Systemic risk and compound vulnerability impact pathways of food insecurity in Somalia

In a strongly interconnected world, extreme and compound events pose systemic risks to food security and populations already vulnerable to the impacts of climate change. Pre-existing vulnerabilities can also compound, interfering with adaptation strategies and affecting human migration patterns. While some drivers of compound vulnerability are known on a normative level, there remains a critical gap on the relationship between drivers of vulnerability systemic risk, and food insecurity outcomes. We use a systemic risk impact pathway (SRIP) model to gain data-driven insights on the drivers of systemic risk and the impacts on food insecurity in Somalia. By applying data on extreme weather and food insecure internally displaced populations from 2011 to 2019 we isolate different components of vulnerability and show how they compound and relate to systemic risk drivers. Our findings contribute to the empirical evidence on limits to adaptation indicating that systemic risk impacts compound vulnerabilities and act as adaptation ‘roadblocks’ for food security. We argue that a systems design can provide guardrails to resilience opportunities where compound vulnerabilities overstretch fragile resilience levels.publishedVersio

The risk and consequences of multiple breadbasket failures: an integrated copula and multilayer agent-based modeling approach

Climate shocks to food systems have been thoroughly researched in terms of food security and supply chain management. However, sparse research exists on the dependent nature of climate shocks on food-producing breadbasket regions and their subsequent cascading impacts. In this paper, we propose that a copula approach, combined with a multilayer network and an agent-based model, can give important insights on how tail-dependent shocks can impact food systems. We show how such shocks can potentially cascade within a region through the behavioral interactions of various layers. Based on our suggested framework, we set up a model for India and show that risks due to drought events multiply if tail dependencies during extremes drought is explicitly taken into account. We further demonstrate that the risk is exacerbated if displacement also takes place. In order to quantify the spatial–temporal evolution of climate risks, we introduce a new measure of multilayer vulnerability that we term Vulnerability Rank or VRank. We find that with higher food production losses, the number of agents that are affected increases nonlinearly due to cascading effects in different network layers. These effects spread to the unaffected regions via large-scale displacement causing sudden changes in production, employment and consumption decisions. Thus, demand shifts also force supply-side adjustments of food networks in the months following the climate shock. We suggest that our framework can provide a more accurate picture of food security-related systemic risks caused by multiple breadbasket failures which, in turn, can better inform risk management and humanitarian aid strategies

Hydroeconomic analysis of droughts in the Ebro basin using copulas for streamflow simulation

Publishe

Hydroeconomic analysis of droughts in the Ebro basin using copulas for streamflow simulation

Climate change intensifies water scarcity in arid and semi-arid regions where pressures on water resources are significant, further compromising the sustainability of water systems. Climate change triggers more frequent, longer and intense droughts that bring about serious challenges for management. Hydroeconomic analysis provides a modeling framework for policy design at basin scale, taking into consideration the spatial and temporal relationships between water sectors. In this study, an integrated hydroeconomic model of the Ebro basin is used to analyze the economic impacts of climate change under several water management alternatives. An innovative approach, the Copula procedure, is used to generate longer, and more intense and frequent drought events. Several policy scenarios are simulated by combining two water allocation rules, proportional share or water markets, with the possibility of investments in advanced irrigation systems. The sustainability of the Ebro water system is evaluated by looking at its reliability, resilience and vulnerability under each policy alternative. The risk assessment of the benefit losses informs on the water system exposure to extreme drought events, and the contribution of management options in reducing potential losses. The results highlight that climate change exacerbates the likelihood of substantial economic losses from droughts, which compromise the sustainability of the water system. Water markets and irrigation efficiency enhancements reduce uncertainty and losses from droughts, although there is a trade-off between irrigation benefits and damages to aquatic ecosystems. However, the effectiveness of this policy combination decreases for longer and intense droughts.Este trabajo forma parte de los proyectos RTA2017-00082-00-00 “Sostenibilidad del Uso de la Tierra y el Agua en las Actividades Agrarias y Protección de los Ecosistemas ante las Sequías y el Cambio Climático” y RTA2014-00050-00-00 “ La Gestión del Regadío ante la Escasez de Agua, las Sequias y el Cambio Climático” financiados en parte con fondos FEDERPublishe

Water Security, Droughts and the Quantification of their Risks to Agriculture: A Global Picture in Light of Climatic Change

As a consequence of climatic change, climate variability is expected to increase and climate extremes to become more frequent. Rising water and food demand are further exacerbating the risks to global water and food security. The variability but also the spatial inter-connectedness in our globalized world make our systems more vulnerable to shocks and disasters. To sustain the global water and food security, more knowledge about risks, especially risks of simultaneous shocks is needed. This thesis maps and quantifies risks to global water and food security from a water-food-climate perspective. It starts on a global scale looking at water security in major river basins and then concentrates on major food producing regions of three important crops. The thesis explores how storage can buffer inter- and intra-regional hydrological variability. A water balance model is developed and used to find hotspots of water shortages and to identify river basins where more investment in infrastructure is needed to improve and sustain water security. Looking at food security, global wheat, maize and soybean breadbaskets are identified and used to estimate risks of simultaneous production shocks. Focusing on wheat, I apply different copula approaches to model joint risks of low yields. It is shown quantitatively that (i) it is important to include spatial dependencies in risks studies and that (ii) inter-regional risk pooling could decrease post-disaster liabilities of governments and international organizations. The last part of the thesis focuses on climate impacts on food production. Relevant climate variables for crop growth in the breadbaskets are identified and joint climate risks are estimated using regular vine copulas. It is shown that so far, only wheat has experienced an increase in simultaneous climate risks. In maize and soybean production regions, positive and negative climate risk changes are offsetting each other on a global scale. Looking at future projections, however, it is shown that under a 1.5 and 2 °C global mean warming, simultaneous climate risks increase for all three crops, especially for maize where the return periods of all five breadbaskets experiencing climate risks decrease from 16 to every second year. The findings of this thesis can inform policy makers, businesses and international organizations about risks to global water and food security resulting from climate variability and extremes. It indicates where policies and infrastructure investments are needed to maintain water security, it can assist in building inter-governmental risk pooling schemes and contribute to current climate policy discussions.</p

Water Security, Droughts and the Quantification of their Risks to Agriculture: A Global Picture in Light of Climatic Change

As a consequence of climatic change, climate variability is expected to increase and climate extremes to become more frequent. Rising water and food demand are further exacerbating the risks to global water and food security. The variability but also the spatial inter-connectedness in our globalized world make our systems more vulnerable to shocks and disasters. To sustain the global water and food security, more knowledge about risks, especially risks of simultaneous shocks is needed. This thesis maps and quantifies risks to global water and food security from a water-food-climate perspective. It starts on a global scale looking at water security in major river basins and then concentrates on major food producing regions of three important crops. The thesis explores how storage can buffer inter- and intra-regional hydrological variability. A water balance model is developed and used to find hotspots of water shortages and to identify river basins where more investment in infrastructure is needed to improve and sustain water security. Looking at food security, global wheat, maize and soybean breadbaskets are identified and used to estimate risks of simultaneous production shocks. Focusing on wheat, I apply different copula approaches to model joint risks of low yields. It is shown quantitatively that (i) it is important to include spatial dependencies in risks studies and that (ii) inter-regional risk pooling could decrease post-disaster liabilities of governments and international organizations. The last part of the thesis focuses on climate impacts on food production. Relevant climate variables for crop growth in the breadbaskets are identified and joint climate risks are estimated using regular vine copulas. It is shown that so far, only wheat has experienced an increase in simultaneous climate risks. In maize and soybean production regions, positive and negative climate risk changes are offsetting each other on a global scale. Looking at future projections, however, it is shown that under a 1.5 and 2 °C global mean warming, simultaneous climate risks increase for all three crops, especially for maize where the return periods of all five breadbaskets experiencing climate risks decrease from 16 to every second year. The findings of this thesis can inform policy makers, businesses and international organizations about risks to global water and food security resulting from climate variability and extremes. It indicates where policies and infrastructure investments are needed to maintain water security, it can assist in building inter-governmental risk pooling schemes and contribute to current climate policy discussions.</p

Weather and their effect on crop yields in Scotland 1935-2012

The purpose of this paper is to analyse the effect that weather variables have on the mean and variance of the yields of barley, oats, potatoes and wheat in Scotland, during the period 1935- 2012. Although theoretically grounded on the stochastic production function approach, the paper uses the generalised autoregressive conditional heteroskedastic (GARCH) to model the variance of the crop yields. Results indicate that temperature has a positive effect on the mean yield, whilst rainfall has a negative effect on it. In addition, both temperature and rainfall have differentiated results on the crop yields’ variances