are more naughty. They do not bother about harmonics (700 MHz UHF TV band for instance) and do have thus illegal emission in the protected band. They can cause severe problems at ground level

The most noxious and nasty are those who deliberately emit (and usually with huge power) in the protected band….

The first SMOS data give an idea of those polluters and threat to all the potential and useful applications of L band data The map below provided by the L1PP team at ESAC shows in red all the potential large illegal emitters.

We are working on the data and will either better focus in some cases (as soon as the sources are better identified) as already done for many, and suppress the « tails »,  as well as get rid of any potential artifact. Once all is validated we will publish the map. and start considering more potent actions towards the relevant organizations.

In the mean time you can see that some areas are – with the current algorithms – totally beyond reach for SM retrievals.


Global View of RFI sources ( red dots or ... areas)

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Première synthèse SM

Category : Commissioning phase, L2

Le DPGS a commencé à produire des niveau 2 aujourd’hui. Les données sont disponibles sur le ftp.
Toujours avec un étalonnage très imparfait, et pas mal de petits problèmes, mais enfin, elle est la:

Synthèse SM

L’instrument sera rebooté aujourd’hui, pour tenter de le purger de toute la mauvaise humeur accumulée ces derniers jours.

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