Rootzone Soil Moisture Dynamics Using Terrestrial WaterEnergy Coupling Academic Article

abstract

• AbstractA lack of highdensity rootzone soil moisture (RZ) observations limits the estimation of continentalscale, spacetime contiguous RZ dynamics. We derive a proxy of daily RZ dynamics active rootzone degree of saturation (SRZ) by recursive lowpass (LP) filtering of surface soil moisture (S) within a terrestrial waterenergy coupling (WEC) framework. We estimate the LP filter parameters and WEC thresholds for the piecewiselinear coupling between SRZ and evaporative fraction (EF) at remote sensing and field scale over the Contiguous U.S. We use S from the Soil Moisture ActivePassive (SMAP) satellite and 218 insitu stations, with EF from the Moderate Resolution Imaging Spectroradiometer. The estimated SRZ compares well against SMAP Level4 estimates and insitu RZ, at the corresponding scale. The instantaneous hydrologic state (SRZ) visvis the WEC thresholds is proposed as a rootzone soil moisture stress index (SMSRZ) for nearrealtime operational agricultural drought monitoring and agrees well with established drought metrics.

authors

• Mohanty, Binayak

published proceedings

• Geophysical Research Letters

author list (cited authors)

• Sehgal, V., Mohanty, B. P., & Reichle, R. H.

complete list of authors

• Sehgal, Vinit||Mohanty, Binayak P||Reichle, Rolf H

publisher

• American Geophysical Union (AGU)  Publisher

published in

• Geophysical Research Letters  Journal

keywords

• 37 Earth Sciences
• 3707 Hydrology
• 40 Engineering
• 4013 Geomatic Engineering

Digital Object Identifier (DOI)

• 10.1029/2024gl110342

volume

• 51

issue

• 19