Journal cover Journal topic
Hydrology and Earth System Sciences An interactive open-access journal of the European Geosciences Union
doi:10.5194/hess-2016-432
© Author(s) 2016. This work is distributed
under the Creative Commons Attribution 3.0 License.
Research article
26 Aug 2016
Review status
A revision of this discussion paper was accepted for the journal Hydrology and Earth System Sciences (HESS) and is expected to appear here in due course.
Evaluating the value of a network of cosmic-ray probes for improving land surface modelling
R. Baatz1,2, Harrie-Jan Hendricks Franssen1,2, Xujun Han1,2, Tim Hoar3, Heye R. Bogena1, and Harry Vereecken1,2 1Agrosphere (IBG-3), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
2HPSC-TerrSys, 52425 Jülich, Germany
3NCAR Data Assimilation Research Section, Boulder, CO, USA
Abstract. Land surface models can model matter and energy fluxes between the land surface and atmosphere, and provide a lower boundary condition to atmospheric circulation models. For these applications, accurate soil moisture quantification is highly desirable but not always possible given limited observations and limited subsurface data accuracy. Cosmic-ray probes (CRPs) offer an interesting alternative to indirectly measure soil moisture and provide an observation that can be assimilated into land surface models for improved soil moisture prediction. Synthetic studies have shown the potential to estimate subsurface parameters of land surface models with the assimilation of CRP observations. In this study, the potential of a network of CRPs for estimating subsurface parameters and improved soil moisture states is tested in a real-world case scenario using the local ensemble transform Kalman filter with the Community Land Model. The potential of the CRP network was tested by assimilating CRP-data for the years 2011 and 2012 (with or without soil hydraulic parameter estimation), followed by the verification year 2013. This was done using (i) the regional soil map as input information for the simulations, and (ii) an erroneous, biased soil map. For the regional soil map, soil moisture characterization was only improved in the assimilation period but not in the verification period. For the biased soil map, soil moisture characterization improved in both periods strongly from a ERMS of 0.11 cm3/cm3 to 0.03 cm3/cm3 (assimilation period) and from 0.12 cm3/cm3 to 0.05 cm3/cm3 (verification period) and the estimated soil hydraulic parameters were after assimilation closer to the ones of the regional soil map. Finally, the value of the CRP network was also evaluated with jackknifing data assimilation experiments. It was found that the CRP network is able to improve soil moisture estimates at locations between the assimilation sites from a ERMS of 0.12 cm3/cm3 to 0.06 cm3/cm3 (verification period), but again only if the initial soil map was biased.

Citation: Baatz, R., Hendricks Franssen, H.-J., Han, X., Hoar, T., Bogena, H. R., and Vereecken, H.: Evaluating the value of a network of cosmic-ray probes for improving land surface modelling, Hydrol. Earth Syst. Sci. Discuss., doi:10.5194/hess-2016-432, in review, 2016.
R. Baatz et al.
R. Baatz et al.

Viewed

Total article views: 235 (including HTML, PDF, and XML)

HTML PDF XML Total BibTeX EndNote
165 47 23 235 23 25

Views and downloads (calculated since 26 Aug 2016)

Cumulative views and downloads (calculated since 26 Aug 2016)

Viewed (geographical distribution)

Total article views: 235 (including HTML, PDF, and XML)

Thereof 234 with geography defined and 1 with unknown origin.

Country # Views %
  • 1

Saved

Discussed

Latest update: 27 Apr 2017
Publications Copernicus
Download
Short summary
Soil moisture is a major variable that affects regional climate, weather processes and hydrologic processes at the earth surface. In this study, real world soil moisture measurements were used to better characterize model states and parameters of a regional land surface model. The results show the potential of these measurement networks for improving states and parameters. It is suggested to widen the number of estimated parameters and to include global measurement networks in future studies.
Soil moisture is a major variable that affects regional climate, weather processes and...
Share