Sensitivity of Latent Heat Fluxes to Initial Values and Parameters of a Land‐Surface Model

A tangent linear version of the complex soil–vegetaƟ on–atmosphere transfer model Community Land Model has been developed and its ability to reproduce relevant sensiƟ viƟ es of the modeled soil moisture and latent heat fl ux (LE) evoluƟ on to a number of diff erent parameters on a short Ɵ me scale (3 d) was analyzed. To this end, a series of idealized experiments for diff erent soil moisture states and three diff erent soil types was conducted. We found that the tangent linear model performs well for a large range of condiƟ ons. SituaƟ ons in which the linear approximaƟ on potenƟ ally fails were connected with the occurrence of saturaƟ on and with the highly nonlinear parameterizaƟ on of water availability to plants. The sensiƟ vity of LE with respect to the model’s iniƟ al soil moisture state was calculated and compared with the LE sensiƟ vity to soil texture, leaf area index (LAI), and vegetaƟ on roughness length. These sensiƟ viƟ es were found to be highly variable with soil type and soil moisture. Our results confi rm that soil texture and LAI are key parameters that have a dominant infl uence on modeled LE under specifi c environmental condiƟ ons. As a preparatory study to soil data assimilaƟ on developments, the results also serve to quanƟ fy model uncertainƟ es due to limited knowledge of forcing processes and model parameters. AbbreviaƟ ons: 4D-Var, four-dimensional variaƟ onal; CLM, Community Land Model; LAI, leaf area index; LE, latent heat fl ux; PFT, plant funcƟ onal type; SVAT, soil –vegetaƟ on –atmosphere transfer.

[1]  J. Noilhan,et al.  Sensitivity study and validation of a land surface parameterization using the HAPEX-MOBILHY data set , 1990 .

[2]  Thomas Kaminski,et al.  Recipes for adjoint code construction , 1998, TOMS.

[3]  Andreas Rhodin,et al.  A case study on variational soil moisture analysis from atmospheric observations , 1998 .

[4]  P. Courtier,et al.  A strategy for operational implementation of 4D‐Var, using an incremental approach , 1994 .

[5]  Soroosh Sorooshian,et al.  Sensitivity analysis of a land surface scheme using multicriteria methods , 1999 .

[6]  D. Entekhabi.  RECENT ADVANCES IN LAND-ATMOSPHERE INTERACTION RESEARCH , 1995 .

[7]  Wilfried Brutsaert,et al.  Hydrology: An Introduction , 2005 .

[8]  Klaus Scipal,et al.  Towards a Kalman Filter based soil moisture analysis system for the operational ECMWF Integrated Forecast System , 2009 .

[9]  Ann Henderson-Sellers,et al.  Sensitivity of the biosphere-atmosphere transfer scheme (BATS) to the inclusion of variable soil characteristics , 1987 .

[10]  Randal D. Koster,et al.  The Sensitivity of Surface Fluxes to Soil Water Content in Three Land Surface Schemes , 2000 .

[11]  Hendrik Elbern,et al.  Emission rate and chemical state estimation by 4-dimensional variational inversion , 2007 .

[12]  Eugenia Kalnay,et al.  Atmospheric Modeling, Data Assimilation and Predictability , 2002 .

[13]  J. Pailleux,et al.  Variational surface analysis from screen level atmospheric parameters , 1999 .

[14]  Laurent Hascoët,et al.  TAPENADE 2.1 user's guide , 2004 .

[15]  Florence Rabier,et al.  Overview of global data assimilation developments in numerical weather‐prediction centres , 2005 .

[16]  Rolf Reichle,et al.  Variational data assimilation of microwave radiobrightness observations for land surface hydrology applications , 2001, IEEE Trans. Geosci. Remote. Sens..

[17]  Peter E. Thornton,et al.  Improvements to the Community Land Model and their impact on the hydrological cycle , 2008 .

[18]  Dafydd Gibbon,et al.  1 User’s guide , 1998 .

[19]  N. Gustafsson,et al.  Sensitivity experiments with the spectral HIRLAM and its adjoint , 1996 .

[20]  Zong-Liang Yang,et al.  Development of a simple groundwater model for use in climate models and evaluation with Gravity Recovery and Climate Experiment data , 2007 .

[21]  Steven A. Margulis,et al.  A Coupled Land Surface–Boundary Layer Model and Its Adjoint , 2001 .

[22]  William C. Skamarock,et al.  A time-split nonhydrostatic atmospheric model for weather research and forecasting applications , 2008, J. Comput. Phys..

[23]  G. Hornberger,et al.  Empirical equations for some soil hydraulic properties , 1978 .

[24]  M. Drusch,et al.  Assimilation of Screen-Level Variables in ECMWF’s Integrated Forecast System: A Study on the Impact on the Forecast Quality and Analyzed Soil Moisture , 2007 .

[25]  Forecasting the Surface Weather Elements with a Local Dynamical-Adaptation Method Using a Variational Technique , 1992 .

[26]  Ann Henderson-Sellers,et al.  A Factorial Assessment of the Sensitivity of the BATS Land-Surface Parameterization Scheme , 1993 .

[27]  F. Kucharski,et al.  Variational analysis of effective soil moisture from screen‐level atmospheric parameters: Application to a short‐range weather forecast model , 1999 .

[28]  Andrew J. Pitman,et al.  Assessing the Sensitivity of a Land-Surface Scheme to the Parameter Values Using a Single Column Model , 1994 .

[29]  J. Noilhan,et al.  A simplified bi‐dimensional variational analysis of soil moisture from screen‐level observations in a mesoscale numerical weather‐prediction model , 2004 .

[30]  D. McLaughlin,et al.  Hydrologic Data Assimilation with the Ensemble Kalman Filter , 2002 .

[31]  D. McLaughlin,et al.  Assessing the Performance of the Ensemble Kalman Filter for Land Surface Data Assimilation , 2006 .

[32]  J. Schwinger,et al.  Chemical state estimation for the middle atmosphere by four‐dimensional variational data assimilation: System configuration , 2010 .

[33]  T. Chase,et al.  Representing a new MODIS consistent land surface in the Community Land Model (CLM 3.0) , 2007 .

[34]  R. Hess,et al.  Assimilation of screen-level observations by variational soil moisture analysis , 2001 .

[35]  N. Verhoest,et al.  State and bias estimation for soil moisture profiles by an ensemble Kalman filter: Effect of assimilation depth and frequency , 2007 .

[36]  Luis A. Bastidas,et al.  Using a multiobjective approach to retrieve information on surface properties used in a SVAT model , 2004 .

[37]  Simon Chabrillat,et al.  4D-Var assimilation of MIPAS chemical observations: ozone and nitrogen dioxide analyses , 2008 .

[38]  Olivier Talagrand,et al.  Assimilation of Observations, an Introduction (gtSpecial IssueltData Assimilation in Meteology and Oceanography: Theory and Practice) , 1997 .

[39]  Keith W. Oleson,et al.  Simulation of Global Land Surface Conditions from 1948 to 2004. Part I: Forcing Data and Evaluations , 2006 .

[40]  J. M. Sabater,et al.  From near-surface to root-zone soil moisture using different assimilation techniques , 2007 .

[41]  Peter E. Thornton,et al.  Technical Description of the Community Land Model (CLM) , 2004 .

[42]  Soroosh Sorooshian,et al.  Exploring parameter sensitivities of the land surface using a locally coupled land-atmosphere model , 2004 .

[43]  Matthias Drusch,et al.  The Usage of Screen-Level Parameters and Microwave Brightness Temperature for Soil Moisture Analysis , 2004 .

[44]  G. Carmichael,et al.  Direct and adjoint sensitivity analysis of chemical kinetic systems with KPP: Part I—theory and software tools , 2003, Atmospheric Environment.

[45]  J. Lelieveld,et al.  In-situ measurement of reactive hydrocarbons at Hohenpeissenberg with comprehensive two-dimensional gas chromatography (GC×GC-FID): use in estimating HO and NO 3 , 2007 .

[46]  F. Bouttier,et al.  Sequential Assimilation of Soil Moisture from Atmospheric Low-Level Parameters. Part I: Sensitivity and Calibration Studies , 1993 .

[47]  H. A. R. De Bruin,et al.  A study of the sensitivity of land surface parameterizations to the inclusion of different fractional covers and soil textures. , 1992 .

[48]  Xu Liang,et al.  Intercomparison of land-surface parameterization schemes: sensitivity of surface energy and water fluxes to model parameters , 2003 .

[49]  Steven A. Margulis,et al.  Feedback between the Land Surface Energy Balance and Atmospheric Boundary Layer Diagnosed through a Model and Its Adjoint , 2001 .

[50]  F. Bouyssel,et al.  A comparison of two off‐line soil analysis schemes for assimilation of screen level observations , 2009 .

[51]  J. Mahfouf,et al.  Comparative Study of Various Formulations of Evaporations from Bare Soil Using In Situ Data , 1991 .

[52]  Soroosh Sorooshian,et al.  Sensitivity analysis of the biosphere‐atmosphere transfer scheme , 1996 .