Spatial and temporal variability of biophysical variables in southwestern France from airborne L-band radiometry

Hydrology and Earth System Sciences

Volumn 16, Issue 6, 2012, Pages 1725-1743

  Zakharova, E ^a   Calvet, J C ^a   Lafont, S ^a   Albergel, C ^a,e   Wigneron, J P ^b   Parde M ^c   Kerr Y , ^d   Zribi, M ^d  

^a CENTRE NATIONAL DE RECHERCHES MÉTÉOROLOGIQUES   (France)

^b BORDEAUX SCIENCES AGRO   (France)

^c CNRS   (France)

^d CNES   (France)

^e EUROPEAN CENTRE FOR MEDIUM RANGE WEATHER FORECASTS   (United Kingdom)

Author keywords

[No Author keywords available]

Indexed keywords

AIRBORNE RADIOMETERS; AUTOMATIC NETWORKS; BIO-PHYSICAL VARIABLES; BRIGHTNESS TEMPERATURE MEASUREMENT; CALIBRATION AND VALIDATIONS; DATA SETS; FLIGHT LINES; GRID CELLS; IN-SITU OBSERVATIONS; INTEGRATED APPLICATIONS; L-BAND RADIOMETRY; LEAF AREA INDEX; MICROWAVE EMISSIONS; SATELLITE MISSION; SOIL MOISTURE AND OCEAN SALINITY (SMOS); SPATIAL AND TEMPORAL VARIABILITY; SPATIAL CORRELATIONS; SPATIAL RESOLUTION; SPATIAL VARIABILITY; STANDARD DEVIATION; SUB-GRIDS; SURFACE SOIL MOISTURE; TEMPORAL CHANGE; TEMPORAL CORRELATIONS; VEGETATION COVER; VEGETATION OPTICAL DEPTH; VEGETATION TYPE; VEGETATION WATER CONTENT; WATERBODIES;

BIOSPHERICS; CELLS; COMPUTER SIMULATION; CYTOLOGY; GEOLOGIC MODELS; SOIL MOISTURE; STATISTICS; TEMPERATURE MEASUREMENT; VIDEO ON DEMAND;

VEGETATION;

AIRBORNE SENSING; BRIGHTNESS TEMPERATURE; CORRELATION; LEAF AREA INDEX; MICROWAVE RADIOMETER; OPTICAL DEPTH; SMOS; SPATIAL DISTRIBUTION; SPATIAL RESOLUTION; SPATIOTEMPORAL ANALYSIS; VEGETATION COVER; VEGETATION TYPE; WATER CONTENT;

FRANCE;

EID: 84863214831     PISSN: 10275606     EISSN: 16077938     Source Type: Journal    
DOI: 10.5194/hess-16-1725-2012     Document Type: Article

References (76)

1. Albergel, C., Rüdiger, C., Pellarin, T., Calvet, J.-C., Fritz, N., Froissard, F., Suquia, D., Petitpa, A., Piguet, B., and Martin, E. From near-surface to root-zone soil moisture using an exponential filter an assessment of the method based on in-situ observations and model simulations, Hydrol. Earth Syst. Sci., 12, 1323-1337, doi10.5194/hess-12-1323-2008, 2008.
2. Albergel, C., Rüdiger, C., Carrer, D., Calvet, J.-C., Fritz, N., Naeimi, V., Bartalis, Z., and Hasenauer, S. An evaluation of ASCAT surface soil moisture products with in-situ observations in Southwestern France, Hydrol. Earth Syst. Sci., 13, 115-124, doi10.5194/hess-13-115-2009, 2009.
3. Albergel, C., Calvet, J.-C., de Rosnay, P., Balsamo, G., Wagner, W., Hasenauer, S., Naeimi, V., Martin, E., Bazile, E., Bouyssel, F., and Mahfouf, J.-F. Cross-evaluation of modelled and remotely sensed surface soil moisture with in situ data in southwestern France, Hydrol. Earth Syst. Sci., 14, 2177-2191, doi10.5194/hess-14-2177-2010, 2010.
4. Albergel, C., Zakharova, E., Calvet, J.-C., Zribi, M., Pardé, M., Wigneron, J.-P., Novello, N., Kerr, Y., Mialon, A., and Fritz, N. A first assessment of the SMOS data in Southwestern France using in situ and airborne soil moisture estimates the CAROLS airborne campaign, Remote Sens. Environ., 115, 2718-2728, doi10.1016/j.rse.2011.06.012, 2011.
5. Baret, F., Makhmara, H., Lacaze, R., and Smets, B. Biopar Product User Manual LAI, FAPAR, Fcover NDVI Version 1 from SPOT/VEGETATION data, GEOLAND2 FP7 project, available at http//web.vgt.vito.be/documents/BioPar/, last access May 2012.
6. Bircher, S., Balling, J. E., Skou, N., and Kerr, Y. Validation of SMOS brightness temperatures during the HOBE airborne campaign,Western Denmark, IEEE T. Geosci. Remote, 50, 1468-1482, doi10.1109/TGRS.2011.2170177, 2012.
7. Brut, A., Rüdiger, C., Lafont, S., Roujean, J.-L., Calvet, J.-C., Jarlan, L., Gibelin, A.-L., Albergel, C., Le Moigne, P., Soussana, J.-F., Klumpp, K., Guyon, D., Wigneron, J.-P., and Ceschia, E. Modelling LAI at a regional scale with ISBA-A-gs comparison with satellite-derived LAI over southwestern France, Biogeosciences, 6, 1389-1404, doi10.5194/bg-6-1389-2009, 2009.
8. Calvet, J.-C. Investigating soil and atmospheric plant water stress using physiological and micrometeorological data, Agr. Forest Meteorol., 103, 229-247, 2000. (Pubitemid 30343519)
9. 2-enrichment effects using an interactive vegetation SVAT scheme, Agr. Forest Meteorol., 108, 129-152, 2001. (Pubitemid 32453795)
10. Calvet, J.-C., Noilhan, J., Roujean, J.-L., Bessemoulin, P., Cabelguenne, M., Olioso, A., and Wigneron, J.-P. An interactive vegetation SVAT model tested against data from six contrasting sites, Agr. Forest Meteorol., 92, 73-95, 1998. (Pubitemid 28422196)
11. Calvet, J.-C., Rivalland, V., Picon-Cochard, C., and Guehl, J.- M. Modelling forest transpiration and CO2 fluxes - response to soil moisture stress, Agr. Forest Meteorol., 124, 143-156, doi10.1016/j.agrformet.2004.01.007, 2004. (Pubitemid 38946011)
12. Calvet, J.-C., Fritz, N., Froissard, F., Suquia, D., Petitpa, A., and Piguet, B. In-situ soil moisture observations for the CAL/VAL of SMOS the SMOSMANIA network, International Geoscience and Remote Sensing Symposium, IGARSS, Barcelona, Spain, 1196-1199, doi10.1109/IGARSS.2007.4423019, 23- 28 July 2007.
13. Calvet, J.-C., Wigneron, J.-P., Walker, J., Karbou, F., Chanzy, A., and Albergel, C. Sensitivity of passive microwave observations to soil moisture and vegetation water content Lband to W-band, IEEE T. Geosci. Remote, 49, 1190-1199, doi10.1109/TGRS.2010.2050488, 2011.
14. Cano, A., Saleh, K.,Wigneron, J. P., Antol'?n, C., Ballinge, J., Kerr, Y., Kruszewski, A., Millan-Scheiding, C., Søbjærge, S., Skoue, N., and L'opez-Baeza, E. The SMOS Mediterranean Ecosystem L-Band characterisation EXperiment (MELBEX-I) over natural shrubs, Remote Sens. Environ., 114, 844-853, 2010.
15. Chanzy, A., Schmugge, T. J., Calvet, J.-C., Kerr, Y., van Oevelen, P., Grosjean, O., and Wang, J. R. Airborne microwave radiometry on a semi-arid area during HAPEX-Sahel, J. Hydrol., 188-189, 285-309, 1997.
16. De Rosnay, P., Calvet, J.-C., Kerr, Y., Wigneron, J. P., Lematre, F., Escorihuela, M. J., Munoz Sabater, J., Saleh, K., Barrie, J., Coret, L., Cherel, G., Dedieu, G., Durbe, R., Fritz, N., Froissard, F., Kruszewski, A., Lavenu, F., Suquia, D., and Waldteufel, P. SMOSREX A long term field campaign experiment for soil moisture and land surface processes remote sensing, Remote Sens. Environ., 102, 377-389, 2006. (Pubitemid 44218813)
17. De Rosnay, P., Gruhier, C., Timouk, F., Baup, F., Mougin, E., Hiernaux, P., Kergoat, L., and LeDantec, V. Multi-scale soil moisture measurements at the Gourma meso-scale site in Mali, J. Hydrol., 375, 241-252, 2009.
18. Dobson, M. C., Ulaby, F. T., Hallikainen, M. T., and El-Rayes, M. A. Microwave dielectric behaviour of wet soil - Part II dielectric mixing models, IEEE T. Geosci. Remote, GE-23, 35-46, 1985.
19. Draper, C. S.,Walker, J. P., Steinle, P. J., de Jeu, R., and Holmes, T. An evaluation of AMSR-E derived soil moisture over Australia, Remote Sens. Environ., 113, 703-710, 2007.
20. Drusch, M., Wood, E. F., Gao, H., and Thiele, A. Soil moisture retrieval during the Southern Great Plains Hydrologic Experiment 1999 A comparison between experimental remote sensing data and operational products, Water Resour. Res., 40, W02504, doi10.1029/2003WR002441, 2004.
21. Durand, Y., Brun, E., Merindol, L., Guyomarch, G., Lesaffre, B., and Martin, E. A meteorological estimation of relevant parameters for snow models, Ann. Glaciol., 18, 65-71, 1993.
22. Faroux, S., Roujean, J.-L., Kaptué, A., and Masson, V. La base de données de paramètres de surface ECOCLIMAP-II sur l'Europe, Note de centre du Groupe de Météorologie a Moyenne Echelle, 86, Météo-France, CNRM, Toulouse, France, 120 pp., 2009.
23. Grant, J. P., Saleh-Contell, K., Wigneron, J. P., Guglielmetti, M., Kerr, Y., Schwank, M., Skou, N., and Van de Griend, A. A. Calibration of the L-MEB model over a coniferous and a deciduous forest, IEEE T. Geosci. Remote, 46, 808-818, 2008. (Pubitemid 351324775)
24. Gruhier, C., de Rosnay, P., Hasenauer, S., Holmes, T., de Jeu, R., Kerr, Y., Mougin, E., Njoku, E., Timouk, F., Wagner, W., and Zribi, M. Soil moisture active and passive microwave products intercomparison and evaluation over a Sahelian site, Hydrol. Earth Syst. Sci., 14, 141-156, doi10.5194/hess-14-141- 2010, 2010.
25. Guglielmetti, M., Schwank, M., Mätzler, C., Oberdörster, C., Vanderborght, J., and Flühler, H. FOSMEX Forest soil moisture experiments with microwave radiometry, IEEE T. Geosci. Remote, 46, 727-735, doi10.1109/TGRS.2007.914797, 2008. (Pubitemid 351324768)
26. Jackson, T., Hawley, M. E., Shuie, J., O'Neill, P. E., Owe, M., Delnore, S. V., and Lawrence, R. W. Assessment of preplanting soil moisture using airborne microwave sensors, Hydrologic Applications of Space Technology, Proceedings of the Cocoa Beach Workshop, Florida, August 1985, IAHS Publ., 160, 111-118, 1986.
27. Jackson, T. J. and Schmugge, T. J. Vegetation effects on the microwave emission of soils, Remote Sens. Environ., 36, 203-212, 1991.
28. Jain, A. K., Murty, M. N., and Flynn, P. J. Data clustering a review, ACM Comput. Surv., 31, 264-323, 1999.
29. Jones, O., Jones, L., Kimball, J., and McDonald, K. Satellite passive microwave remote sensing for monitoring global land surface phenology, Remote Sens. Environ., 115, 1102-1114, 2011.
30. Kerr, Y. H. and Wigneron, J.-P. Vegetation models and observations, a review, in Passive Microwave Remote Sensing of Land- Atmosphere Interactions, edited by Choudhury, B. J., Kerr, Y. H., Njoku, E. G., and Pampaloni, P., VSP, Utrecht, The Netherlands, 317-344, 1995.
31. Kerr, Y., Waldteufel, P., Wigneron, J.-P., Martinuzzi, J.-M., Font, J., and Berger, M. Soil moisture retrieval from space the soil moisture and ocean salinity (SMOS) mission, IEEE T. Geosci. Remote, 39, 1729-1736, 2001.
32. Kirdyashev, K. P., Chukhlantsev, A. A., and Shutko, A. M. Microwave radiation of the Earth's surface in the presence of vegetation cover, Radio Eng. Electron. Phys., 24, 256-264, 1979.
33. Kochendorfer, J. P. and Ram?rez, J. A. Modeling the monthly mean soil-water balance with a statistical-dynamical ecohydrology model as coupled to a two-component canopy model, Hydrol. Earth Syst. Sci., 14, 2099-2120, doi10.5194/hess-14-2099- 2010, 2010.
34. Lee, K., Burke, Eleanor J., Shuttleworth, W., and Harlow, R. Influence of vegetation on SMOS mission retrievals, Hydrol. Earth Syst. Sci., 6, 153-166, doi10.5194/hess-6-153-2002, 2002. (Pubitemid 34735925)
35. Liu, Y., De Jeu, R. A. M., Van Dijk, A. I. J. M., and Owe, M. TRMM-TMI satellite observed soil moisture and vegetation density (1998-2005) show strong connection with El Nino in eastern Australia, Geophys. Res. Lett., 34, L15401, doi10.1029/2007GL030311, 2007. (Pubitemid 47521280)
36. Liu, Y., De Jeu, R. A. M., McCabe, M. F., Evans, J. P., and Van Dijk, A. I. J. M. Global long-term passive microwave satellite based retrievals of vegetation optical depth, Geophys. Res. Lett., 38, L18402, doi10.1029/ 2011GL048684, 2011.
37. Masson, V., Champeaux, J.-L., Chauvin, F., Meriguet, C., and Lacaze, R. A global database of land surface parameters at 1-km resolution in meteorological and climate models, J. Climate, 16, 1261-1282, 2003. (Pubitemid 36751513)
38. Miralles, D. G., Holmes, T. R. H., De Jeu, R. A. M., Gash, J. H., Meesters, A. G. C. A., and Dolman, A. J. Global land-surface evaporation estimated from satellite-based observations, Hydrol. Earth Syst. Sci., 15, 453-469, doi10.5194/hess-15-453-2011, 2011.
39. Mohr, K. I., Famiglietti, J. S., Boone, A., and Starks, P. J. Modeling soil moisture and surface flux variability with an untuned landsurface scheme A case study from the Southern Great Plains 1997 Hydrology Experiment, J. Hydrometeorol., 1, 154-169, 2000.
40. Njoku, E. G. and Chan, S. K. Vegetation and surface roughness effects on AMSR-E land observations, Remote Sens. Environ., 100, 190-199, 2006. (Pubitemid 43083568)
41. Njoku, E. G. and Kong, J.-A. Theory for passive microwave remote sensing of near-surface soil moisture, J. Geophys. Res., 82, 3108-3118, doi10.1029/jb082i020p03108, 1977.
42. Noilhan, J. and Lacarrère, P. GCM gridscale evaporation from mesoscale modelling, J. Climate, 8, 206-223, 1995.
43. Panceira, R., Walker, J. P., Kalma, J. D., Kim, E. J., Hacker, J. M., Merlin, O., Berger, M., and Skou, N. The NAFE'05/CoSMOSdata set toward SMOS soil moisture retrieval, downscaling and assimilation, IEEE T. Geosci. Remote, 46, 736-746, 2008.
44. Panciera, R., Walker, J. P., Kalma, J. D., Kim, E. J., Saleh, K., and Wigneron, J.-P. Evaluation of the SMOS L-MEB passive microwave soil moisture retrieval algorithm, Remote Sens. Environ., 113, 435-444, 2009.
45. Pardé, M., Zribi, M., Fanise, P., and Dechambre, M. Analysis of RFI issue using the CAROLS L-Band experiment, IEEE T. Geosci. Remote, 49, 1063-1070, 2011a.
46. Pardé, M., Zribi, M., Wigneron, J. P., Dechambre, M., Fanise, P., Kerr, Y., Crapeau, M., Saleh, K., Calvet, J.-C., Albergel, C., Mialon, A., and Novello, N. Soil moisture estimations based on airborne CAROLS L-band microwave data, Remote Sens., 3, 2591-2604, doi10.3390/rs3122591, 2011b.
47. Parrens, M., Zakharova, E., Lafont, S., Calvet, J.-C., Kerr, Y., Wagner, W., and Wigneron, J.-P. Comparing soil moisture retrievals from SMOS and ASCAT over France, Hydrol. Earth Syst. Sci., 16, 423-440, doi10.5194/hess-16-423-2012, 2012.
48. Pellarin, T., Wigneron, J. P., Calvet, J.-C., and Waldteufel, P. Global soil moisture retrieval from a synthetic L-band brightness temperature data set, J. Geophys. Res., 108, 4364, doi10.1029/2002JD003086, 2003a.
49. Pellarin, T.,Wigneron, J.-P., Calvet, J.-C., Berger, M., Douville, H., Ferrazzoli, P., Kerr, Y. H., Lopez-Baeza, E., Pulliainen, J., Simmonds, L. P., and Waldteufel, P. Two-year global simulation of L-band brightness temperatures over land, IEEE T. Geosci. Remote, 41, 2135-2139, 2003b.
50. Pellarin, T., Calvet, J.-C., and Wagner, W. Evaluation of ERS scatterometer soil moisture products over a half-degree region in Southwestern France, Geophys. Res. Lett., 33, L17401, doi10.1029/2006GL027231, 2006. (Pubitemid 44945637)
51. Porporato, A. and Rodriguez-Iturbe, I. Ecohydrology - a challenging multidisciplinary research perspective, Hydrolog. Sci. J., 47, 811-821, 2002.
52. Quintana-Segui, P., Le Moigne, P., Durand, Y., Martin, E., Habets, F., Baillon, M., Canellas, C., Franchistéguy, L., and Morel, S. Analysis of near surface atmospheric variables validation of the SAFRAN analysis over France, J. Appl. Meteorol. Clim., 47, 92-107, 2008. (Pubitemid 351351468)
53. Rüdiger, C., Calvet, J.-C., Gruhier, C., Holmes, T., De Jeu, R., and Wagner, W. An intercomparison of ERS-Scat and AMSR-E soil moisture observations with model simulations over France, J. Hydrometeorol., 10, 431-447, doi10.1175/2008JHM997.1, 2009.
54. Saleh, K., Wigneron, J. P., Calvet, J.-C., Lopez-Baeza, E., Ferrazzoli, P., Berger, M., Wursteisen, P., Simmonds, L., and Miller, J. The EuroSTARRS airborne campaign in support of the SMOS mission first results over land surfaces, Int. J. Remote Sens., 25, 177-194, 2004. (Pubitemid 38211477)
55. Saleh, K., Wigneron, J.-P., de Rosnay, P., Calvet, J.-C., and Kerr, Y. Semi-empirical regressions at L-band applied to surface soil moisture retrieval over grass, Remote Sens. Environ., 101, 415-426, 2006a.
56. Saleh, K., Wigneron, J.-P., de Rosnay, P., Calvet, J.-C., Kerr, Y., Waldteufel, P., and Escorihuela, M. J. Impact of rain interception by vegetation and mulch on the L-band emission of natural grass, Remote Sens. Environ., 101, 127-139, 2006b. (Pubitemid 43290240)
57. Saleh, K., Wigneron, J.-P., Waldteufel, P., de Rosnay, P., Schwank, M., Calvet, J.-C., and Kerr, Y. H. Estimates of surface soil moisture under grass covers using L-band radiometry, Remote Sens. Environ., 109, 42-53, 2007. (Pubitemid 46776738)
58. Saleh, K., Kerr, Y. H., Richaume, P., Escorihuela, M. J., Panciera, R., Delwart, S., Boulet, G., Maisongrande, P., Walker, J. P., Wursteisen, P., and Wigneron, J. P. Soil moisture retrievals at Lband using a two-step inversion approach (COSMOS/NAFE'05 Experiment), Remote Sens. Environ., 113, 1304-1312, 2009.
59. Schmugge, T. J. and Jackson, T. J. A dielectric model of the vegetation effects on the microwave emission from soils, IEEE T. Geosci. Remote, 30, 757-760, doi10.1109/36.158870, 1992. (Pubitemid 23579829)
60. Schmugge, T., Jackson, T. J., Kustas, W. P., and Wang, J. R. Passive microwave remote sensing of soil moisture results from HAPEX, FIFE and MONSOON 90, J. Photogram. Remote Sens., 47, 127-143, 1992.
61. Su, Z., Timmermans, W. J., van der Tol, C., Dost, R., Bianchi, R., Gómez, J. A., House, A., Hajnsek, I., Menenti, M., Magliulo, V., Esposito, M., Haarbrink, R., Bosveld, F., Rothe, R., Baltink, H. K., Vekerdy, Z., Sobrino, J. A., Timmermans, J., van Laake, P., Salama, S., van der Kwast, H., Claassen, E., Stolk, A., Jia, L., Moors, E., Hartogensis, O., and Gillespie, A. EAGLE 2006 - Multi-purpose, multi-angle and multi-sensor in-situ and airborne campaigns over grassland and forest, Hydrol. Earth Syst. Sci., 13, 833-845, doi10.5194/hess-13-833-2009, 2009.
62. Wagner,W., Lemoine, G., and Rott, H.: A method of estimating soil moisture from ERS scatterometer and soil data, Remote Sens. Environ., 70, 191-207, 1999a.
63. Wagner, W., Noll, J., Borgeaud, M., and Rott, H. Monitoring soil moisture over the Canadian prairies with the ERS scatterometer, IEEE T. Geosci. Remote, 37, 206-216, 1999b.
64. Wagner, W., Blöschl, G., Pampaloni, P., Calvet, J.-C., Bizzarri, B., Wigneron, J.-P., and Kerr, Y. Operational readiness of microwave remote sensing of soil moisture for hydrologic applications, Nord. Hydrol., 38, 1-20, 2007. (Pubitemid 46210865)
65. Walker, J. P. and Houser, P. R. Requirements of global near surface soil moisture satellite mission accuracy, repeat time and spatial resolution, Adv. Water Resour., 27, 785-801, 2004. (Pubitemid 39122660)
66. Wang, J. R. and Choudhury, B. J. Remote sensing of soil moisture content over bare field at 1.4 GHz frequency, J. Geophys. Res., 86, 5277-5282, 1981.
67. Wang, L., D'Odorico, P., Evans, J. P., Eldridge, D., McCabe, M. F., Caylor, K. K., and King, E. G. Dryland ecohydrology and climate change critical issues and technical advances, Hydrol. Earth Syst. Sci. Discuss., 9, 4777-4825, doi10.5194/hessd-9- 4777-2012, 2012.
68. Wigneron, J.-P., Chanzy, A., Calvet, J.-C., and Bruguier, N. A simple algorithm to retrieve soil moisture and vegetation biomass using passive microwave measurements over crop fields, Remote Sens. Environ., 5, 331-341, 1995.
69. Wigneron, J.-P., Calvet, J.-C., and Kerr, Y. Monitoring water interception by crop fields from passive microwave observations, Agr. Forest Meteorol., 80, 177-194, 1996.
70. Wigneron, J.-P., Waldteufel, P., Chanzy, A., Calvet, J.-C., and Kerr, Y. Two-Dimensional Microwave Interferometer Retrieval Capabilities over Land Surfaces (SMOS Mission), Remote Sens. Environ., 73, 270-282, 2000.
71. Wigneron, J.-P., Chanzy, A., Calvet, J.-C., Olioso, A., and Kerr, Y. Modeling approaches to assimilating L band passive microwave observations over land surfaces, J. Geophys. Res., 107, 4219, doi10.1029/2001JD000958, 2002. (Pubitemid 43197298)
72. Wigneron, J.-P., Kerr, Y.,Waldteufel, P., Saleh, K., Escorihuela, M.- J., Richaume, P., Ferrazzoli, P., de Rosnay, P., Gurney, R., Calvet, J.-C., Grant, J. P., Guglielmetti, M., Hornbuckle, B.,Mätzler, C., Pellarin, T., and Schwankh, M. L-band microwave emission of the biosphere (L-MEB) model description and calibration against experimental data sets over crop fields, Remote Sens. Environ., 107, 639-655, 2007. (Pubitemid 46517628)
73. Wigneron, J.-P., Chanzy, A., de Rosnay, P., Rüdiger, C., and Calvet, J.-C. Estimating the effective soil temperature at L-band as a function of soil properties, IEEE T. Geosci. Remote, 46, 797-801, 2008.
74. Yang, L., Wei, W., Chen, L., Jia, F., and Mo, B. Spatial variation of shallow and deep soil moisture in the semi-arid loess hilly area, China, Hydrol. Earth Syst. Sci. Discuss., 9, 4553-4586, doi10.5194/hessd-9-4553-2012, 2012.
75. Zhao, D., Kuenzer, C., Fu, C., and Wagner, W. Evaluation of the ERS scatterometer-derived soil water index to monitor water availability and precipitation distribution at three different scales in China, J. Hydrometeorol., 9, 549-562, 2008.
76. Zribi, M., Pardé, M., Boutin, J., Fanise, P., Hauser, D., Dechambre, M., Kerr, Y., Leduc-Leballeur, M., Skou, M., Søbjærg, S. S., Albergel, C., Calvet, J.-C., Wigneron, J.-P., Lopez-Baeza, E., Ruis, A., and Tenerelli, J. CAROLS a new airborne L-band radiometer for ocean surface and land observations, Sensors, 11, 719-742, 2011.