Remote Sensing Of Total Water Storage Variability During Extreme Heat Waves

Droughts and heat waves are a major hazard for food & water security, economic development, and human & ecosystem health, among others. Over the last decade, short-term but exceptional heat waves have been observed across different regions of the world, with several locations experiencing all-time maximum temperature records. While many studies have suggested that the extreme intensity of such recent events can be attributed to a changing climate, little attention has been given to the impacts on the terrestrial water balance. This work analyzes the sensitivity of total water storage to extreme heat waves since 2003 in Europe (2003), Russia, Sahel and Middle East (2010), UK (2011), USA (2012), Australia (2013). The main objectives are to: (1) explore the relationships between temperature, precipitation and total water storage variability (2) infer the response time of extreme dry spells to total water storage decline. The methodology used in this study was based on remote sensing tools such as the GRACE mission and data assimilation from land surface models. The analysis shows recurrent annual hysteresis loops in the monthly time series of climate and water storage, which imply a time lag between the occurrence of heat waves and the depletion of soil moisture and aquifer storage. Finally, the results offer the potential to provide first-order estimates of total water storage variations for large river basins and aquifers due to climate extremes

Uncertainty Propagation In A Hydro-Meteorological Approach: From The Cloud To The Flood Map.

Globally, it is widely known that floods remain the most frequent and devastating natural hazards. Likewise, there is recent evidence showing an increase in the number of extreme flood events observed around the world. Therefore, it is imperative to develop an integrated flood assessment framework that enables a better understanding of both, the generation of these events and the interaction of key variables within the hydro-meteorological system. The aim of this investigation is to study the propagation of meteorological uncertainty to a numerically estimated flood map. For such purpose, we utilise a cascade modelling approach comprised by a Numerical Weather Prediction Model (NWP), a rainfall-runoff model and a standard 2D hydrodynamic model. Uncertainty is considered in the meteorological model (Weather Research and Forecasting model) using a multi-physics ensemble technique considering twenty four parameterization schemes. The resulting precipitation fields are used as input in a distributed hydrological model to generate spaghetti plots, which are then employed as forcing in a 2D hydrodynamic model. The approach is utilised for the reproduction of an extreme flood event in southern Mexico, for which field data (rain gauges) and satellite imagery are available. Although there are more uncertainties involved in the determination of a flooded area, the methodology represents a robust approach to acknowledge the propagation from the meteorological model to the flood map. Thus, it favours preventive action in the generation of better flood management strategies

Water Supply Source Evaluation in Unmanaged Aquifer Recharge Zones: The Mezquital Valley (Mexico) Case Study

The Mezquital Valley (MV) hosts the largest unmanaged aquifer recharge scheme in the world. The metropolitan area of Mexico City discharges ~60 m3/s of raw wastewater into the valley, a substantial share of which infiltrates into the regional aquifer. In this work, we aim to develop a comprehensive approach, adapted from oil and gas reservoir modeling frameworks, to assess water supply sources located downgradient from unmanaged aquifer recharge zones. The methodology is demonstrated through its application to the Mezquital Valley region. Geological, geoelectrical, petrophysical and hydraulic information is combined into a 3D subsurface model and used to evaluate downgradient supply sources. Although hydrogeochemical variables are yet to be assessed, outcomes suggest that the newly-found groundwater sources may provide a long-term solution for water supply. Piezometric analyses based on 25-year records suggest that the MV is close to steady-state conditions. Thus, unmanaged recharge seems to have been regulating the groundwater balance for the last decades. The transition from unmanaged to managed recharge is expected to provide benefits to the MV inhabitants. It will also be likely to generate new uncertainties in relation to aquifer dynamics and downgradient systems

Binational reflections on pathways to groundwater security in the Mexico–United States borderlands

Shared groundwater resources between Mexico and the United States are facing unprecedented stressors. We reflect on how to improve water security for groundwater systems in the border region. Our reflection begins with the state of groundwater knowledge, and the challenges groundwater resources face from a physical, societal and institutional perspective. We conclude that the extent of ongoing cooperation frameworks, joint and remaining research efforts, from which alternative strategies can emerge, still need to be developed. The way forward offers a variety of cooperation models as the future offers rather complex, shared and multidisciplinary water challenges to the Mexico–US borderlands

Frecuencia de valores extremos en hidrología

El propósito fundamental que persigue el presente texto es orientar e introducir tanto a ingenieros hidrólogos como a profesionales de las ciencias naturales, en el conocimiento de los fundamentos, principios y aplicacionesdel análisis de frecuencia de valores extremos de eventos hidrológicos. Por su parte, el objetivo básico del análisis de frecuencia de valores extremos se ha enfocado a estimar la probabilidad de ocurrencia de eventos hidrológicos asociados con valores máximos anuales, valores mínimos anuales y valores máximos anuales integrados por dos poblaciones, a partir de La técnica matemática de las funciones de distribución de probabilidad. Ahora bien, para desarrollar el análisis de frecuencia de eventos extremos de tipo hidrológico, que ocurren en diferentes cuencas hidrológicas de nuestro país, este documento se ha estructurado en cinco capítulos donde se incluyen en forma detallada el desarrollo histórico, los fundamentos y principios y aplicaciones con datos reales

A satellite-based terrestrial water storage indicator to assess the severity of a heatwave

No abstract available

Sensitivity of a data-driven soil water balance model to estimate summer evapotranspiration along a forest chronosequence

The hydrology of ecosystem succession gives rise to new challenges for the analysis and modelling of water balance components. Recent large-scale alterations of forest cover across the globe suggest that a significant portion of new biophysical environments will influence the long-term dynamics and limits of water fluxes compared to pre-succession conditions. This study assesses the estimation of summer evapotranspiration along three FLUXNET sites at Campbell River, British Columbia, Canada using a data-driven soil water balance model validated by Eddy Covariance measurements. It explores the sensitivity of the model to different forest succession states, a wide range of computational time steps, rooting depths, and canopy interception capacity values. Uncertainty in the measured EC fluxes resulting in an energy imbalance was consistent with previous studies and does not affect the validation of the model. The agreement between observations and model estimates proves that the usefulness of the method to predict summer AET over mid- and long-term periods is independent of stand age. However, an optimal combination of the parameters rooting depth, time step and interception capacity threshold is needed to avoid an underestimation of AET as seen in past studies. The study suggests that summer AET could be estimated and monitored in many more places than those equipped with Eddy Covariance or sap-flow measurements to advance the understanding of water balance changes in different successional ecosystems

On the connection between terrestrial and riparian vegetation: the role of storage partitioning in water-limited catchments

Predictability of hydrological response in dryland environments: a comparative study across North America project; University of Arizona; CONACYT12 month embargo; Version of record online: 6 December 2016This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]