Do land models miss key soil hydrological processes controlling soil moisture memory?

<p>Soil moisture memory (SMM), which refers to how long a perturbation in soil moisture (SM) can last, is critical for understanding climatic, hydrological, and ecosystem interactions. Most land surface models (LSMs) tend to overestimate surface soil moisture and its persistency (or SMM), sust...

Full description

Saved in:
Bibliographic Details
Main Authors: M. A. Farmani, A. Behrangi, A. Gupta, A. Tavakoly, M. Geheran, G.-Y. Niu
Format: Article
Language:English
Published: Copernicus Publications 2025-01-01
Series:Hydrology and Earth System Sciences
Online Access:https://hess.copernicus.org/articles/29/547/2025/hess-29-547-2025.pdf
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1832582792383299584
author M. A. Farmani
A. Behrangi
A. Behrangi
A. Gupta
A. Tavakoly
A. Tavakoly
M. Geheran
G.-Y. Niu
author_facet M. A. Farmani
A. Behrangi
A. Behrangi
A. Gupta
A. Tavakoly
A. Tavakoly
M. Geheran
G.-Y. Niu
author_sort M. A. Farmani
collection DOAJ
description <p>Soil moisture memory (SMM), which refers to how long a perturbation in soil moisture (SM) can last, is critical for understanding climatic, hydrological, and ecosystem interactions. Most land surface models (LSMs) tend to overestimate surface soil moisture and its persistency (or SMM), sustaining spuriously large soil surface evaporation during dry-down periods. We attempt to answer a question: do LSMs miss or misrepresent key hydrological processes controlling SMM? We use a version of Noah-MP with advanced hydrology that explicitly represents preferential flow and surface ponding and provides optional schemes of soil hydraulics. We test the effects of these processes, which are generally missed by most LSMs in SMM. We compare SMMs computed from various Noah-MP configurations against that derived from the Soil Moisture Active Passive (SMAP) L3 soil moisture and in situ measurements from the International Soil Moisture Network (ISMN) from the years 2015 to 2019 over the contiguous United States (CONUS). The results suggest that (1) soil hydraulics plays a dominant role and the Van Genuchten hydraulic scheme reduces the overestimation of the long-term surface SMM produced by the Brooks–Corey scheme, which is commonly used in LSMs; (2) explicitly representing surface ponding enhances SMM for both the surface layer and the root zone; and (3) representing preferential flow improves the overall representation of soil moisture dynamics. The combination of these missing schemes can significantly improve the long-term memory overestimation and short-term memory underestimation issues in LSMs. We suggest that LSMs for use in seasonal-to-subseasonal climate prediction should, at least, adopt the Van Genuchten hydraulic scheme.</p>
format Article
id doaj-art-ee0fd7c6d9b94adaa105de2104f35d26
institution Kabale University
issn 1027-5606
1607-7938
language English
publishDate 2025-01-01
publisher Copernicus Publications
record_format Article
series Hydrology and Earth System Sciences
spelling doaj-art-ee0fd7c6d9b94adaa105de2104f35d262025-01-29T09:24:08ZengCopernicus PublicationsHydrology and Earth System Sciences1027-56061607-79382025-01-012954756610.5194/hess-29-547-2025Do land models miss key soil hydrological processes controlling soil moisture memory?M. A. Farmani0A. Behrangi1A. Behrangi2A. Gupta3A. Tavakoly4A. Tavakoly5M. Geheran6G.-Y. Niu7Department of Hydrology and Atmospheric Sciences, University of Arizona, Tucson, AZ, USADepartment of Hydrology and Atmospheric Sciences, University of Arizona, Tucson, AZ, USADepartment of Geosciences, University of Arizona, Tucson, AZ, USADepartment of Hydrology and Atmospheric Sciences, University of Arizona, Tucson, AZ, USAUS Army Engineer Research and Development Center, Coastal and Hydraulics Laboratory, Vicksburg, MS, USAEarth System Science Interdisciplinary Center, University of Maryland, College Park, MD, USAUS Army Engineer Research and Development Center, Coastal and Hydraulics Laboratory, Vicksburg, MS, USADepartment of Hydrology and Atmospheric Sciences, University of Arizona, Tucson, AZ, USA<p>Soil moisture memory (SMM), which refers to how long a perturbation in soil moisture (SM) can last, is critical for understanding climatic, hydrological, and ecosystem interactions. Most land surface models (LSMs) tend to overestimate surface soil moisture and its persistency (or SMM), sustaining spuriously large soil surface evaporation during dry-down periods. We attempt to answer a question: do LSMs miss or misrepresent key hydrological processes controlling SMM? We use a version of Noah-MP with advanced hydrology that explicitly represents preferential flow and surface ponding and provides optional schemes of soil hydraulics. We test the effects of these processes, which are generally missed by most LSMs in SMM. We compare SMMs computed from various Noah-MP configurations against that derived from the Soil Moisture Active Passive (SMAP) L3 soil moisture and in situ measurements from the International Soil Moisture Network (ISMN) from the years 2015 to 2019 over the contiguous United States (CONUS). The results suggest that (1) soil hydraulics plays a dominant role and the Van Genuchten hydraulic scheme reduces the overestimation of the long-term surface SMM produced by the Brooks–Corey scheme, which is commonly used in LSMs; (2) explicitly representing surface ponding enhances SMM for both the surface layer and the root zone; and (3) representing preferential flow improves the overall representation of soil moisture dynamics. The combination of these missing schemes can significantly improve the long-term memory overestimation and short-term memory underestimation issues in LSMs. We suggest that LSMs for use in seasonal-to-subseasonal climate prediction should, at least, adopt the Van Genuchten hydraulic scheme.</p>https://hess.copernicus.org/articles/29/547/2025/hess-29-547-2025.pdf
spellingShingle M. A. Farmani
A. Behrangi
A. Behrangi
A. Gupta
A. Tavakoly
A. Tavakoly
M. Geheran
G.-Y. Niu
Do land models miss key soil hydrological processes controlling soil moisture memory?
Hydrology and Earth System Sciences
title Do land models miss key soil hydrological processes controlling soil moisture memory?
title_full Do land models miss key soil hydrological processes controlling soil moisture memory?
title_fullStr Do land models miss key soil hydrological processes controlling soil moisture memory?
title_full_unstemmed Do land models miss key soil hydrological processes controlling soil moisture memory?
title_short Do land models miss key soil hydrological processes controlling soil moisture memory?
title_sort do land models miss key soil hydrological processes controlling soil moisture memory
url https://hess.copernicus.org/articles/29/547/2025/hess-29-547-2025.pdf
work_keys_str_mv AT mafarmani dolandmodelsmisskeysoilhydrologicalprocessescontrollingsoilmoisturememory
AT abehrangi dolandmodelsmisskeysoilhydrologicalprocessescontrollingsoilmoisturememory
AT abehrangi dolandmodelsmisskeysoilhydrologicalprocessescontrollingsoilmoisturememory
AT agupta dolandmodelsmisskeysoilhydrologicalprocessescontrollingsoilmoisturememory
AT atavakoly dolandmodelsmisskeysoilhydrologicalprocessescontrollingsoilmoisturememory
AT atavakoly dolandmodelsmisskeysoilhydrologicalprocessescontrollingsoilmoisturememory
AT mgeheran dolandmodelsmisskeysoilhydrologicalprocessescontrollingsoilmoisturememory
AT gyniu dolandmodelsmisskeysoilhydrologicalprocessescontrollingsoilmoisturememory