caa a22 4500 46793777X CHVBK 20180406153002.0 cr unu---uuuuu 170328e20060201xx s 000 0 eng 10.1007/s00703-005-0150-y doi (NATIONALLICENCE)springer-10.1007/s00703-005-0150-y Ren D. School of Meteorology, University of Oklahoma, Norman, Oklahoma, USA aut A modified Richards equation, its adjoint, and a new perspective on land data assimilation [Elektronische Daten] [D. Ren] Summary: Richards equation, which is the key relationship for addressing basic soil hydrological processes within the rhizosphere and constitutes the basis for multiple-layer soil hydrology models for meteorological studies, is modified to include two vegetation processes: the transpiration (daytime) and hydraulic lift (nighttime). The analytical form of the adjoint system is derived and can serve as the guideline for discrete forms, as implemented in a variety of multiple layer land surface models. The modified equation and its adjoint model may be used to address at least two types of inverse problems: estimation of the initial soil moisture contents from sparse observations of related quantities; and retrieval of critical soil/vegetation parameters with observations of soil moisture contents (or other related quantities) distributed over a certain period of time. The former may be of more interest for numerical weather prediction studies, whereas the latter may be more valuable for longer time integration of climate models. Springer-Verlag/Wien, 2005 Meteorology and Atmospheric Physics Springer-Verlag 92/1-2(2006-02-01), 25-32 0177-7971 92:1-2<25 2006 92 703 https://doi.org/10.1007/s00703-005-0150-y text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00703-005-0150-y text/html Onlinezugriff via DOI NATIONALLICENCE 100 1- Ren D. School of Meteorology, University of Oklahoma, Norman, Oklahoma, USA aut NATIONALLICENCE 773 0- Meteorology and Atmospheric Physics Springer-Verlag 92/1-2(2006-02-01), 25-32 0177-7971 92:1-2<25 2006 92 703 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer