Skip to main content
Log in

Estimating the soil moisture profile by assimilating near-surface observations with the ensemble Kaiman filter (EnKF)

  • Published:
Advances in Atmospheric Sciences Aims and scope Submit manuscript

Abstract

The paper investigates the ability to retrieve the true soil moisture profile by assimilating near-surface soil moisture into a soil moisture model with an ensemble Kaiman filter (EnKF) assimilation scheme, including the effect of ensemble size, update interval and nonlinearities in the profile retrieval, the required time for full retrieval of the soil moisture profiles, and the possible influence of the depth of the soil moisture observation. These questions are addressed by a desktop study using synthetic data. The “true” soil moisture profiles are generated from the soil moisture model under the boundary condition of 0.5 cm d−1 evaporation. To test the assimilation schemes, the model is initialized with a poor initial guess of the soil moisture profile, and different ensemble sizes are tested showing that an ensemble of 40 members is enough to represent the covariance of the model forecasts. Also compared are the results with those from the direct insertion assimilation scheme, showing that the EnKF is superior to the direct insertion assimilation scheme, for hourly observations, with retrieval of the soil moisture profile being achieved in 16 h as compared to 12 days or more. For daily observations, the true soil moisture profile is achieved in about 15 days with the EnKF, but it is impossible to approximate the true moisture within 18 days by using direct insertion. It is also found that observation depth does not have a significant effect on profile retrieval time for the EnKF. The nonlinearities have some negative influence on the optimal estimates of soil moisture profile but not very seriously.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

  • Anderson, J. L., 2001: An ensemble adjustment Kalman filter for data assimilation.Mon. Wea. Rev.,129, 2884–2903.

    Article  Google Scholar 

  • Bonan, G. B., 1996: A land surface model (LSM version 1.0) for ecological, hydrological, and atmospheric studies: Technical description and user’s guide. NCAR Tech. Note NCAR/TN-417+STR, 150pp.

  • Burgers, G., P. J. van Leeuwen, and G. Evensen, 1998: Analysis scheme in the ensemble Kalman Filter.Mon. Wea. Rev.,126, 1719–1724.

    Article  Google Scholar 

  • Celia, M. A., E. T. Bouloutas, and R. L. Zarba, 1990: A general mass conservative numerical solution for the unsaturated flow equation.Water Resour. Res.,26, 1483–1496.

    Article  Google Scholar 

  • Crow, W. T., and E. F. Wood, 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.Advances in Water Resources,26, 137–149.

    Article  Google Scholar 

  • Entekhabi, D., H. Nakamura, and E. G. Njoku, 1994: Solving the inverse problem for soil moisture and temperature profiles by sequential assimilation of multifrequency remotely sensed observations.IEEE Trans. Geosci. Remote Sens.,32, 438–448.

    Article  Google Scholar 

  • Erric, R. M., 1999: Workshop on assimilation of satellite data.Bull. Amer. Meteor. Soc.,80, 463–471.

    Google Scholar 

  • Erric, R. M., G. Ohring, J. Derber, and J. Hoiner, 2000: NOAA-NASA-DoD workshop on satellite data assimilation.Bull. Amer. Meteor. Soc.,81, 2457–2462.

    Article  Google Scholar 

  • Evensen, G., 1994: Sequential data assimilation with a non-linear quasi-geostrophic model using Monte Carlo methods to forecast error statistics.J. Geophys. Res.,99(C5), 10143–10162.

    Article  Google Scholar 

  • Evensen, G., 2003: The ensemble Kalman filter: Theoretical formulation and practical implementation.Ocean Dynamics,53, 343–367.

    Article  Google Scholar 

  • Galantowicz, J. F., D. Entekhabi, and E. G. Njoku, 1999: Test of sequential data assimilation for retrieving profile soil moisture and temperature from observed L-band radiobrightness.IEEE Trans. Geosci. and Remote Sens.,37(4), 1860–1870.

    Article  Google Scholar 

  • Guo Weidong, and Wang Huijun, 2003: A case study of the improvement of soil moisture initialization in IAP-PSSCA.Adv. Atmos. Sci.,20, 845–848.

    Article  Google Scholar 

  • Hamill, T. M., and J. S. Whitaker, 2001: Distance-dependent filtering of background error covariance estimates in an ensemble Kalman filter.Mon. Wea. Rev.,129, 2776–2790.

    Article  Google Scholar 

  • Houser, P. R., W. J. Shuttleworth, J. S. Famiglietti, H. V. Gupta, K. H. Syed, and D. C. Goodrich, 1998: Integration of soil moisture remote sensing and hydrologic modeling using data assimilation.Water Resour. Res.,34, 3405–3420.

    Article  Google Scholar 

  • Houtekamer, P. L., and H. L. Mitchell, 1998: Data assimilation using an ensemble Kalman filter technique.Mon. Wea. Rev.,126, 769–811.

    Article  Google Scholar 

  • Koster, R. D., M. J. Suarez, and M. Heiser, 2000: Variance and predictability of precipitation at seasonal to interannual timescales.Journal of Hydrometeorolog.,1, 26–46.

    Article  Google Scholar 

  • Li, J., and S. Islam, 1999: Estimation of soil moisture profile and surface fluxes partitioning from sequential assimilation of surface layer soil moisture.J. Hydrol.,220, 86–103.

    Article  Google Scholar 

  • Ma Zhuguo, Wei Helin, and Fu Congbin, 2000: Relationship between regional soil moisture variation and climatic variability over East China.Chinese J. Atmos. Sci.,58, 278–287.

    Google Scholar 

  • Njoku, E. G., and D. Entekhabi, 1995: Passive microwave remote sensing of soil moisture.J. Hydrol.,184, 101–130.

    Article  Google Scholar 

  • Owe, M., R. de Jeu, and J. Walker, 2001: A methodology for surface soil moisture and vegetation optical depth retrieval using the microwave polarization difference index.IEEE Geosci. Remote Sens.,39, 1643–1653.

    Article  Google Scholar 

  • Reichle, R. H., D. Entekhabi, and D. B. McLaughlin, 2001: Downscaling of radio brightness measurements for soil moisture estimation: A four-dimensional variational data assimilation approach.Water Resour. Res.,37, 2353–2364.

    Article  Google Scholar 

  • Reichle, R. H., D. B. McLaughlin, and D. Entekhabi, 2002a: Hydrologie data assimilation with the ensemble Kalman filter.Mon. Wea. Rev.,130, 103–114.

    Article  Google Scholar 

  • Reichle, R. H., J. P. Walker, R. D. Koster, and P. R. Houser, 2002b: Extended versus ensemble Kalman filtering for land data assimilation.Journal of Hydrometeorology,3, 728–740.

    Article  Google Scholar 

  • Schmugge, T. J., T. J. Jackson, H. L. McKim, 1980: Survey of methods for soil moisture determination.Water Resour. Res.,16, 961–979.

    Article  Google Scholar 

  • Versteeg, H. K., and W. Malalasekera, 1998:An Introduction to Computational Fluid Dynamics. Longman Group, 257pp.

  • Walker, J. P., G. R. Willgoose, and J. D. Kalma, 2001: One-dimensional soil moisture profile retrieval by assimilation of near-surface observations: A comparison of retrieval algorithms.Advances in Water Resources,24, 631–650.

    Article  Google Scholar 

  • Yeh, T. C., R. I. Wetherald, and S. Manabe, 1984: The effect of soil moisture on the short term climate and hydrology change—A numerical experiment.Mon. Wea. Rev.,112, 474–490.

    Article  Google Scholar 

  • Zhang, S.-W., C.-J. Qiu, and Q. Xu, 2004: Estimating soil water contents from soil temperature measurements by using an adaptive Kalman filter.J. Appl. Meteor.,43, 379–389.

    Article  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Zhang Shuwen.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Shuwen, Z., Haorui, L., Weidong, Z. et al. Estimating the soil moisture profile by assimilating near-surface observations with the ensemble Kaiman filter (EnKF). Adv. Atmos. Sci. 22, 936–945 (2005). https://doi.org/10.1007/BF02918692

Download citation

  • Received:

  • Revised:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF02918692

Key words

Navigation