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Nemesio RODRIGUEZ FERNANDEZ

C

Université de Toulouse, CNES, CNRS, INRA, IRD, UPS

Des réseaux de neurones pour l’exploitation de bases de données multi-sources : application à la

télédétection et à l’assimilation de données

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Soil moisture remote sensing using passive microwaves

Cliquez pour modifier le style du titre

N. Rodríguez Fernández. Atelier Permanent de l’Observatoire Midi-Pyrénées, 7 nov 2017

Passive microwaves and soil moisture

Physical modeling, Radiative transfer, tau-omega model

Observation: brightness temperatures

Geo-physical variables: soil

moisture, vegetation optical depth, soil temperature, soil type, …

Kerr et al. (2012, IEEE Tran. Geo. Remote Sensing)

The drier the soil, the highest the brightness temperature (at constant

soil temperature)

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Au commencement était la donnée ...

Machine Learning for SMOS

N.J. Rodriguez-Fernandez, P. Richaume, Y.H. Kerr

Neural networks to obtain an added value from a multi-source data base

Long-time series Multi-sensor synergy

Acknowledgements These studies have been supported by the ESA -ECMWF SMOS contract, ESA support To Science Element SMOS+Neural Network, ESA SMOS Soil Moisture Expert Support Laboratory contract , by CNES (Centre National d’Etudes Spatiales) TOSCA program and by the French SMOS ground segment (CATDS).

ESA LPS– May 2019

Input: AMSR-E multi-frequency brightness temperatures

Target: SMOS CATDS Level 3 soil moisture Goal: Construct long-time series for climate data records of soil moisture

Reference : Rodriguez-Fernandez et al.

2016, Remote Sensing Data dissemination: CATDS

Near-real-time products

Pure data-driven retrievals Application for data assimilation

Centre d’Etudes Spatiales de la BIOsphère (CESBIO) CNES, CNRS, U. Toulouse, IRD, Toulouse, France

Input: SMOS Near-Real-Time multi-incidence angle brightness temperatures and ECWMF model soil temperature

Target:: SMOS ESA Level 2 soil moisture Goal: To retrieve soil moisture from SMOS observation in near-real time (less than 3.5 hours after sensing)

Reference : Rodriguez-Fernandez et al.

2017, Hydrology and Earth System Sciences Data dissemination: EUMETSAT

EumetCast, ESA SMOS dissemination portal

SMOS

Terra/Aqua

MODIS, AMSR-E Metop

ASCAT

Integrated Forecast System

In Situ

measurements

ECOCLIMAP Sand/clay

Input: SMOS Near-Real-Time multi-incidence angle brightness temperatures

Target: ECMWF H-TESSEL soil moisture in the first soil layer (0-7 cm) Goal: To compute from SMOS observation a soil moisture compatible with ECMWF model simulations for efficient data assimilation

Reference : Rodriguez-Fernandez et al. 2019, preprints.org (submitted to Remote Sensing)

Data assimilation: SMOS neural network soil moisture will be

assimilated operationally at ECMWF from cycle 46r1 (June 2019) Input: SMOS Near-Real-Time multi-incidence angle

brightness temperatures, MODIS NDVI, ECWMF model soil temperature

Target: in situ measurements of soil moisture

Goal: To retrieve soil moisture from SMOS observation with a neural network trained on in situ measurements. Retrieval independent of land surface models or radiation transfer computations

Reference : Rodriguez-Fernandez et al. 2017, IGARSS

Input: SMOS Near-Real-Time multi-incidence angle brightness

temperatures, MODIS NDVI, ECOCLIMAP sand/clay fraction, ASCAT backscattering

Target: ECMWF H-TESSEL soil moisture in the first soil layer (0-7 cm) Goal: To retrieve soil moisture extracting the synergies from passive (SMOS) and active (ASCAT) microwaves observations

Reference : Rodriguez-Fernandez et al. 2015, IEEE TGARS

Abstract

The Soil Moisture and Ocean Salinity (SMOS) satellite is an interferometric passive radiometer launched by ESA in 2009. After three year acquiring data, in 2012, the ESA Support to Science Element « SMOS + Neural Network » project started to study the use of machine learning techniques, in particular neural networks (NNs), to process SMOS data to estimate soil moisture. Since then, several

applications have been studied and successfully implemented operationally in the framework of different subsequent projects. All of these projects have in common the use of neural networks to exploit the synergies from multi-sources data bases containing data from passive microwave radiometers at different frequencies, active microwave scatterometers, optical/infrared reflectivities, numerical weather

prediction models, in situ measurements and static maps of soil and vegetation properties.

Nous avons beaucoup de données de sources diverses pour tester des techniques d’apprentissage automatique

D’abord il faut co-localiser les données dans le temps et dans l’espace: interpolations,

agrégation (résolutions différentes), re-échantillonnages,… souvent cette étape demande plus de temps que la phase d’apprentissage elle-même

Données:

• micro-ondes

passives et actives 1.4, 5.5, 10… GHz

• visible/infrarouge

• modèles transfert de rayonnement

• modèles de surface

• cartes statiques

• mesures de terrain

Données:

• pour établir des critères de filtrage

• comme données d’entrée

• pour tester les sorties du modèle statistique

RT models

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N. Rodríguez Fernández. Rencontres R&D Meteo France, 18 Juin 2019

Statistical retrievals using Neural Networks

NN soil moisture

Soil moisture examples

• SMOS Level 2 SM

• Radiation transfer models

• Surface models

• In situ measurements

Adapt NN weights

Test different input data

Training: comparison and new modeling step if needed

Input data: SMOS TBs, AMSR-E TBs, ASCAT s , MODIS NDVI,…

Depends on the goal !

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Feed forward network

Apprentissage supervisé en regression

Data filtering and sampling : training, validation, test

Multi-layer perceptron, network structure, best input data … Gradient backpropagation

Minimization of the MSE and regularization

Credit figure: Dreyfus et al. 2008, Ed. Eyrolles

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Feature extraction

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Output errors

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Machine Learning for SMOS

N.J. Rodriguez-Fernandez, P. Richaume, Y.H. Kerr

Neural networks to obtain an added value from a multi-source data base

Long-time series Multi-sensor synergy

Acknowledgements These studies have been supported by the ESA -ECMWF SMOS contract, ESA support To Science Element SMOS+Neural Network, ESA SMOS Soil Moisture Expert Support Laboratory contract , by CNES (Centre National d’Etudes Spatiales) TOSCA program and by the French SMOS ground segment (CATDS).

ESA LPS– May 2019

Input: AMSR-E multi-frequency brightness temperatures

Target: SMOS CATDS Level 3 soil moisture Goal: Construct long-time series for climate data records of soil moisture

Reference : Rodriguez-Fernandez et al.

2016, Remote Sensing Data dissemination: CATDS

Near-real-time products

Pure data-driven retrievals Application for data assimilation

Centre d’Etudes Spatiales de la BIOsphère (CESBIO) CNES, CNRS, U. Toulouse, IRD, Toulouse, France

Input: SMOS Near-Real-Time multi-incidence angle brightness temperatures and ECWMF model soil temperature

Target:: SMOS ESA Level 2 soil moisture Goal: To retrieve soil moisture from SMOS observation in near-real time (less than 3.5 hours after sensing)

Reference : Rodriguez-Fernandez et al.

2017, Hydrology and Earth System Sciences Data dissemination: EUMETSAT

EumetCast, ESA SMOS dissemination portal

SMOS

Terra/Aqua

MODIS, AMSR-E Metop

ASCAT

Integrated Forecast System

In Situ

measurements

ECOCLIMAP Sand/clay

Input: SMOS Near-Real-Time multi-incidence angle brightness temperatures

Target: ECMWF H-TESSEL soil moisture in the first soil layer (0-7 cm) Goal: To compute from SMOS observation a soil moisture compatible with ECMWF model simulations for efficient data assimilation

Reference : Rodriguez-Fernandez et al. 2019, preprints.org (submitted to Remote Sensing)

Data assimilation: SMOS neural network soil moisture will be

assimilated operationally at ECMWF from cycle 46r1 (June 2019) Input: SMOS Near-Real-Time multi-incidence angle

brightness temperatures, MODIS NDVI, ECWMF model soil temperature

Target: in situ measurements of soil moisture

Goal: To retrieve soil moisture from SMOS observation with a neural network trained on in situ measurements. Retrieval independent of land surface models or radiation transfer computations

Reference : Rodriguez-Fernandez et al. 2017, IGARSS

Input: SMOS Near-Real-Time multi-incidence angle brightness

temperatures, MODIS NDVI, ECOCLIMAP sand/clay fraction, ASCAT backscattering

Target: ECMWF H-TESSEL soil moisture in the first soil layer (0-7 cm) Goal: To retrieve soil moisture extracting the synergies from passive (SMOS) and active (ASCAT) microwaves observations

Reference : Rodriguez-Fernandez et al. 2015, IEEE TGARS

Abstract

The Soil Moisture and Ocean Salinity (SMOS) satellite is an interferometric passive radiometer launched by ESA in 2009. After three year acquiring data, in 2012, the ESA Support to Science Element « SMOS + Neural Network » project started to study the use of machine learning techniques, in particular neural networks (NNs), to process SMOS data to estimate soil moisture. Since then, several

applications have been studied and successfully implemented operationally in the framework of different subsequent projects. All of these projects have in common the use of neural networks to exploit the synergies from multi-sources data bases containing data from passive microwave radiometers at different frequencies, active microwave scatterometers, optical/infrared reflectivities, numerical weather

prediction models, in situ measurements and static maps of soil and vegetation properties.

Machine Learning for SMOS

N.J. Rodriguez-Fernandez, P. Richaume, Y.H. Kerr

Neural networks to obtain an added value from a multi-source data base

Long-time series Multi-sensor synergy

Acknowledgements These studies have been supported by the ESA -ECMWF SMOS contract, ESA support To Science Element SMOS+Neural Network, ESA SMOS Soil Moisture Expert Support Laboratory contract , by CNES (Centre National d’Etudes Spatiales) TOSCA program and by the French SMOS ground segment (CATDS).

ESA LPS– May 2019

Input: AMSR-E multi-frequency brightness temperatures

Target: SMOS CATDS Level 3 soil moisture Goal: Construct long-time series for climate data records of soil moisture

Reference : Rodriguez-Fernandez et al.

2016, Remote Sensing Data dissemination: CATDS

Near-real-time products

Pure data-driven retrievals Application for data assimilation

Centre d’Etudes Spatiales de la BIOsphère (CESBIO) CNES, CNRS, U. Toulouse, IRD, Toulouse, France

Input: SMOS Near-Real-Time multi-incidence angle brightness temperatures and ECWMF model soil temperature

Target:: SMOS ESA Level 2 soil moisture Goal: To retrieve soil moisture from SMOS observation in near-real time (less than 3.5 hours after sensing)

Reference : Rodriguez-Fernandez et al.

2017, Hydrology and Earth System Sciences Data dissemination: EUMETSAT

EumetCast, ESA SMOS dissemination portal

SMOS

Terra/Aqua

MODIS, AMSR-E Metop

ASCAT

Integrated Forecast System

In Situ

measurements

ECOCLIMAP Sand/clay

Input: SMOS Near-Real-Time multi-incidence angle brightness temperatures

Target: ECMWF H-TESSEL soil moisture in the first soil layer (0-7 cm) Goal: To compute from SMOS observation a soil moisture compatible with ECMWF model simulations for efficient data assimilation

Reference : Rodriguez-Fernandez et al. 2019, preprints.org (submitted to Remote Sensing)

Data assimilation: SMOS neural network soil moisture will be assimilated operationally at ECMWF from cycle 46r1 (June 2019) Input: SMOS Near-Real-Time multi-incidence angle

brightness temperatures, MODIS NDVI, ECWMF model soil temperature

Target: in situ measurements of soil moisture

Goal: To retrieve soil moisture from SMOS observation with a neural network trained on in situ measurements. Retrieval independent of land surface models or radiation transfer computations

Reference : Rodriguez-Fernandez et al. 2017, IGARSS

Input: SMOS Near-Real-Time multi-incidence angle brightness temperatures, MODIS NDVI, ECOCLIMAP sand/clay fraction, ASCAT backscattering

Target: ECMWF H-TESSEL soil moisture in the first soil layer (0-7 cm) Goal: To retrieve soil moisture extracting the synergies from passive (SMOS) and active (ASCAT) microwaves observations

Reference : Rodriguez-Fernandez et al. 2015, IEEE TGARS

Abstract

The Soil Moisture and Ocean Salinity (SMOS) satellite is an interferometric passive radiometer launched by ESA in 2009. After three year acquiring data, in 2012, the ESA Support to Science Element « SMOS + Neural Network » project started to study the use of machine learning techniques, in particular neural networks (NNs), to process SMOS data to estimate soil moisture. Since then, several

applications have been studied and successfully implemented operationally in the framework of different subsequent projects. All of these projects have in common the use of neural networks to exploit the synergies from multi-sources data bases containing data from passive microwave radiometers at different frequencies, active microwave scatterometers, optical/infrared reflectivities, numerical weather

prediction models, in situ measurements and static maps of soil and vegetation properties.

Machine Learning for SMOS

N.J. Rodriguez-Fernandez, P. Richaume, Y.H. Kerr

Neural networks to obtain an added value from a multi-source data base

Long-time series Multi-sensor synergy

Acknowledgements These studies have been supported by the ESA -ECMWF SMOS contract, ESA support To Science Element SMOS+Neural Network, ESA SMOS Soil Moisture Expert Support Laboratory contract , by CNES (Centre National d’Etudes Spatiales) TOSCA program and by the French SMOS ground segment (CATDS).

ESA LPS– May 2019

Input: AMSR-E multi-frequency brightness temperatures

Target: SMOS CATDS Level 3 soil moisture Goal: Construct long-time series for climate data records of soil moisture

Reference : Rodriguez-Fernandez et al.

2016, Remote Sensing Data dissemination: CATDS

Near-real-time products

Pure data-driven retrievals Application for data assimilation

Centre d’Etudes Spatiales de la BIOsphère (CESBIO) CNES, CNRS, U. Toulouse, IRD, Toulouse, France

Input: SMOS Near-Real-Time multi-incidence angle brightness temperatures and ECWMF model soil temperature

Target:: SMOS ESA Level 2 soil moisture Goal: To retrieve soil moisture from SMOS observation in near-real time (less than 3.5 hours after sensing)

Reference : Rodriguez-Fernandez et al.

2017, Hydrology and Earth System Sciences Data dissemination: EUMETSAT

EumetCast, ESA SMOS dissemination portal

SMOS

Terra/Aqua

MODIS, AMSR-E Metop

ASCAT

Integrated Forecast System

In Situ

measurements

ECOCLIMAP Sand/clay

Input: SMOS Near-Real-Time multi-incidence angle brightness temperatures

Target: ECMWF H-TESSEL soil moisture in the first soil layer (0-7 cm) Goal: To compute from SMOS observation a soil moisture compatible with ECMWF model simulations for efficient data assimilation

Reference : Rodriguez-Fernandez et al. 2019, preprints.org (submitted to Remote Sensing)

Data assimilation: SMOS neural network soil moisture will be assimilated operationally at ECMWF from cycle 46r1 (June 2019) Input: SMOS Near-Real-Time multi-incidence angle

brightness temperatures, MODIS NDVI, ECWMF model soil temperature

Target: in situ measurements of soil moisture

Goal: To retrieve soil moisture from SMOS observation with a neural network trained on in situ measurements. Retrieval independent of land surface models or radiation transfer computations

Reference : Rodriguez-Fernandez et al. 2017, IGARSS

Input: SMOS Near-Real-Time multi-incidence angle brightness temperatures, MODIS NDVI, ECOCLIMAP sand/clay fraction, ASCAT backscattering

Target: ECMWF H-TESSEL soil moisture in the first soil layer (0-7 cm) Goal: To retrieve soil moisture extracting the synergies from passive (SMOS) and active (ASCAT) microwaves observations

Reference : Rodriguez-Fernandez et al. 2015, IEEE TGARS

Abstract

The Soil Moisture and Ocean Salinity (SMOS) satellite is an interferometric passive radiometer launched by ESA in 2009. After three year acquiring data, in 2012, the ESA Support to Science Element « SMOS + Neural Network » project started to study the use of machine learning techniques, in particular neural networks (NNs), to process SMOS data to estimate soil moisture. Since then, several

applications have been studied and successfully implemented operationally in the framework of different subsequent projects. All of these projects have in common the use of neural networks to exploit the synergies from multi-sources data bases containing data from passive microwave radiometers at different frequencies, active microwave scatterometers, optical/infrared reflectivities, numerical weather

prediction models, in situ measurements and static maps of soil and vegetation properties.

Machine Learning for SMOS

N.J. Rodriguez-Fernandez, P. Richaume, Y.H. Kerr

Neural networks to obtain an added value from a multi-source data base

Long-time series Multi-sensor synergy

Acknowledgements These studies have been supported by the ESA -ECMWF SMOS contract, ESA support To Science Element SMOS+Neural Network, ESA SMOS Soil Moisture Expert Support Laboratory contract , by CNES (Centre National d’Etudes Spatiales) TOSCA program and by the French SMOS ground segment (CATDS).

ESA LPS– May 2019

Input: AMSR-E multi-frequency brightness temperatures

Target: SMOS CATDS Level 3 soil moisture Goal: Construct long-time series for climate data records of soil moisture

Reference : Rodriguez-Fernandez et al.

2016, Remote Sensing Data dissemination: CATDS

Near-real-time products

Pure data-driven retrievals Application for data assimilation

Centre d’Etudes Spatiales de la BIOsphère (CESBIO) CNES, CNRS, U. Toulouse, IRD, Toulouse, France

Input: SMOS Near-Real-Time multi-incidence angle brightness temperatures and ECWMF model soil temperature

Target:: SMOS ESA Level 2 soil moisture Goal: To retrieve soil moisture from SMOS observation in near-real time (less than 3.5 hours after sensing)

Reference : Rodriguez-Fernandez et al.

2017, Hydrology and Earth System Sciences Data dissemination: EUMETSAT

EumetCast, ESA SMOS dissemination portal

SMOS

Terra/Aqua

MODIS, AMSR-E Metop

ASCAT

Integrated Forecast System

In Situ

measurements

ECOCLIMAP Sand/clay

Input: SMOS Near-Real-Time multi-incidence angle brightness temperatures

Target: ECMWF H-TESSEL soil moisture in the first soil layer (0-7 cm) Goal: To compute from SMOS observation a soil moisture compatible with ECMWF model simulations for efficient data assimilation

Reference : Rodriguez-Fernandez et al. 2019, preprints.org (submitted to Remote Sensing)

Data assimilation: SMOS neural network soil moisture will be assimilated operationally at ECMWF from cycle 46r1 (June 2019) Input: SMOS Near-Real-Time multi-incidence angle

brightness temperatures, MODIS NDVI, ECWMF model soil temperature

Target: in situ measurements of soil moisture

Goal: To retrieve soil moisture from SMOS observation with a neural network trained on in situ measurements. Retrieval independent of land surface models or radiation transfer computations

Reference : Rodriguez-Fernandez et al. 2017, IGARSS

Input: SMOS Near-Real-Time multi-incidence angle brightness temperatures, MODIS NDVI, ECOCLIMAP sand/clay fraction, ASCAT backscattering

Target: ECMWF H-TESSEL soil moisture in the first soil layer (0-7 cm) Goal: To retrieve soil moisture extracting the synergies from passive (SMOS) and active (ASCAT) microwaves observations

Reference : Rodriguez-Fernandez et al. 2015, IEEE TGARS

Abstract

The Soil Moisture and Ocean Salinity (SMOS) satellite is an interferometric passive radiometer launched by ESA in 2009. After three year acquiring data, in 2012, the ESA Support to Science Element « SMOS + Neural Network » project started to study the use of machine learning techniques, in particular neural networks (NNs), to process SMOS data to estimate soil moisture. Since then, several

applications have been studied and successfully implemented operationally in the framework of different subsequent projects. All of these projects have in common the use of neural networks to exploit the synergies from multi-sources data bases containing data from passive microwave radiometers at different frequencies, active microwave scatterometers, optical/infrared reflectivities, numerical weather

prediction models, in situ measurements and static maps of soil and vegetation properties.

Machine Learning for SMOS

N.J. Rodriguez-Fernandez, P. Richaume, Y.H. Kerr

Neural networks to obtain an added value from a multi-source data base

Long-time series Multi-sensor synergy

Acknowledgements These studies have been supported by the ESA -ECMWF SMOS contract, ESA support To Science Element SMOS+Neural Network, ESA SMOS Soil Moisture Expert Support Laboratory contract , by CNES (Centre National d’Etudes Spatiales) TOSCA program and by the French SMOS ground segment (CATDS).

ESA LPS– May 2019

Input: AMSR-E multi-frequency brightness temperatures

Target: SMOS CATDS Level 3 soil moisture Goal: Construct long-time series for climate data records of soil moisture

Reference : Rodriguez-Fernandez et al.

2016, Remote Sensing

Data dissemination: CATDS

Near-real-time products

Pure data-driven retrievals Application for data assimilation

Centre d’Etudes Spatiales de la BIOsphère (CESBIO) CNES, CNRS, U. Toulouse, IRD, Toulouse, France

Input: SMOS Near-Real-Time multi-incidence angle brightness temperatures and ECWMF model soil temperature

Target:: SMOS ESA Level 2 soil moisture Goal: To retrieve soil moisture from SMOS observation in near-real time (less than 3.5 hours after sensing)

Reference : Rodriguez-Fernandez et al.

2017, Hydrology and Earth System Sciences Data dissemination: EUMETSAT

EumetCast, ESA SMOS dissemination portal

SMOS

Terra/Aqua

MODIS, AMSR-E Metop

ASCAT

Integrated Forecast System

In Situ

measurements

ECOCLIMAP Sand/clay

Input: SMOS Near-Real-Time multi-incidence angle brightness temperatures

Target: ECMWF H-TESSEL soil moisture in the first soil layer (0-7 cm) Goal: To compute from SMOS observation a soil moisture compatible with ECMWF model simulations for efficient data assimilation

Reference : Rodriguez-Fernandez et al. 2019, preprints.org (submitted to Remote Sensing)

Data assimilation: SMOS neural network soil moisture will be

assimilated operationally at ECMWF from cycle 46r1 (June 2019) Input: SMOS Near-Real-Time multi-incidence angle

brightness temperatures, MODIS NDVI, ECWMF model soil temperature

Target: in situ measurements of soil moisture

Goal: To retrieve soil moisture from SMOS observation with a neural network trained on in situ measurements. Retrieval independent of land surface models or radiation transfer computations

Reference : Rodriguez-Fernandez et al. 2017, IGARSS

Input: SMOS Near-Real-Time multi-incidence angle brightness

temperatures, MODIS NDVI, ECOCLIMAP sand/clay fraction, ASCAT backscattering

Target: ECMWF H-TESSEL soil moisture in the first soil layer (0-7 cm) Goal: To retrieve soil moisture extracting the synergies from passive (SMOS) and active (ASCAT) microwaves observations

Reference : Rodriguez-Fernandez et al. 2015, IEEE TGARS

Abstract

The Soil Moisture and Ocean Salinity (SMOS) satellite is an interferometric passive radiometer launched by ESA in 2009. After three year acquiring data, in 2012, the ESA Support to Science Element « SMOS + Neural Network » project started to study the use of machine learning techniques, in particular neural networks (NNs), to process SMOS data to estimate soil moisture. Since then, several

applications have been studied and successfully implemented operationally in the framework of different subsequent projects. All of these projects have in common the use of neural networks to exploit the synergies from multi-sources data bases containing data from passive microwave radiometers at different frequencies, active microwave scatterometers, optical/infrared reflectivities, numerical weather

prediction models, in situ measurements and static maps of soil and vegetation properties.

Machine Learning for SMOS

N.J. Rodriguez-Fernandez, P. Richaume, Y.H. Kerr

Neural networks to obtain an added value from a multi-source data base

Long-time series Multi-sensor synergy

Acknowledgements These studies have been supported by the ESA -ECMWF SMOS contract, ESA support To Science Element SMOS+Neural Network, ESA SMOS Soil Moisture Expert Support Laboratory contract , by CNES (Centre National d’Etudes Spatiales) TOSCA program and by the French SMOS ground segment (CATDS).

ESA LPS– May 2019

Input: AMSR-E multi-frequency brightness temperatures

Target: SMOS CATDS Level 3 soil moisture Goal: Construct long-time series for climate data records of soil moisture

Reference : Rodriguez-Fernandez et al.

2016, Remote Sensing

Data dissemination: CATDS

Near-real-time products

Pure data-driven retrievals Application for data assimilation

Centre d’Etudes Spatiales de la BIOsphère (CESBIO)

CNES, CNRS, U. Toulouse, IRD, Toulouse, France

Input: SMOS Near-Real-Time multi-incidence angle brightness temperatures and ECWMF model soil temperature

Target:: SMOS ESA Level 2 soil moisture Goal: To retrieve soil moisture from SMOS observation in near-real time (less than 3.5 hours after sensing)

Reference : Rodriguez-Fernandez et al.

2017, Hydrology and Earth System Sciences Data dissemination: EUMETSAT

EumetCast, ESA SMOS dissemination portal

SMOS

Terra/Aqua

MODIS, AMSR-E Metop

ASCAT

Integrated Forecast System

In Situ

measurements

ECOCLIMAP Sand/clay

Input: SMOS Near-Real-Time multi-incidence angle brightness temperatures

Target: ECMWF H-TESSEL soil moisture in the first soil layer (0-7 cm) Goal: To compute from SMOS observation a soil moisture compatible with ECMWF model simulations for efficient data assimilation

Reference : Rodriguez-Fernandez et al. 2019, Remote Sensing) Data assimilation: SMOS neural network soil moisture will be

assimilated operationally at ECMWF from cycle 46r1 (11 June 2019) Input: SMOS Near-Real-Time multi-incidence angle

brightness temperatures, MODIS NDVI, ECWMF model soil temperature

Target: in situ measurements of soil moisture

Goal: To retrieve soil moisture from SMOS observation with a neural network trained on in situ measurements. Retrieval independent of land surface models or radiation transfer computations

Reference : Rodriguez-Fernandez et al. 2017, IGARSS

Input: SMOS Near-Real-Time multi-incidence angle brightness

temperatures, MODIS NDVI, ECOCLIMAP sand/clay fraction, ASCAT backscattering

Target: ECMWF H-TESSEL soil moisture in the first soil layer (0-7 cm) Goal: To retrieve soil moisture extracting the synergies from passive (SMOS) and active (ASCAT) microwaves observations

Reference : Rodriguez-Fernandez et al. 2015, IEEE TGARS

Abstract

The Soil Moisture and Ocean Salinity (SMOS) satellite is an interferometric passive radiometer launched by ESA in 2009. After three year acquiring data, in 2012, the ESA Support to Science Element « SMOS + Neural Network » project started to study the use of machine learning techniques, in particular neural networks (NNs), to process SMOS data to estimate soil moisture. Since then, several

applications have been studied and successfully implemented operationally in the framework of different subsequent projects. All of these projects have in common the use of neural networks to exploit the synergies from multi-sources data bases containing data from passive microwave radiometers at different frequencies, active microwave scatterometers, optical/infrared reflectivities, numerical weather

prediction models, in situ measurements and static maps of soil and vegetation properties.

RT models

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Application: near real time products

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Problématique: Les centres opérationnels de météorologie ont besoin de l’humidité du sol en temps quasi-réel (moins de trois heures)

Solution proposée: Modèle inverse par réseaux de neurones

Produit officiel distribué par

Projet SMOS Near Real-Time

Algorithme statistique: 100 fois plus rapide que l’algorithme physique !

Temperature Sol (Modèle ECMWF)

Humidité du sol

Rodriguez-Fernandez et al. (2017, Hydrology and Earth System Sciences)

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Satellite Soil Moisture Validation and Application Workshop Wien September 19-20 2017-- YHKerr

Slightly better performances than the original L2 SM data

Much faster ! Available in near real time for operational applications

Implemented by : With support by :

Delivered to :

Disseminated by:

Near Real Time SM

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Extreme events: floods

SMOS Near Real Time soil moisture

2019 Floods in Australia

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Application : data assimilation

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Rodriguez-Fernandez et al.

(2019, Remote Sensing)

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Application : data assimilation

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Projet SMOS Data Assimilation

Rodriguez-Fernandez et al.

(2019, Remote Sensing)

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SMOS NN SM data assimilation in meteorological models

T air 850 hPa, forecast 36 hours, July-September SMOS NN SM improves the forecast

Blue: positive impact

Red: negative impact

▪ SMOS soil moisture obtained with neural networks trained on ECMWF models

▪ Surface-only DA system forced by ERA-Interim reanalysis

▪ Atmospheric forecast using the analyzed surface fields

Rodriguez-Fernandez, de Rosnay, Albergel et al. (2019, Remote Sensing)

Assimilation of SMOS NN SM,

Tair 2m, RH 2m Assimilation of

Tair 2m, RH 2m

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Atmospheric forecasts: T 2m

Version May 22, 2019 submitted to Remote Sens. 19 of 23

Figure 9. Upper panel: difference of the Pearson correlation of NNSM experiment time series with respect to in situ measurements and the Pearson correlation of OL experiment time series with respect to in situ measurements. Lower panel: difference of the RMS of NNSM experiment time series with respect to in situ measurements and RMS of OL experiment time series with respect to in situ measurements. In both cases, blue points show that the analysed time series are closer to the in situ measurement (higher correlation and lower RMS).

Figure 10. Evaluation of the atmospheric forecast skill. The plots show the RMSE of the T 2m forecast

for the assimilation experiments minus the RMSE for the OL experiment as a function of the forecast

day in two periods : April-June (upper panels) and July-September (lower panels). The results are shown

for three latitude ranges: [-90 , -20 ] (left panels), [-20 , 20 ] (middle panels), [20 , 90 ] (right panels).

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5

th

SSMVA GMU Fairfax October 24-25 2018 – Yann H. KERR

Operational data assimilation

• SMOS Neural Network SM operationally assimilated at

ECMWF since 11 June 2019

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Application: multi-sensor synergy

• Texte niveau 1

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Problématique: Les capteurs passifs SMOS et actifs ASCAT peuvent être complémentaires mais il n’y pas de modèles physiques passif à1.4 GHz et actif à 5 GHz

Solution proposée: Modèle inverse par réseaux de neurones pour utiliser la synergie des deux capteurs

Projet

L’utilisation simultanée des deux capteurs capture mieux la

dynamique de l’humidité du sol

Rodriguez-Fernandez et al 2015 (IEEE Trans. Geoscience and Remote Sensing)

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Application: climate data records

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Projet Fusion AMSR-E/SMOS Climate Change Initiative

Rodriguez-Fernandez et al 2016 (Remote Sensing)

Problématique: L’humidité du sol est une variable climatique essentielle … mais les satellites ont une durée de vie limitée

Solution proposée: Créer des series temporelles longues en utilisant plusieurs satellites et des réseaux de neurones

Produit distribué par le

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Longues series temporelles et teleconnections

NN CCI

B. Cluzet

Master Thesis

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ULID and SMOS-HR

SMOS-HR

• Interferometric L-band radiometer

• Full polarization

• Multi-angular capabilities

• 10 km spatial resolution

• Phase 0 study at CNES

(CESBIO, Airbus Defence and Space)

ULID

Unconnected L-band Interferometer Demonstrator

3 nano-satellites

Phase A study at CNES

Deep learning for image reconstruction (visibilities inversion)

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Summary

Classical multilayer perceptrons are useful for many

scientific and operational applications in particular dealing with radiometry and not image processing

They can help to extract an added value from multi-source/

hybrid data bases … and they are simple

We are currently using similar techniques to retrieve

vegetation parameters such as biomass or for downscaling coarse resolution soil moisture estimations

@SMOS_satellite, @NemesioRF

nemesio.rodriguez@cesbio.cnes.fr

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A pure data-driven algorithm

Using in situ measurements for the training from the

International Soil Moisture Network : SCAN, SNOTEL, USCRN

Rodríguez-Fernández et al (2017, IGARSS)

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NAO-anomalies de SM

NAO +

NAO +

NN CCI

NAO -

NAO -

Anomalies de SM pour NN et CCI pendant des mois NAO + (a-b) et NAO- (c- d)

c)

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N. Rodríguez Fernández. Rencontres R&D Meteo France, 18 Juin 2019

Remote sensing observations

Advanced Microwave Scanning Radiometer- EOS (AMSR-E)

• Two polarizations, Single incidence angle

• 6 Bands (6.9 GHz, 18 GHz, 23.8 GHz, 36.5 GHz, 89.0 GHz)

• Resolution: 56 km @ 6.9 GHz

Soil Moisture and Ocean Salinity (SMOS)

• Synthetic aperture (equivalent to a 7 m dish). Resolution ~ 43 km

• Full polarization, Multi-angular (0-60º), L-Band (1.4 GHz)

ASCAT

Advanced scatterometer (ASCAT)

• Active, C-band (5GHz) resolution ~ 50 km MODIS

• visible and infrared bands, resolution 250 m – 1km

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N. Rodríguez Fernández. Rencontres R&D Meteo France, 18 Juin 2019

Models and in situ measurements

ECMWF land surface model H-TESSEL (Balsamo et al. 2009)

SMOS Level 3 soil moisture (and opacity) Al Bitar et al. (2017, ESSD)

Radiation transfer computations using L-MEB (Wigneron et al. 2007)

In situ measurements compiled by the

ISMN (Dorigo et al. 2011, HESS)

Références

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