Management zones in transboundary aquifers: A review of delineation methods under a new framework of cross-border groundwater impacts

Attention on the use of transboundary aquifers (TBAs) and their cross-border impacts is growing as countries become increasingly concerned about their long-term water security. Cross-border impacts, in groundwater quality and quantity, tend to concentrate in specific parts of TBAs, as they largely depend on the transboundary flow dynamics...

Investigating sources of variability in closing the terrestrial water balance with remote sensing

Remote sensing (RS) data are becoming an increasingly important source of information for water resource management as they provide spatially distributed data on water availability and use. However, in order to guide appropriate use of the data, it is important to understand the impact of the uncertainties of RS data on water resource studies....

Uncertainty assessment of satellite remote-sensing-based evapotranspiration estimates: a systematic review of methods and gaps

Satellite remote sensing (RS) data are increasingly being used to estimate total evaporation, often referred to as evapotranspiration (ET), over large regions. Since RS-based ET (RS-ET) estimation inherits uncertainties from several sources, many available studies have assessed these uncertainties using different methods. However, the...

Towards realization of nexus-doing at the grassroots level: Water-energy-food governance assessment in the Songwe River Basin (Tanzania and Malawi)

The intricate connections between water, land, food, energy, and climate change require a multicentric approach to evaluating the trade-offs and synergies needed to achieve sustainable development. For example, the amount of water required in irrigated agriculture, consumptive water uses, and hydro-power production can potentially lead to...

An African perspective on the Water-Energy-Food nexus

There is a need to address resource security and distributional justice in developing countries. People need water, energy, and food to sustain their livelihoods, grow economies, and achieve sustainable development. The interactions between these resource sectors form the crux of water-energy-food (WEF) nexus assessments. In this study, we...

A yield gap analysis to assess vulnerability of commercial sugarcane to climatic extremes in southern Africa

Sugarcane yields have steadily declined across southern Africa for the past 25 years and, despite research into the causes, there has been limited progress in addressing these trends. This study developed a methodology of assessing yield declines and performed a yield gap analysis to assess and develop recommendations to assist in combating...

Uncertainty in Satellite Remote Sensing Derived Evapotranspiration Estimation: Current Status and Assessment Methods

Evapotranspiration (ET), a key variable in both water and energy cycles. It is very challenging to measure or estimate in large regions. Among many approaches to estimate ET indirectly (e.g. through hydrological modelling), models that are based on satellite remote sensing data (RS) are increasingly being used. However, the RS-based models...

Tools and indices for WEF nexus analysis

The water-energy-food (WEF) nexus is shown to be a highly interconnected, complex system, operating over multiple time scales, and at spatial scales from household to global. The key WEF nexus foci issues and challenges are known to be extremely diverse and change depending on the local situation and setting, the scale at which the nexus is...

Water - Energy - Food Nexus Narratives and Resource Securities: A Global South Perspective

Water-Energy-Food Nexus Narratives and Resource Securities: A Global South Perspective provides a knowledge synthesis on the water-energy-food (WEF) nexus, focusing primarily on the global south. By presenting concepts, analytical tools, and case studies, the book serves as a practical resource for researchers, policymakers, and practitioners...

Transboundary WEF nexus analysis: a case study of the Songwe River Basin

Over the past decade, the water, energy, and food (WEF) nexus approach has evolved to become a focus of the Southern African Development Community (SADC) development strategies. However, a lack of empirical evidence, appropriate methods, and qualitative and quantitative tools to implement the WEF nexus approach has been highlighted. This...

Scales of application of the WEF nexus approach

Water, energy, and food (WEF) systems form a complex interconnected network, operational at scales from the household up to the global. These scales, like the nexus sectors themselves, and mutually interconnected, with lower-level characteristics help drive higher-level resource management, and vice versa. This chapter highlights recent WEF...

Streamflow droughts aggravated by human activities despite management

Human activities both aggravate and alleviate streamflow drought. Here we show that aggravation is dominant in contrasting cases around the world analysed with a consistent methodology. Our 28 cases included different combinations of human-water interactions. We found that water abstraction aggravated all drought characteristics, with...

Emerging Themes and Future Directions of Multi-Sector Nexus Research and Implementation

Water, energy, and food are all essential components of human societies. Collectively, their respective resource systems are interconnected in what is called the “nexus”. There is growing consensus that a holistic understanding of the interdependencies and trade-offs between these sectors and other related systems is critical to solving many of...