Convection-permitting fully coupled WRF-Hydro ensemble simulations in high mountain environment: impact of boundary layer- and lateral flow parameterizations on land–atmosphere interactions

AbstractNumerical climate models have been upgraded by the improved description of terrestrial hydrological processes across different scales. The goal of this study is to explore the role of terrestrial hydrological processes on land–atmosphere interactions within the context of modeling uncertainties related to model physics parameterization. The models applied are the Weather Research and Forecasting (WRF) model and its coupled hydrological modeling system WRF-Hydro, which depicts the lateral terrestrial hydrological processes and further allows their feedback to the atmosphere. We conducted convection-permitting simulations (3 km) over the Heihe River Basin in Northwest China for the period 2008–2010, and particularly focused on its upper reach area of complex high mountains. In order to account for the modeling uncertainties associated with model physics parameterization, an ensemble of simulations is generated by varying the planetary boundary layer (PBL) schemes. We embedded the fully three-dimensional atmospheric water tagging method in both WRF and WRF-Hydro for quantifying the strength of land–atmosphere interactions. The impact of PBL parameterization on land–atmosphere interactions is evaluated through its direct effect on vertical mixing. Results suggest that enabled lateral terrestrial flow in WRF-Hydro distinctly increases soil moisture and evapotranspiration near the surface in the high mountains, thereby modifies the atmospheric condition regardless of the applied PBL scheme. The local precipitation recycling ratio in the study area increases from 1.52 to 1.9% due to the description of lateral terrestrial flow, and such positive feedback processes are irrespective of the modeling variability caused by PBL parameterizations. This study highlights the non-negligible contribution of lateral terrestrial flow to local precipitation recycling, indicating the potential of the fully coupled modeling in land–atmosphere interactions research.

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High-resolution fully-coupled atmospheric–hydrological modeling: a cross-compartment regional water and energy cycle evaluation

10.5194/egusphere-egu2020-17855 ◽

2020 ◽

Author(s):

Benjamin Fersch ◽

Alfonso Senatore ◽

Bianca Adler ◽

Joël Arnault ◽

Matthias Mauder ◽

...

Keyword(s):

Boundary Layer ◽

Land Surface ◽

Hydrological Modeling ◽

Weather Prediction ◽

Surface Model ◽

Near Surface ◽

Ground Heat Flux ◽

The Impact ◽

Fully Coupled ◽

Regional Water

The land surface and the atmospheric boundary layer are closely intertwined with respect to the exchange of water, trace gases and energy. Nonlinear feedback and scale dependent mechanisms are obvious by observations and theories. Modeling instead is often narrowed to single compartments of the terrestrial system or bound to traditional viewpoints of definite scientific disciplines. Coupled terrestrial hydrometeorological modeling systems attempt to overcome these limitations to achieve a better integration of the processes relevant for regional climate studies and local area weather prediction. We examine the ability of the hydrologically enhanced version of the Weather Research and Forecasting Model (WRF-Hydro) to reproduce the regional water cycle by means of a two-way coupled approach and assess the impact of hydrological coupling with respect to a traditional regional atmospheric model setting. It includes the observation-based calibration of the hydrological model component (offline WRF-Hydro) and a comparison of the classic WRF and the fully coupled WRF-Hydro models both with identical calibrated parameter settings for the land surface model (Noah-MP). The simulations are evaluated based on extensive observations at the pre-Alpine Terrestrial Environmental Observatory (TERENO Pre-Alpine) for the Ammer (600 km&#178;) and Rott (55 km&#178;) river catchments in southern Germany, covering a five month period (Jun&#8211;Oct 2016).The sensitivity of 7 land surface parameters is tested using the Latin-Hypercube One-factor-At-a-Time (LH-OAT) method and 6 sensitive parameters are subsequently optimized for 6 different subcatchments, using the Model-Independent Parameter Estimation and Uncertainty Analysis software (PEST).The calibration of the offline WRF-Hydro leads to Nash-Sutcliffe efficiencies between 0.56 and 0.64 and volumetric efficiencies between 0.46 and 0.81 for the six subcatchments. The comparison of classic WRF and fully coupled WRF-Hydro shows only tiny alterations for radiation and precipitation but considerable changes for moisture- and energy fluxes. By comparison with TERENO Pre-Alpine observations, the fully coupled model slightly outperforms the classic WRF with respect to evapotranspiration, sensible and ground heat flux, near surface mixing ratio, temperature, and boundary layer profiles of air temperature. The subcatchment-based water budgets show uniformly directed variations for evapotranspiration, infiltration excess and percolation whereas soil moisture and precipitation change randomly.

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High-resolution fully-coupled atmospheric–hydrological modeling: a cross-compartment regional water and energy cycle evaluation

10.5194/hess-2019-478 ◽

2019 ◽

Cited By ~ 1

Author(s):

Benjamin Fersch ◽

Alfonso Senatore ◽

Bianca Adler ◽

Joël Arnault ◽

Matthias Mauder ◽

...

Keyword(s):

Boundary Layer ◽

Land Surface ◽

Hydrological Modeling ◽

Weather Prediction ◽

Surface Model ◽

Near Surface ◽

Ground Heat Flux ◽

The Impact ◽

Fully Coupled ◽

Regional Water

Abstract. The land surface and the atmospheric boundary layer are closely intertwined with respect to the exchange of water, trace gases and energy. Nonlinear feedback and scale dependent mechanisms are obvious by observations and theories. Modeling instead is often narrowed to single compartments of the terrestrial system or largely bound to traditional disciplines. Coupled terrestrial hydrometeorological modeling systems attempt to overcome these limitations to achieve a better integration of the processes relevant for regional climate studies and local area weather prediction. This study examines the ability of the hydrologically enhanced version of the Weather Research and Forecasting Model (WRF-Hydro) to reproduce the regional water cycle by means of a two-way coupled approach and assesses the impact of hydrological coupling with respect to a traditional regional atmospheric model setting. It includes the observation-based calibration of the hydrological model component (offline WRF-Hydro) and a comparison of the classic WRF and the fully coupled WRF-Hydro models both with identical calibrated parameter settings for the land surface model (Noah-MP). The simulations are evaluated based on extensive observations at the preAlpine Terrestrial Environmental Observatory (TERENO-preAlpine) for the Ammer (600 km2) and Rott (55 km2) river catchments in southern Germany, covering a five month period (Jun–Oct 2016). The sensitivity of 7 land surface parameters is tested using the Latin-Hypercube One-factor-At-a-Time (LH-OAT) method and 6 sensitive parameters are subsequently optimized for 6 different subcatchments, using the Model-Independent Parameter Estimation and Uncertainty Analysis software (PEST). The calibration of the offline WRF-Hydro gives Nash-Sutcliffe efficiencies between 0.56 and 0.64 and volumetric efficiencies between 0.46 and 0.81 for the six subcatchments. The comparison of classic WRF and fully coupled WRF-Hydro, both using the calibrated parameters from the offline model, shows nominal alterations for radiation and precipitation but considerable changes for moisture- and heat fluxes. By comparison with TERENO-preAlpine observations, the fully coupled model slightly outperforms the classic WRF with respect to evapotranspiration, sensible and ground heat flux, near surface mixing ratio, temperature, and boundary layer profiles of air temperature. The subcatchment-based water budgets show uniformly directed variations for evapotranspiration, infiltration excess and percolation whereas soil moisture and precipitation change randomly.

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High-resolution fully coupled atmospheric–hydrological modeling: a cross-compartment regional water and energy cycle evaluation

Hydrology and Earth System Sciences ◽

10.5194/hess-24-2457-2020 ◽

2020 ◽

Vol 24 (5) ◽

pp. 2457-2481 ◽

Cited By ~ 4

Author(s):

Benjamin Fersch ◽

Alfonso Senatore ◽

Bianca Adler ◽

Joël Arnault ◽

Matthias Mauder ◽

...

Keyword(s):

Boundary Layer ◽

Land Surface ◽

Hydrological Modeling ◽

Weather Prediction ◽

Surface Model ◽

Near Surface ◽

Ground Heat Flux ◽

The Impact ◽

Fully Coupled ◽

Regional Water

Abstract. The land surface and the atmospheric boundary layer are closely intertwined with respect to the exchange of water, trace gases, and energy. Nonlinear feedback and scale-dependent mechanisms are obvious by observations and theories. Modeling instead is often narrowed to single compartments of the terrestrial system or bound to traditional viewpoints of definite scientific disciplines. Coupled terrestrial hydrometeorological modeling systems attempt to overcome these limitations to achieve a better integration of the processes relevant for regional climate studies and local-area weather prediction. This study examines the ability of the hydrologically enhanced version of the Weather Research and Forecasting model (WRF-Hydro) to reproduce the regional water cycle by means of a two-way coupled approach and assesses the impact of hydrological coupling with respect to a traditional regional atmospheric model setting. It includes the observation-based calibration of the hydrological model component (offline WRF-Hydro) and a comparison of the classic WRF and the fully coupled WRF-Hydro models both with identically calibrated parameter settings for the land surface model (Noah-Multiparametrization; Noah-MP). The simulations are evaluated based on extensive observations at the Terrestrial Environmental Observatories (TERENO) Pre-Alpine Observatory for the Ammer (600 km2) and Rott (55 km2) river catchments in southern Germany, covering a 5-month period (June–October 2016). The sensitivity of seven land surface parameters is tested using the Latin-Hypercube–One-factor-At-a-Time (LH-OAT) method, and six sensitive parameters are subsequently optimized for six different subcatchments, using the model-independent Parameter Estimation and Uncertainty Analysis software (PEST). The calibration of the offline WRF-Hydro gives Nash–Sutcliffe efficiencies between 0.56 and 0.64 and volumetric efficiencies between 0.46 and 0.81 for the six subcatchments. The comparison of the classic WRF and fully coupled WRF-Hydro models, both using the calibrated parameters from the offline model, shows only tiny alterations for radiation and precipitation but considerable changes for moisture and heat fluxes. By comparison with TERENO Pre-Alpine Observatory measurements, the fully coupled model slightly outperforms the classic WRF model with respect to evapotranspiration, sensible and ground heat flux, the near-surface mixing ratio, temperature, and boundary layer profiles of air temperature. The subcatchment-based water budgets show uniformly directed variations for evapotranspiration, infiltration excess and percolation, whereas soil moisture and precipitation change randomly.

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The Karakoram Highway: The Impact of Road Construction on Mountain Societies

Modern Asian Studies ◽

10.1017/s0026749x00010817 ◽

1991 ◽

Vol 25 (4) ◽

pp. 711-736 ◽

Cited By ~ 41

Author(s):

Hermann Kreutzmann

Keyword(s):

Communication Systems ◽

Road Construction ◽

Water Level Fluctuations ◽

High Mountain ◽

Functional Communication ◽

High Mountains ◽

Trade Routes ◽

Karakoram Highway ◽

The Impact ◽

Opening Up

The opening up of regions in the high mountains for motorized traffic has led world-wide to consequences concerning the penetration of these formerly remote areas.Not only have running-times and means of transport been reduced through the modern routes, but also radical developments in the mountains have been induced. In this context physio-geographical and socio-political frame conditions are of predominant importance for the installation of functional communication systems. Especially in the high mountain regions of Asia relief, snow-covers in passes, glacial movements, earthquakes, water level fluctuations of rivers at fords and limited possibilities of fuel, fodder and foodstuff supplies all restrict the chances for the development of major trade routes.

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Analyzing Spatio-Temporal Hydrological Processes and Related Gradients to Improve Hydrological Modeling in High Mountains

Landform - Structure, Evolution, Process Control - Lecture Notes in Earth Sciences ◽

10.1007/978-3-540-75761-0_15 ◽

2009 ◽

pp. 243-256

Author(s):

Ole Rößler ◽

Jörg Löffler

Keyword(s):

Hydrological Modeling ◽

Hydrological Processes ◽

High Mountains ◽

Spatio Temporal

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Focus on Thermokarst Lakes in Indian Himalaya: Inception and Implication under Warming Climate

Journal of Climate Change ◽

10.3233/jcc200012 ◽

2020 ◽

Vol 6 (2) ◽

pp. 59-69

Author(s):

Pratima Pandey ◽

S. Nawaz Ali ◽

Vikram Sharma ◽

Prashant K. Champati Ray

Keyword(s):

Western Himalaya ◽

High Mountain ◽

Thermokarst Lakes ◽

Glacial Environments ◽

Global Warming Scenario ◽

Scientific Attention ◽

Topographic Depressions ◽

Permafrost Thawing ◽

The Impact ◽

Thaw Lakes

Thermokarst (Thaw) lakes are landforms found in topographic depressions created by thawing ground ice in permafrost zones. They play an important role in the regulation of climatic functions. These lakes are a manifestation of warming surface temperatures that accelerates the ice-rich permafrost to degrade by creating marshy hollows/ponds. In the current global warming scenario, the thermokarst lakes in the high mountain regions (Himalaya) are expected to grow further. This accelerate permafrost thawing which will affect the carbon cycle, hydrology and local ecosystems. This phenomenon has attracted huge scientific attention because it has led to a rapid mass change of glaciers in the region, including extensive changes occurring on peri-glacial environments. The most striking fact is the release of an enormous amount of greenhouse gases, including methane, carbon dioxide and nitrous oxide that is locked in these lakes. The present study delves into the thermokarst lakes in the upper reaches of Chandra Valley and Western Himalaya. The study also aims at designating the impact of their changes on the ecosystem, particularly their influence on the atmospheric greenhouse gas concentrations.

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An Exploratory Study of the Online Learning Environment

Issues in Accounting Education ◽

10.2308/iace-50614 ◽

2013 ◽

Vol 29 (1) ◽

pp. 117-147 ◽

Cited By ~ 11

Author(s):

Cynthia J. Khanlarian ◽

Rahul Singh

Keyword(s):

Learning Environment ◽

Student Performance ◽

It Use ◽

Environment Impact ◽

Web Based ◽

Improve Student Performance ◽

Research Questions ◽

The Impact ◽

Relevant Factors ◽

Significant Factors

ABSTRACT Web-based homework (WBH) is an increasingly important phenomenon. There is little research about its character, the nature of its impact on student performance, and how that impact evolves over an academic term. The primary research questions addressed in this study are: What relevant factors in a WBH learning environment impact students' performance? And how does the impact of these factors change over the course of an academic term? This paper examines and identifies significant factors in a WBH learning environment and how they impact student performance. We studied over 300 students using WBH extensively for their coursework, throughout a semester in an undergraduate class at a large public university. In this paper, we present factors in the WBH learning environment that were found to have a significant impact on student performance during the course of a semester. In addition to individual and technological factors, this study presents findings that demonstrate that frustration with IT use is a component of the learning environment, and as a construct, has a larger impact than usefulness on student performance at the end of a course. Our results indicate that educators may benefit from training students and engaging them in utility of co-operative learning assignments to mitigate the level of frustration with the software in the WBH learning environment and improve student performance.

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India’s Commitments to Increase Tree and Forest Cover: Consequences for Water Supply and Agriculture Production within the Central Indian Highlands

Water ◽

10.3390/w13070959 ◽

2021 ◽

Vol 13 (7) ◽

pp. 959

Author(s):

Benjamin Clark ◽

Ruth DeFries ◽

Jagdish Krishnaswamy

Keyword(s):

Groundwater Recharge ◽

Forest Cover ◽

Hydrological Modeling ◽

Monsoon Season ◽

Forest Policy ◽

Central India ◽

Field Measurements ◽

Tree Cover ◽

Policy Goals ◽

The Impact

As part of its nationally determined contributions as well as national forest policy goals, India plans to boost tree cover to 33% of its land area. Land currently under other uses will require tree-plantations or reforestation to achieve this goal. This paper examines the effects of converting cropland to tree or forest cover in the Central India Highlands (CIH). The paper examines the impact of increased forest cover on groundwater infiltration and recharge, which are essential for sustainable Rabi (winter, non-monsoon) season irrigation and agricultural production. Field measurements of saturated hydraulic conductivity (Kfs) linked to hydrological modeling estimate increased forest cover impact on the CIH hydrology. Kfs tests in 118 sites demonstrate a significant land cover effect, with forest cover having a higher Kfs of 20.2 mm hr−1 than croplands (6.7mm hr−1). The spatial processes in hydrology (SPHY) model simulated forest cover from 2% to 75% and showed that each basin reacts differently, depending on the amount of agriculture under paddy. Paddy agriculture can compensate for low infiltration through increased depression storage, allowing for continuous infiltration and groundwater recharge. Expanding forest cover to 33% in the CIH would reduce groundwater recharge by 7.94 mm (−1%) when converting the average cropland and increase it by 15.38 mm (3%) if reforestation is conducted on non-paddy agriculture. Intermediate forest cover shows however shows potential for increase in net benefits.

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