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Item type:Publication, Access status: without files , Toward prediction of land subsidence assisted by artificial intelligence approaches(Copernicus Publications, 2023-05-15); 13 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , Modes of interaction and varying feedback between groundwater and climate depending on soil characteristicsClimate, climate variability, and climate change could influence groundwater. Shifts in precipitation patterns, recharge, or snowmelt are among the several climate-related variables with important impacts on groundwater. However, the climate-groundwater relationship is not one-way. Groundwater can also impact the climate itself via its influence on different processes and variables such as evaporation, soil moisture, and vegetation. Understanding the interactions and the feedback relationship between groundwater and climate is crucial for sustainable water resource management and resilient adaptation to climate change. Current understanding of how climate influences groundwater and the resulting feedback from groundwater and its impacts on climate is limited. This is of particular importance in the face of projected climatic changes. Here, we aim to develop a simple analytical framework to extend the projection capabilities required to characterize the climate-groundwater interactions depending on the soil characteristics serving as an intermediate domain between the groundwater and climate systems. Our proposed analytical framework can be used to identify potential regions with significant two-way (bidirectional) interactions between climate and groundwater using soil characteristics and soil water retention curves following the theoretical lines discussed in Shokri and Salvucci (2011) and Or and Lehmann (2019). Using this framework, we identify regions of expected hydraulic connections between groundwater and soil surface, depending on the competition between capillary forces and the limiting gravity and viscous forces, and the groundwater depth (GWD) in the city of Hamburg. We argue that in regions with bidirectional interactions, groundwater is potentially more vulnerable to climate change and variability. Moreover, our initial results suggest that regions with finer textured soils are more sensitive to changes in evaporation and air temperature in terms of hydraulic connections between groundwater and the soil surface, which can influence the groundwater-climate interactions. Our analysis provides the basis for further investigation of the feedback impacts of groundwater on several variables, such as soil moisture, ground cooling capacity, and vegetation patterns under different climate change scenarios. ReferencesOr, D., & Lehmann, P. (2019). Surface evaporative capacitance: How soil typeand rainfall characteristics affect global-scale surface evaporation. Water Resources Research, 55, 519-539.https://doi.org/10.1029/2018WR024050.Shokri, N., Salvucci, G. (2011). Evaporation from porous media in the presence of a water table. Vadose Zone J., 10, 1309-1318.Publicationtype: Conference Paper20 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , Insignificant but overlooked : evaporative losses from small reservoirs in southern Europe(Copernicus Publications, 2023-05-15); ; The application of agricultural ponds and small engineered impoundments (often < 0.1 km2 area) is growing globally to support livestock, irrigation, and local municipal and industrial demands during dry spells. However, evaporation diminishes the storage efficiency of these popular but often un-inventoried resources. This study provides a reliable framework for estimating global abundance of small reservoirs and associated evaporative hotspots under different climate change scenarios serving as a basis for future water management and planning. To show the applicability of the proposed method and the utility of the insights it provides, we use satellite data to identify spatio-temporal distribution of small reservoirs (~0.001 to 0.1 km2 area) in southern Europe (Italy, Spain, and Portugal) where irrigation heavily depends on water storage in agricultural ponds. While current estimates of evaporative water losses from small reservoirs often rely on pan measurements or Penman-type approaches with locally calibrated heat and mass transfer coefficients, we employ a physically-based model [Aminzadeh et al., 2018] that accounts for inherent reservoir characteristics (e.g., depth and light attenuation), and radiative energy storage within the water body to quantify energy balance and evaporation dynamics from small water reservoirs. Our preliminary results indicate that cumulative area of small reservoirs in the study area has increased from 518 km2 in 2000 to 614 km2 in 2020 (18.5% increase) with cumulative evaporative losses that may exceed 400 Mm3 during warm months (April to September). Although the estimated evaporative water loss looks negligible relative to the annual agricultural water use (< 2%), its significance could be gauged by societal impacts in these regions with chronic water stress problems or the cost of alternate water sources (e.g., desalinated water).Publicationtype: Conference Paper26 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , Global scale estimation of evaporative losses from large lakes located in different climatic zones(European Geosciences Union, 2023-04); ; ; Reliable projection of evaporative fluxes from lakes is at the core of a wide range of hydrological, climatological, and environmental modeling processes. Evaporation results in losses of blue water from lakes in regions with limited freshwater resources and affects aquatic and terrestrial biodiversity. While current estimates of evaporative losses from lakes remain largely empirical depending on locally calibrated heat and mass transfer coefficients or remotely sensed surface temperature data, we propose a physically-based framework that builds on inherent lake characteristics (e.g., bathymetry, light attenuation characteristics) and atmospheric forcing variables to quantify energy dynamics of the water body and surface evaporative fluxes from the largest lakes across different climatic zones on a global scale. To evaluate the performance of the model, the modelling results determining the seasonal variation of vertical temperature profiles and latent heat loss were compared with in situ measurements of water temperature and surface heat fluxes measured in Lake Mead, in the Southwestern USA. We found good agreements between the physically-based estimations and the measured data. We then quantified evaporative losses from 30 lakes in 30 different climate zone sub-types with an average depth ranging from 1.1 m to 577 m and a surface area of 45 km² to 82,000 km². Our preliminary findings for 2020 indicate that variation of first-order atmospheric parameters (i.e., wind, radiation, air temperature, and humidity) across climatic zones and the change in lake bathymetry altering local vertical temperature profiles within the water body significantly affect evaporative losses. The energy-constrained model enables quantifying the extent of evaporative water losses from lakes and provides a theoretical basis for delineating potential impacts on water management and ecological and climatological processes under different climate change scenarios.Publicationtype: Conference Poster24 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Impact of soil texture and heterogeneity on complex interactions between surface soil salinity and saltwater intrusion in coastal regions(Copernicus Publications, 2023-05-15); ; ; Soil salinization, referring to the excessive accumulation of soluble salts in soil to a degree that adversely influences vegetation and environmental health, is an unfolding challenge threatening soil health, vegetation and consequently food security with serious socio-economics implications (Hassani et al., 2020, 2021). High salinities in the root zone reduce water and nutrient uptake and result in soil infertility, freshwater contamination at the surface and the loss of biodiversity.Here, we concentrate on soil salinization in coastal areas due to saltwater intrusion and the groundwater salinization, partly influenced by climate change. In low-lying coastal regions where, saline groundwater levels are shallow, saltwater intrusion poses risks to vegetation and soil health since the soluble salt could be transported toward the surface. This causes soil salinization depending on the competition between upward capillary forces and the limiting downward gravity and viscous forces. Several parameters influence such a competition including soil texture and heterogeneity. We developed a quantitative framework, using software package FEFLOW, to delineate the regional impact of soil textures and arrangements on salt transport toward the surface in low-lying coastal regions. The model includes a wide range of hydrologic, soil and climate related factors such as hydraulic heads, soil properties, and groundwater recharge. We evaluated the performance of the developed model using field data measured in the "Alte Land" located in north Germany near the Elbe estuary - an agriculturally significant low-lying region threatened by increasing soil surface salinity.The evaluation of the model against field-data was followed by conducting the simulation under several hypothetical scenarios differing in soil textures, layering and arrangements to investigate how these parameters would influence soil surface salinity driven by the saltwater intrusion in coastal areas. Our results highlight the prominent effects of different soil textures and arrangements on the regional surface soil salinity and the amount of salt deposited close to the surface. This agrees with the conclusions of laboratory experiments which were conducted in other studies at scales much smaller than the one investigated in our analysis (Shokri-Kuehni et al., 2020). Our results suggest that an effective soil remediation strategy for salinity treatment would require high resolution 3D mapping of soil properties which influences soil salinization. Our findings shed new light on the dominant parameters influencing surface soil salinity in coastal areas threatened by the saltwater intrusion as a result of the projected climate changes.Publicationtype: Conference Paper22 191