Global Soil Moisture Estimation by Assimilating AMSR-E Brightness Temperatures in a Coupled CLM4–RTM–DART System

Long Zhao Department of Geological Sciences, Jackson School of Geosciences, The University of Texas at Austin, Austin, Texas

Search for other papers by Long Zhao in
Current site
Google Scholar
PubMed
Close
,
Zong-Liang Yang Department of Geological Sciences, Jackson School of Geosciences, The University of Texas at Austin, Austin, Texas

Search for other papers by Zong-Liang Yang in
Current site
Google Scholar
PubMed
Close
, and
Timothy J. Hoar National Center for Atmospheric Research, Boulder, Colorado

Search for other papers by Timothy J. Hoar in
Current site
Google Scholar
PubMed
Close
Restricted access

Abstract

Very few frameworks exist that estimate global-scale soil moisture through microwave land data assimilation (DA). Toward this goal, such a framework has been developed by linking the Community Land Model, version 4 (CLM4), and a microwave radiative transfer model (RTM) with the Data Assimilation Research Testbed (DART). The deterministic ensemble adjustment Kalman filter (EAKF) within DART is utilized to estimate global multilayer soil moisture by assimilating brightness temperature observations from the Advanced Microwave Scanning Radiometer for Earth Observing System (AMSR-E). A 40-member ensemble of Community Atmosphere Model, version 4.0 (CAM4.0), reanalysis is adopted to drive CLM4 simulations. Space-specific, time-invariant microwave parameters are precalibrated to minimize uncertainties in RTM. Besides, various methods are designed to upscale AMSR-E observations for computational efficiency and time shift CAM4.0 forcing to facilitate global daily assimilations. A series of experiments are conducted to quantify the DA sensitivity to microwave parameters, choice of assimilated observations, and different CLM4 updating schemes. Evaluation results indicate that the newly established CLM4–RTM–DART framework improves the open-loop CLM4-simulated soil moisture. Precalibrated microwave parameters, rather than their default values, can ensure a more robust global-scale performance. In addition, updating near-surface soil moisture is capable of improving soil moisture in deeper layers (0–30 cm), while simultaneously updating multilayer soil moisture fails to obtain intended improvements. Future work is needed to address the systematic bias in CLM4 that cannot be fully covered through the ensemble spread in CAM4.0 reanalysis.

Corresponding author address: Zong-Liang Yang, Department of Geological Sciences, Jackson School of Geosciences, The University of Texas at Austin, 1 University Station, #C1100, Austin, TX 78712-0254. E-mail: liang@jsg.utexas.edu

Abstract

Very few frameworks exist that estimate global-scale soil moisture through microwave land data assimilation (DA). Toward this goal, such a framework has been developed by linking the Community Land Model, version 4 (CLM4), and a microwave radiative transfer model (RTM) with the Data Assimilation Research Testbed (DART). The deterministic ensemble adjustment Kalman filter (EAKF) within DART is utilized to estimate global multilayer soil moisture by assimilating brightness temperature observations from the Advanced Microwave Scanning Radiometer for Earth Observing System (AMSR-E). A 40-member ensemble of Community Atmosphere Model, version 4.0 (CAM4.0), reanalysis is adopted to drive CLM4 simulations. Space-specific, time-invariant microwave parameters are precalibrated to minimize uncertainties in RTM. Besides, various methods are designed to upscale AMSR-E observations for computational efficiency and time shift CAM4.0 forcing to facilitate global daily assimilations. A series of experiments are conducted to quantify the DA sensitivity to microwave parameters, choice of assimilated observations, and different CLM4 updating schemes. Evaluation results indicate that the newly established CLM4–RTM–DART framework improves the open-loop CLM4-simulated soil moisture. Precalibrated microwave parameters, rather than their default values, can ensure a more robust global-scale performance. In addition, updating near-surface soil moisture is capable of improving soil moisture in deeper layers (0–30 cm), while simultaneously updating multilayer soil moisture fails to obtain intended improvements. Future work is needed to address the systematic bias in CLM4 that cannot be fully covered through the ensemble spread in CAM4.0 reanalysis.

Corresponding author address: Zong-Liang Yang, Department of Geological Sciences, Jackson School of Geosciences, The University of Texas at Austin, 1 University Station, #C1100, Austin, TX 78712-0254. E-mail: liang@jsg.utexas.edu
Save
  • Al-Yaari, A., and Coauthors, 2014: Global-scale evaluation of two satellite-based passive microwave soil moisture datasets (SMOS and AMSR-E) with respect to land data assimilation system estimates. Remote Sens. Environ., 149, 181195, doi:10.1016/j.rse.2014.04.006.

    • Search Google Scholar
    • Export Citation
  • Anderson, J., 2001: An ensemble adjustment Kalman filter for data assimilation. Mon. Wea. Rev., 129, 28842903, doi:10.1175/1520-0493(2001)129<2884:AEAKFF>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Anderson, J., Hoar T. , Raeder K. , Liu H. , Collins N. , Torn R. , and Avellano A. , 2009: The Data Assimilation Research Testbed: A community facility. Bull. Amer. Meteor. Soc., 90, 12831296, doi:10.1175/2009BAMS2618.1.

    • Search Google Scholar
    • Export Citation
  • Bao, Q., Liu Y. , Shi J. , and Wu G. , 2010: Comparisons of soil moisture datasets over the Tibetan Plateau and application to the simulation of Asia summer monsoon onset. Adv. Atmos. Sci., 27, 303314, doi:10.1007/s00376-009-8132-5.

    • Search Google Scholar
    • Export Citation
  • Blum, A., 2005: Drought resistance, water-use efficiency, and yield potential—Are they compatible, dissonant, or mutually exclusive? Aust. J. Agric. Res., 56, 11591168, doi:10.1071/AR05069.

    • Search Google Scholar
    • Export Citation
  • Bolten, J. D., Crow W. T. , Zhan X. W. , Jackson T. J. , and Reynolds C. A. , 2010: Evaluating the utility of remotely sensed soil moisture retrievals for operational agricultural drought monitoring. IEEE J. Sel. Top. Appl. Earth Obs. Remote Sens., 3, 5766, doi:10.1109/JSTARS.2009.2037163.

    • Search Google Scholar
    • Export Citation
  • Cai, X., Yang Z.-L. , Xia Y. , Huang M. , Wei H. , Leung L. R. , and Ek M. B. , 2014: Assessment of simulated water balance from Noah, Noah-MP, CLM, and VIC over CONUS using the NLDAS test bed. J. Geophys. Res. Atmos., 119, 13 75113 770, doi:10.1002/2014JD022113.

    • Search Google Scholar
    • Export Citation
  • Changnon, S. A., 1987: Detecting drought conditions in Illinois. ISWS/CIR-169/87, Illinois State Water Survey, 36 pp. [Available online at http://www.sws.uiuc.edu/pubdoc/C/ISWSC-169.pdf.]

  • Chen, Y., Yang K. , Qin J. , Zhao L. , Tang W. , and Han M. , 2013: Evaluation of AMSR-E retrievals and GLDAS simulations against observations of a soil moisture network on the central Tibetan Plateau. J. Geophys. Res. Atmos., 118, 44664475, doi:10.1002/jgrd.50301.

    • Search Google Scholar
    • Export Citation
  • Clapp, R. B., and Hornberger G. M. , 1978: Empirical equations for some soil hydraulic properties. Water Resour. Res., 14, 601604, doi:10.1029/WR014i004p00601.

    • Search Google Scholar
    • Export Citation
  • Cosby, B. J., Hornberger G. M. , Clapp R. B. , and Ginn T. R. , 1984: A statistical exploration of the relationships of soil moisture characteristics to the physical properties of soils. Water Resour. Res., 20, 682690, doi:10.1029/WR020i006p00682.

    • Search Google Scholar
    • Export Citation
  • Crow, W. T., and Wood E. F. , 2003: The assimilation of remotely sensed soil brightness temperature imagery into a land surface model using ensemble Kalman filtering: A case study based on ESTAR measurements during SGP97. Adv. Water Resour., 26, 137149, doi:10.1016/S0309-1708(02)00088-X.

    • Search Google Scholar
    • Export Citation
  • Crow, W. T., and Van den Berg M. J. , 2010: An improved approach for estimating observation and model error parameters in soil moisture data assimilation. Water Resour. Res., 46, W12519, doi:10.1029/2010WR009402.

    • Search Google Scholar
    • Export Citation
  • Crow, W. T., and Coauthors, 2012: Upscaling sparse ground-based soil moisture observations for the validation of coarse-resolution satellite soil moisture products. Rev. Geophys., 50, RG2002, doi:10.1029/2011RG000372.

    • Search Google Scholar
    • Export Citation
  • Dai, A., Trenberth K. E. , and Qian T. T. , 2004: A global dataset of Palmer drought severity index for 1870–2002: Relationship with soil moisture and effects of surface warming. J. Hydrometeor., 5, 11171130, doi:10.1175/JHM-386.1.

    • Search Google Scholar
    • Export Citation
  • de Goncalves, L. G. G., Shuttleworth W. J. , Chou S. C. , Xue Y. , Houser P. R. , Toll D. L. , Marengo J. , and Rodell M. , 2006: Impact of different initial soil moisture fields on Eta model weather forecasts for South America. J. Geophys. Res., 111, D17102, doi:10.1029/2005JD006309.

    • Search Google Scholar
    • Export Citation
  • De Lannoy, G. J. M., and Reichle R. H. , 2016: Global assimilation of multiangle and multipolarization SMOS brightness temperature observations into the GEOS-5 catchment land surface model for soil moisture estimation. J. Hydrometeor., 17, 669691, doi:10.1175/JHM-D-15-0037.1.

    • Search Google Scholar
    • Export Citation
  • De Lannoy, G. J. M., Houser P. R. , Pauwels V. R. N. , and Verhoest N. E. C. , 2006: Assessment of model uncertainty for soil moisture through ensemble verification. J. Geophys. Res., 111, D10101, doi:10.1029/2005JD006367.

    • Search Google Scholar
    • Export Citation
  • De Lannoy, G. J. M., Houser P. R. , Pauwels V. R. N. , and Verhoest N. E. C. , 2007: State and bias estimation for soil moisture profiles by an ensemble Kalman filter: Effect of assimilation depth and frequency. Water Resour. Res., 43, W06401, doi:10.1029/2006WR005100.

    • Search Google Scholar
    • Export Citation
  • De Lannoy, G. J. M., Reichle R. H. , and Pauwels V. R. N. , 2013: Global calibration of the GEOS-5 L-band microwave radiative transfer model over nonfrozen land using SMOS observations. J. Hydrometeor., 14, 765785, doi:10.1175/JHM-D-12-092.1.

    • Search Google Scholar
    • Export Citation
  • De Lannoy, G. J. M., Reichle R. H. , and Vrugt J. A. , 2014: Uncertainty quantification of GEOS-5 L-band radiative transfer model parameters using Bayesian inference and SMOS observations. Remote Sens. Environ., 148, 146157, doi:10.1016/j.rse.2014.03.030.

    • Search Google Scholar
    • Export Citation
  • de Rosnay, P., and Coauthors, 2009: AMMA Land Surface Model Intercomparison Experiment coupled to the Community Microwave Emission Model: ALMIP–MEM. J. Geophys. Res., 114, D05108, doi:10.1029/2008JD010724.

    • Search Google Scholar
    • Export Citation
  • Dirmeyer, P. A., Gao X. , Zhao M. , Guo Z. , Oki T. , and Hanasaki N. , 2006: GSWP-2: Multimodel analysis and implications for our perception of the land surface. Bull. Amer. Meteor. Soc., 87, 13811397, doi:10.1175/BAMS-87-10-1381.

    • Search Google Scholar
    • Export Citation
  • Dobriyal, P., Qureshi A. , Badola R. , and Hussain S. A. , 2012: A review of the methods available for estimating soil moisture and its implications for water resource management. J. Hydrol., 458–459, 110117, doi:10.1016/j.jhydrol.2012.06.021.

    • Search Google Scholar
    • Export Citation
  • Dobson, M. C., Ulaby F. T. , Hallikainen M. T. , and El-Rayes M. A. , 1985: Microwave dielectric behavior of wet soil—Part II: Dielectric mixing models. IEEE Trans. Geosci. Remote Sens., 23, 3546, doi:10.1109/TGRS.1985.289498.

    • Search Google Scholar
    • Export Citation
  • Dorigo, W. A., and Coauthors, 2011: The International Soil Moisture Network: A data hosting facility for global in situ soil moisture measurements. Hydrol. Earth Syst. Sci., 15, 16751698, doi:10.5194/hess-15-1675-2011.

    • Search Google Scholar
    • Export Citation
  • Draper, C. S., Reichle R. H. , De Lannoy G. J. M. , and Liu Q. , 2012: Assimilation of passive and active microwave soil moisture retrievals. Geophys. Res. Lett., 39, L04401, doi:10.1029/2011GL050655.

    • Search Google Scholar
    • Export Citation
  • Drusch, M., 2007: Initializing numerical weather prediction models with satellite-derived surface soil moisture: Data assimilation experiments with ECMWF’s Integrated Forecast System and the TMI soil moisture data set. J. Geophys. Res., 112, D03102, doi:10.1029/2006JD007478.

    • Search Google Scholar
    • Export Citation
  • Du, E., Vittorio A. D. , and Collins B. , 2014: Historical evaluation of hydrologic components of CLM4: Surface soil water content and runoff. 2014 CESM Land Model Working Group Meeting, Boulder, CO, NCAR, 20 pp. [Available online at http://www.cesm.ucar.edu/working_groups/Land/Presentations/2014/du.pdf.]

  • Duan, Q. Y., Gupta V. K. , and Sorooshian S. , 1993: Shuffled complex evolution approach for effective and efficient global minimization. J. Optim. Theory Appl., 76, 501521, doi:10.1007/BF00939380.

    • Search Google Scholar
    • Export Citation
  • Entin, J. K., Robock A. , Vinnikov K. Y. , Zabelin V. , Liu S. , Namkhai A. , and Adyasuren T. , 1999: Evaluation of global soil wetness project soil moisture simulations. J. Meteor. Soc. Japan, 77, 183198.

    • Search Google Scholar
    • Export Citation
  • Fujii, H., 2005: Development of a microwave radiative transfer model for vegetated land surface based on comprehensive in-situ observations. Ph.D. thesis, University of Tokyo, 128 pp.

  • Han, X., Franssen H.-J. H. , Montzka C. , and Vereecken H. , 2014: Soil moisture and soil properties estimation in the Community Land Model with synthetic brightness temperature observations. Water Resour. Res., 50, 60816105, doi:10.1002/2013WR014586.

    • Search Google Scholar
    • Export Citation
  • Harding, R. J., Weedon G. P. , van Lanen H. A. J. , and Clark D. B. , 2014: The future for global water assessment. J. Hydrol., 518, 186193, doi:10.1016/j.jhydrol.2014.05.014.

    • Search Google Scholar
    • Export Citation
  • Henderson-Sellers, A., Yang Z. L. , and Dickinson R. E. , 1993: The Project for Intercomparison of Land-Surface Parameterization Schemes. Bull. Amer. Meteor. Soc., 74, 13351349, doi:10.1175/1520-0477(1993)074<1335:TPFIOL>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Hurrell, J. W., and Coauthors, 2013: The Community Earth System Model: A framework for collaborative research. Bull. Amer. Meteor. Soc., 94, 13391360, doi:10.1175/BAMS-D-12-00121.1.

    • Search Google Scholar
    • Export Citation
  • Jackson, T. J., and Schmugge T. J. , 1991: Vegetation effects on the microwave emission of soils. Remote Sens. Environ., 36, 203212, doi:10.1016/0034-4257(91)90057-D.

    • Search Google Scholar
    • Export Citation
  • Jackson, T. J., and Coauthors, 2010: Validation of Advanced Microwave Scanning Radiometer soil moisture products. IEEE Trans. Geosci. Remote Sens., 48, 42564272, doi:10.1109/TGRS.2010.2051035.

    • Search Google Scholar
    • Export Citation
  • Kerr, Y., 2007: Soil moisture from space: Where are we? Hydrogeol. J., 15, 117120, doi:10.1007/s10040-006-0095-3.

  • Kluzek, E., 2013: CESM Research Tools: CLM4 in CESM1.1.1 user's guide documentation. NCAR, 147 pp. [Available online at http://www.cesm.ucar.edu/models/cesm1.1/clm/models/lnd/clm/doc/UsersGuide/clm_ug.pdf.]

  • Knowles, K. W., Savoie M. H. , Armstrong R. L. , and Brodzik M. J. , 2011: AMSR-E/Aqua daily global quarter-degree gridded brightness temperatures. Subset used: 1 June 2010 to 1 October 2010. National Snow and Ice Data Center, accessed 10 September 2013, doi:10.5067/RRR4WWORG070.

  • Kumar, S. V., Reichle R. H. , Koster R. D. , Crow W. T. , and Peters-Lidard C. D. , 2009: Role of subsurface physics in the assimilation of surface soil moisture observations. J. Hydrometeor., 10, 15341547, doi:10.1175/2009JHM1134.1.

    • Search Google Scholar
    • Export Citation
  • Kumar, S. V., Reichle R. H. , Harrison K. W. , Peters-Lidard C. D. , Yatheendradas S. , and Santanello J. A. , 2012: A comparison of methods for a priori bias correction in soil moisture data assimilation. Water Resour. Res., 48, W03515, doi:10.1029/2010WR010261.

    • Search Google Scholar
    • Export Citation
  • Kwon, Y., Toure A. M. , Yang Z. L. , Rodell M. , and Picard G. , 2015: Error characterization of coupled land surface–radiative transfer models for snow microwave radiance assimilation. IEEE Trans. Geosci. Remote Sens., 53, 52475268, doi:10.1109/TGRS.2015.2419977.

    • Search Google Scholar
    • Export Citation
  • Lakshmi, V., Wood E. F. , and Choudhury B. J. , 1997: Investigation of effect of heterogeneities in vegetation and rainfall on simulated SSM/I brightness temperatures. Int. J. Remote Sens., 18, 27632784, doi:10.1080/014311697217323.

    • Search Google Scholar
    • Export Citation
  • Lawrence, D. M., and Slater A. G. , 2008: Incorporating organic soil into a global climate model. Climate Dyn., 30, 145160, doi:10.1007/s00382-007-0278-1.

    • Search Google Scholar
    • Export Citation
  • Lawrence, D. M., and Coauthors, 2011: Parameterization improvements and functional and structural advances in version 4 of the Community Land Model. J Adv. Model. Earth Syst., 3, M03001, doi:10.1029/2011MS000045.

    • Search Google Scholar
    • Export Citation
  • Lawrence, P. J., and Chase T. N. , 2007: Representing a new MODIS consistent land surface in the Community Land Model (CLM 3.0). J. Geophys. Res., 112, G01023, doi:10.1029/2006JG000168.

    • Search Google Scholar
    • Export Citation
  • Liang, S., and Qin J. , 2008: Data assimilation methods for land surface variable estimation. Advances in Land Remote Sensing, S. Liang, Ed., Springer, 313–339, doi:10.1007/978-1-4020-6450-0_12.

  • Liang, S., and Xiao Z. , 2012: Global land surface products: Leaf area index product data collection (1985–2010). Beijing Normal University, accessed 28 July 2014, doi:10.6050/glass863.3004.db.

  • Loew, A., Schwank M. , and Schlenz F. , 2009: Assimilation of an L-band microwave soil moisture proxy to compensate for uncertainties in precipitation data. IEEE Trans. Geosci. Remote Sens., 47, 26062616, doi:10.1109/TGRS.2009.2014846.

    • Search Google Scholar
    • Export Citation
  • Loew, A., Stacke T. , Dorigo W. , de Jeu R. , and Hagemann S. , 2013: Potential and limitations of multidecadal satellite soil moisture observations for selected climate model evaluation studies. Hydrol. Earth Syst. Sci., 17, 35233542, doi:10.5194/hess-17-3523-2013.

    • Search Google Scholar
    • Export Citation
  • Long, D., Scanlon B. R. , Longuevergne L. , Sun A. Y. , Fernando D. N. , and Save H. , 2013: GRACE satellite monitoring of large depletion in water storage in response to the 2011 drought in Texas. Geophys. Res. Lett., 40, 33953401, doi:10.1002/grl.50655.

    • Search Google Scholar
    • Export Citation
  • Margulis, S. A., McLaughlin D. , Entekhabi D. , and Dunne S. , 2002: Land data assimilation and estimation of soil moisture using measurements from the Southern Great Plains 1997 Field Experiment. Water Resour. Res., 38, 1299, doi:10.1029/2001WR001114.

    • Search Google Scholar
    • Export Citation
  • Montzka, C., Moradkhani H. , Weihermuller L. , Franssen H. J. H. , Canty M. , and Vereecken H. , 2011: Hydraulic parameter estimation by remotely-sensed top soil moisture observations with the particle filter. J. Hydrol., 399, 410421, doi:10.1016/j.jhydrol.2011.01.020.

    • Search Google Scholar
    • Export Citation
  • Moradkhani, H., Sorooshian S. , Gupta H. V. , and Houser P. R. , 2005: Dual state-parameter estimation of hydrological models using ensemble Kalman filter. Adv. Water Resour., 28, 135147, doi:10.1016/j.advwatres.2004.09.002.

    • Search Google Scholar
    • Export Citation
  • Nie, S., Zhu J. , and Luo Y. , 2011: Simultaneous estimation of land surface scheme states and parameters using the ensemble Kalman filter: Identical twin experiments. Hydrol. Earth Syst. Sci., 15, 24372457, doi:10.5194/hess-15-2437-2011.

    • Search Google Scholar
    • Export Citation
  • Njoku, E. G., Ashcroft P. , Chan T. K. , and Li L. , 2005: Global survey and statistics of radio-frequency interference in AMSR-E land observations. IEEE Trans. Geosci. Remote Sens., 43, 938947, doi:10.1109/TGRS.2004.837507.

    • Search Google Scholar
    • Export Citation
  • Oleson, K. W., and Coauthors, 2004: Technical description of the Community Land Model (CLM). NCAR Tech. Note NCAR/TN-461+STR, 173 pp., doi:10.5065/D6N877R0.

  • Oleson, K. W., and Coauthors, 2010: Technical description of version 4.0 of the Community Land Model (CLM). NCAR Tech. Note NCAR/TN-478+STR, 257 pp., doi:10.5065/D6FB50WZ.

  • Paloscia, S., and Pampaloni P. , 1988: Microwave polarization index for monitoring vegetation growth. IEEE Trans. Geosci. Remote Sens., 26, 617621, doi:10.1109/36.7687.

    • Search Google Scholar
    • Export Citation
  • Pan, M., and Wood E. F. , 2006: Data assimilation for estimating the terrestrial water budget using a constrained ensemble Kalman filter. J. Hydrometeor., 7, 534547, doi:10.1175/JHM495.1.

    • Search Google Scholar
    • Export Citation
  • Prigent, C., Aires F. , Rossow W. B. , and Robock A. , 2005: Sensitivity of satellite microwave and infrared observations to soil moisture at a global scale: Relationship of satellite observations to in situ soil moisture measurements. J. Geophys. Res., 110, D07110, doi:10.1029/2004JD005087.

    • Search Google Scholar
    • Export Citation
  • Qin, J., Liang S. L. , Yang K. , Kaihotsu I. , Liu R. G. , and Koike T. , 2009: Simultaneous estimation of both soil moisture and model parameters using particle filtering method through the assimilation of microwave signal. J. Geophys. Res., 114, D15103, doi:10.1029/2008JD011358.

    • Search Google Scholar
    • Export Citation
  • Raeder, K., Anderson J. L. , Collins N. , Hoar T. J. , Kay J. E. , Lauritzen P. H. , and Pincus R. , 2012: DART/CAM: An ensemble data assimilation system for CESM atmospheric models. J. Climate, 25, 63046317, doi:10.1175/JCLI-D-11-00395.1.

    • Search Google Scholar
    • Export Citation
  • Reichle, R. H., 2008: Data assimilation methods in the earth sciences. Adv. Water Resour., 31, 14111418, doi:10.1016/j.advwatres.2008.01.001.

    • Search Google Scholar
    • Export Citation
  • Reichle, R. H., and Koster R. D. , 2004: Bias reduction in short records of satellite soil moisture. Geophys. Res. Lett., 31, L19501, doi:10.1029/2004GL020938.

    • Search Google Scholar
    • Export Citation
  • Reichle, R. H., McLaughlin D. B. , and Entekhabi D. , 2002: Hydrologic data assimilation with the ensemble Kalman filter. Mon. Wea. Rev., 130, 103114, doi:10.1175/1520-0493(2002)130<0103:HDAWTE>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Reichle, R. H., Koster R. D. , Liu P. , Mahanama S. P. P. , Njoku E. G. , and Owe M. , 2007: Comparison and assimilation of global soil moisture retrievals from the Advanced Microwave Scanning Radiometer for the Earth Observing System (AMSR-E) and the Scanning Multichannel Microwave Radiometer (SMMR). J. Geophys. Res., 112, D09108, doi:10.1029/2006JD008033.

    • Search Google Scholar
    • Export Citation
  • Reichle, R. H., Crow W. T. , and Keppenne C. L. , 2008: An adaptive ensemble Kalman filter for soil moisture data assimilation. Water Resour. Res., 44, W03423, doi:10.1029/2007WR006357.

    • Search Google Scholar
    • Export Citation
  • Reichle, R. H., Bosilovich M. G. , Crow W. T. , Koster R. D. , Kumar S. V. , Mahanama S. P. , and Zaitchik B. F. , 2009: Recent advances in land data assimilation at the NASA Global Modeling and Assimilation Office. Data Assimilation for Atmospheric, Oceanic and Hydrologic Applications, S. K. Park and L. Xu, Eds., Springer, 407–428, doi:10.1007/978-3-540-71056-1.

  • Reichle, R. H., De Lannoy G. J. M. , Forman B. A. , Draper C. S. , and Liu Q. , 2014: Connecting satellite observations with water cycle variables through land data assimilation: Examples using the NASA GEOS-5 LDAS. Surv. Geophys., 35, 577606, doi:10.1007/s10712-013-9220-8.

    • Search Google Scholar
    • Export Citation
  • Robinson, D. A., and Coauthors, 2008: Soil moisture measurement for ecological and hydrological watershed-scale observatories: A review. Vadose Zone J., 7, 358389, doi:10.2136/vzj2007.0143.

    • Search Google Scholar
    • Export Citation
  • Romano, N., 2014: Soil moisture at local scale: Measurements and simulations. J. Hydrol., 516, 620, doi:10.1016/j.jhydrol.2014.01.026.

    • Search Google Scholar
    • Export Citation
  • Sellers, P. J., and Coauthors, 1996: A revised land surface parameterization (SiB2) for atmospheric GCMs. Part I: Model formulation. J. Climate, 9, 676705, doi:10.1175/1520-0442(1996)009<0676:ARLSPF>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Shi, X., Wen J. , Wang L. , Zhang T. , Tian H. , Wang X. , Liu R. , and Zhang J. , 2010: Regional soil moisture retrievals and simulations from assimilation of satellite microwave brightness temperature observations. Environ. Earth Sci., 61, 12891299, doi:10.1007/s12665-010-0504-8.

    • Search Google Scholar
    • Export Citation
  • Su, Z., Wen J. , Dente L. , van der Velde R. , Wang L. , Ma Y. , Yang K. , and Hu Z. , 2011: The Tibetan Plateau observatory of plateau scale soil moisture and soil temperature (Tibet-Obs) for quantifying uncertainties in coarse resolution satellite and model products. Hydrol. Earth Syst. Sci., 15, 23032316, doi:10.5194/hess-15-2303-2011.

    • Search Google Scholar
    • Export Citation
  • Tian, X., Xie Z. , and Dai A. , 2008: A land surface soil moisture data assimilation system based on the dual-UKF method and the Community Land Model. J. Geophys. Res., 113, D14127, doi:10.1029/2007JD009650.

    • Search Google Scholar
    • Export Citation
  • Tian, X., Xie Z. , Dai A. , Jia B. H. , and Shi C. X. , 2010: A microwave land data assimilation system: Scheme and preliminary evaluation over China. J. Geophys. Res., 115, D21113, doi:10.1029/2010JD014370.

    • Search Google Scholar
    • Export Citation
  • Tian, X., Xie Z. , and Sun Q. , 2011: A POD-based ensemble four-dimensional variational assimilation method. Tellus, 63A, 805816, doi:10.1111/j.1600-0870.2011.00529.x.

    • Search Google Scholar
    • Export Citation
  • Ulaby, F. T., Moore R. K. , and Fung A. K. , 1986: Microwave Remote Sensing Active and Passive—Volume III: From Theory to Applications. Artech House, 2162 pp.

  • Vereecken, H., Huisman J. A. , Bogena H. , Vanderborght J. , Vrugt J. A. , and Hopmans J. W. , 2008: On the value of soil moisture measurements in vadose zone hydrology: A review. Water Resour. Res., 44, W00D06, doi:10.1029/2008WR006829.

    • Search Google Scholar
    • Export Citation
  • Vinnikov, K. Y., Robock A. , Qiu S. , Entin J. K. , Owe M. , Choudhury B. J. , Hollinger S. E. , and Njoku E. G. , 1999: Satellite remote sensing of soil moisture in Illinois, United States. J. Geophys. Res., 104, 41454168, doi:10.1029/1998JD200054.

    • Search Google Scholar
    • Export Citation
  • Wang, J. R., and Choudhury B. J. , 1981: Remote sensing of soil moisture content over bare field at 1.4 GHz frequency. J. Geophys. Res., 86, 52775282, doi:10.1029/JC086iC06p05277.

    • Search Google Scholar
    • Export Citation
  • Wegmuller, U., and Matzler C. , 1999: Rough bare soil reflectivity model. IEEE Trans. Gesoci. Remote Sens., 37, 13911395, doi:10.1109/36.763303.

    • Search Google Scholar
    • Export Citation
  • Xia, Y., Sheffield J. , Ek M. B. , Dong J. , Chaney N. , Wei H. , Meng J. , and Wood E. F. , 2014: Evaluation of multi-model simulated soil moisture in NLDAS-2. J. Hydrol., 512, 107125, doi:10.1016/j.jhydrol.2014.02.027.

    • Search Google Scholar
    • Export Citation
  • Xiao, Z., Liang S. , Wang J. , Chen P. , Yin X. , Zhang L. , and Song J. , 2014: Use of general regression neural networks for generating the GLASS leaf area index product from time-series MODIS surface reflectance. IEEE Trans. Gesoci. Remote Sens., 52, 209223, doi:10.1109/TGRS.2013.2237780.

    • Search Google Scholar
    • Export Citation
  • Yang, K., and Coauthors, 2007: Auto-calibration system developed to assimilate AMSR-E data into a land surface model for estimating soil moisture and the surface energy budget. J. Meteor. Soc. Japan, 85A, 229242, doi:10.2151/jmsj.85A.229.

    • Search Google Scholar
    • Export Citation
  • Yang, K., Koike T. , Kaihotsu I. , and Qin J. , 2009: Validation of a dual-pass microwave land data assimilation system for estimating surface soil moisture in semiarid regions. J. Hydrometeor., 10, 780793, doi:10.1175/2008JHM1065.1.

    • Search Google Scholar
    • Export Citation
  • Zeng, X., and Decker M. , 2009: Improving the numerical solution of soil moisture–based Richards equation for land models with a deep or shallow water table. J. Hydrometeor., 10, 308319, doi:10.1175/2008JHM1011.1.

    • Search Google Scholar
    • Export Citation
  • Zhang, S. L., Shi J. C. , and Dou Y. J. , 2012: A soil moisture assimilation scheme based on the microwave Land Emissivity Model and the Community Land Model. Int. J. Remote Sens., 33, 27702797, doi:10.1080/01431161.2011.620032.

    • Search Google Scholar
    • Export Citation
  • Zhang, Y.-F., 2015: Multivariate land snow data assimilation in the Northern Hemisphere: Development, evaluation and uncertainty quantification of the extensible data assimilation system. Ph.D. dissertation, The University of Texas at Austin, 138 pp. [Available online at https://repositories.lib.utexas.edu/handle/2152/32613.]

  • Zhang, Y.-F., Hoar T. J. , Yang Z.-L. , Anderson J. L. , Toure A. M. , and Rodell M. , 2014: Assimilation of MODIS snow cover through the Data Assimilation Research Testbed and the Community Land Model version 4. J. Geophys. Res. Atmos., 119, 70917103, doi:10.1002/2013JD021329.

    • Search Google Scholar
    • Export Citation
  • Zhao, L., Yang K. , Qin J. , and Chen Y. , 2013: Optimal exploitation of AMSR-E signals for improving soil moisture estimation through land data assimilation. IEEE Trans. Geosci. Remote Sens., 51, 399410, doi:10.1109/TGRS.2012.2198483.

    • Search Google Scholar
    • Export Citation
All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 1330 765 68
PDF Downloads 394 76 8