Using the maximum entropy production approach to integrate energy budget modelling in a hydrological model
<p>Total terrestrial evaporation, also referred to as evapotranspiration, is a key process for understanding the hydrological impacts of climate change given that warmer surface temperatures translate into an increase in the atmospheric evaporative demand. To simulate this flux, many hydrologi...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2019-09-01
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| Series: | Hydrology and Earth System Sciences |
| Online Access: | https://www.hydrol-earth-syst-sci.net/23/3843/2019/hess-23-3843-2019.pdf |
| Summary: | <p>Total terrestrial evaporation, also referred to as evapotranspiration, is a key process for
understanding the hydrological impacts of climate change given that warmer
surface temperatures translate into an increase in the atmospheric
evaporative demand. To simulate this flux, many hydrological models rely on
the concept of potential evaporation (PET), although large differences have
been observed in the response of PET models to climate change. The maximum entropy production (MEP) model of land surface fluxes offers an alternative
approach for simulating terrestrial evaporation in a simple way while
fulfilling the physical constraint of energy budget closure and providing a
distinct estimation of evaporation and transpiration. The objective of this
work is to use the MEP model to integrate energy budget modelling within a
hydrological model. We coupled the MEP model with HydroGeoSphere (HGS), an
integrated surface and subsurface hydrologic model. As a proof of concept,
we performed one-dimensional soil column simulations at three sites of the
AmeriFlux network. The coupled model (HGS-MEP) produced realistic simulations
of soil water content (root-mean-square error – RMSE – between 0.03 and 0.05 m<span class="inline-formula"><sup>3</sup></span> m<span class="inline-formula"><sup>−3</sup></span>; NSE – Nash–Sutcliffe efficiency –
between 0.30 and 0.92) and terrestrial evaporation (RMSE between 0.31 and
0.71 mm d<span class="inline-formula"><sup>−1</sup></span>; NSE between 0.65 and 0.88) under semi-arid, Mediterranean
and temperate climates. At the daily timescale, HGS-MEP outperformed the
stand-alone HGS model where total terrestrial evaporation is derived from
potential evaporation, which we computed using the Penman–Monteith equation,
although both models had comparable performance at the half-hourly timescale. This research demonstrated the potential of the MEP model to improve
the simulation of total terrestrial evaporation in hydrological models,
including for hydrological projections under climate change.</p> |
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| ISSN: | 1027-5606 1607-7938 |