The sustainability of groundwater resources has been a central issue in the Upper Guadiana Basin (Spain) since two of its primary aquifer units were declared overexploited at the end of the 1990s. Three hydrogeological aquifer units located to the north of the primary aquifers have rarely been studied because of their low economic value, despite a large part of the wetlands of La Mancha Húmeda Biosphere Reserve overlying the Basin. This report presents the foundations upon which conceptual and numerical models of the Upper Guadiana Basin are based. An evaluation of the sustainability of the groundwater use in Upper Guadiana Basin has been also carried out. The effect of five management options and a simplified climatic-change scenario have been considered for the three northern aquifers. A decrease in the net recharge, a change in river–aquifer interactions, and the total abstraction volumes authorised have been identified as the main factors to address in management planning. In addition, the expected recovery in the primary Western Mancha aquifer is shown to have little correlation with the total volume abstracted from the three northern tributary aquifers.

The summer water balance of a typical Siberian polygonal tundra catchment is investigated in order to identify the spatial and temporal dynamics of its main hydrological processes. The results show that, besides precipitation and evapotranspiration, lateral flow considerably influences the site-specific hydrological conditions. The prominent microtopography of the polygonal tundra strongly controls lateral flow and storage behaviour of the investigated catchment. Intact rims of low-centred polygons build hydrological barriers, which release storage water later in summer than polygons with degraded rims and troughs above degraded ice wedges. The barrier function of rims is strongly controlled by soil thaw, which opens new subsurface flow paths and increases subsurface hydrological connectivity. Therefore, soil thaw dynamics determine the magnitude and timing of subsurface outflow and the redistribution of storage within the catchment. Hydraulic conductivities in the elevated polygonal rims sharply decrease with the transition from organic to mineral layers. This interface causes a rapid shallow subsurface drainage of rainwater towards the depressed polygon centres and troughs. The re-release of storage water from the centres through deeper and less conductive layers helps maintain a high water table in the surface drainage network of troughs throughout the summer.

The Wadi Watir delta, in the arid Sinai Peninsula, Egypt, contains an alluvial aquifer underlain by impermeable Precambrian basement rock. The scarcity of rainfall during the last decade, combined with high pumping rates, resulted in degradation of water quality in the main supply wells along the mountain front, which has resulted in reduced groundwater pumping. Additionally, seawater intrusion along the coast has increased salinity in some wells. A three-dimensional (3D) groundwater flow model (MODFLOW) was calibrated using groundwater-level changes and pumping rates from 1982 to 2009; the groundwater recharge rate was estimated to be 1.58 X 10 (super 6) m (super 3) /year. A variable-density flow model (SEAWAT) was used to evaluate seawater intrusion for different pumping rates and well-field locations. Water chemistry and stable isotope data were used to calculate seawater mixing with groundwater along the coast. Geochemical modeling (NETPATH) determined the sources and mixing of different groundwaters from the mountainous recharge areas and within the delta aquifers; results showed that the groundwater salinity is controlled by dissolution of minerals and salts in the aquifers along flow paths and mixing of chemically different waters, including upwelling of saline groundwater and seawater intrusion. Future groundwater pumping must be closely monitored to limit these effects.

The McMurdo Dry Valleys (MDVs), Antarctica, exist in a hyperarid polar desert, underlain by deep permafrost. With an annual mean air temperature of −18 °C, the MDVs receive <10 cm snow-water equivalent each year, collecting in leeward patches across the landscape. The landscape is dominated by expansive ice-free areas of exposed soils, mountain glaciers, permanently ice-covered lakes, and stream channels. An active layer of seasonally thawed soil and sediment extends to less than 1 m from the surface. Despite the cold and low precipitation, liquid water is generated on glaciers and in snow patches during the austral summer, infiltrating the active layer. Across the MDVs, groundwater is generally confined to shallow depths and often in unsaturated conditions. The current understanding and the biogeochemical/ecological significance of four types of shallow groundwater features in the MDVs are reviewed: local soil-moisture patches that result from snow-patch melt, water tracks, wetted margins of streams and lakes, and hyporheic zones of streams. In general, each of these features enhances the movement of solutes across the landscape and generates soil conditions suitable for microbial and invertebrate communities.

Groundwater drought denotes the condition and hazard during a prolonged meteorological drought when groundwater resources decline and become unavailable or inaccessible for human use. Groundwater drought risk refers to the combined physical risk and human vulnerability associated with diminished groundwater availability and access during drought. An integrated management support tool, GRiMMS, is presented, for the mapping and assessment of relative groundwater drought risk in the Southern African Development Community (SADC) region. Based on composite mapping analysis of region-wide gridded relative indices of meteorological drought risk, hydrogeological drought proneness and human groundwater drought vulnerability, the mapping results highlight consistent areas across the region with highest groundwater drought risk and populations in the order of 39 million at risk of groundwater drought at present. Projective climate-model results suggest a potentially significant negative impact of climate change on groundwater drought risk. The tool provides a means for further attention to the key, but neglected, role of groundwater in drought management in Africa.

Karst aquifers exhibit a dual flow system characterized by interacting conduit and matrix domains. This study evaluated the coupled continuum pipe-flow framework for modeling karst groundwater flow in the Madison aquifer of western South Dakota (USA). Coupled conduit and matrix flow was simulated within a regional finite-difference model over a 10-year transient period. An existing equivalent porous medium (EPM) model was modified to include major conduit networks whose locations were constrained by dye-tracing data and environmental tracer analysis. Model calibration data included measured hydraulic heads at observation wells and estimates of discharge at four karst springs. Relative to the EPM model, the match to observation well hydraulic heads was substantially improved with the addition of conduits. The inclusion of conduit flow allowed for a simpler hydraulic conductivity distribution in the matrix continuum. Two of the high-conductivity zones in the EPM model, which were required to indirectly simulate the effects of conduits, were eliminated from the new model. This work demonstrates the utility of the coupled continuum pipe-flow method and illustrates how karst aquifer model parameterization is dependent on the physical processes that are simulated.

The areal extent of permafrost in China has been reduced by about 18.6 % during the last 30 years. Due to the combined influences of climate warming and human activities, permafrost has been degrading extensively, with marked spatiotemporal variability. Distribution and thermal regimes of permafrost and seasonal freeze-thaw processes are closely related to groundwater dynamics. Permafrost degradation and changes in frost action have extensively affected cold-regions hydrogeology. Progress on some research programs on groundwater and permafrost in two regions of China are summarized. On the Qinghai-Tibet Plateau and in mountainous northwest China, permafrost is particularly sensitive to climate change, and the permafrost hydrogeologic environment is vulnerable due to the arid climate, lower soil-moisture content, and sparse vegetative coverage, although anthropogenic activities have limited impact. In northeast China, permafrost is thermally more stable due to the moist climate and more organic soils, but the presence or preservation of permafrost is largely dependent on favorable surface coverage. Extensive and increasing human activities in some regions have considerably accelerated the degradation of permafrost, further complicating groundwater dynamics. In summary, permafrost degradation has markedly changed the cold-regions hydrogeology in China, and has led to a series of hydrological, ecological, and environmental problems of wide concern.

This report presents the World Bank Group's experience in climate and disaster resilient development and contends that it is essential to eliminate extreme poverty and achieve shared prosperity by 2030. The report argues for closer collaboration between the climate resilience and disaster risk management communities through the incorporation of climate and disaster resilience into broader development processes. Selected case studies are used to illustrate promising approaches, lessons learned, and remaining challenges all in contribution to the loss and damage discussions under the United Nations Framework Convention on Climate Change (UNFCCC). The introduction provides an overview of the UNFCCC and also introduces key concepts and definitions relevant to climate and disaster resilient development. Section two describes the impacts of globally increasing weather-related disasters in recent decades. Section three summarizes how the World Bank Group's goals to end extreme poverty and boost shared prosperity are expected to be affected by rising disaster losses in a changing climate. Section four discusses the issue of attribution in weather-related disasters, and the additional start-up costs involved in climate and disaster resilient development. Section five builds upon the processes and instruments developed by the climate resilience and the disaster risk management communities of practice to provide some early lessons learned in this increasingly merging field. Section six highlights case studies and emerging good practices in climate and disaster resilient development. Section seven concludes the report, summarizing key lessons learned and identifying potential gaps and avenues for future work. | En el informe “Crear resiliencia mediante la integración de los riesgos climáticos y de desastre en el proceso de desarrollo” se muestra por qué es esencial desarrollar la resiliencia al clima para poder alcanzar los objetivos del Grupo del Banco Mundial de poner fin a la pobreza extrema y promover la prosperidad compartida. En este resumen ejecutivo se hace un llamado a la comunidad internacional del desarrollo a trabajar en diversas disciplinas y sectores con el propósito de generar una mayor resiliencia de largo plazo, reducir los riesgos y evitar mayores costos en el futuro. Se hace hincapié en la necesidad de crear instituciones y dotarlas de los medios para emprender la continua labor que se requiere para lograr un desarrollo en que se tenga en cuenta la resiliencia al clima y a los desastres. Al destacar las mejores prácticas, el informe muestra cómo los instrumentos financieros y los programas de intervención, sumados a la experiencia y conocimientos especializados en preparación para casos de desastre adquiridos durante décadas, están ayudando a las naciones a prepararse para un mundo más expuesto a los cambios. Asimismo, en el informe se reconoce que un desarrollo con tales características tiene costos iniciales adicionales, que se amortizan en el largo plazo si se actúa correctamente. En este contexto, el informe propugna una colaboración más estrecha entre las comunidades responsables de crear resiliencia al clima y las encargadas de administrar los riesgos de desastre, y la incorporación de la resiliencia al clima y a los desastres en los procesos de desarrollo en sentido más amplio. Presenta estudios de casos seleccionados para mostrar algunos enfoques promisorios, las lecciones aprendidas y los desafíos que aún existen. | Le présent rapport explique pourquoi le renforcement de la résistance aux chocs climatiques est une condition essentielle à la réalisation des objectifs du Groupe de la Banque mondiale — mettre fin à la pauvreté extrême et promouvoir une prospérité partagée — et pourquoi il devrait constituer la clé de voûte du programme mondial de développement. À défaut d’aider les pays, les régions et les villes pauvres et vulnérables à se préparer et à s’adapter aux risques climatiques actuels et futurs, nous risquons de mettre en péril des décennies d’acquis du développement. Nous espérons que ce rapport, en s’appuyant sur l’expérience de la Banque mondiale en matière de résistance aux chocs climatiques et de préparation aux catastrophes naturelles, contribuera utilement au débat international en cours sur les moyens de lutte contre les pertes et les dommages occasionnés par le changement climatique. Le rapport reconnaît cependant qu’un tel développement exige au départ des financements supplémentaires qui s’avéreront rentables à long terme si les choses sont faites correctement. Dans ce contexte, le rapport préconise un renforcement de la collaboration entre les collectivités engagées dans l’application de mesures de résistance aux chocs climatiques et de gestion des risques de catastrophe, ainsi que l’intégration de ces mesures dans le cadre plus large de leurs processus de développement. Le rapport s’appuie sur diverses études de cas pour illustrer les démarches prometteuses, les enseignements tirés de l’expérience et les difficultés qui restent à surmonter. Le rapport entend contribuer au débat engagé dans le cadre de la Convention-cadre des Nations Unies sur les changements climatiques au sujet des pertes et des préjudices liés aux effets néfastes des changements climatiques. Il s’adresse principalement aux professionnels du développement et aux décideurs nationaux qui doivent composer avec le défi posé par une aggravation possible des catastrophes causées par l’évolution graduelle des conditions climatiques moyennes et extrêmes.

A DRASTIC-model method based on a geographic information system (GIS) was used to study groundwater vulnerability in Egirdir Lake basin (Isparta, Turkey), an alluvial area that has suffered agricultural pollution. ‘Lineament’ and ‘land use’ were added to the DRASTIC parameters, and an analytic hierarchy process (AHP) method determined the rating coefficients of each parameter. The effect of lineament and land-use parameters on the resulting vulnerability maps was determined with a single-parameter sensitivity analysis. Of the DRASTIC parameters, land use affects the aquifer vulnerability map most and lineament affects it least, after topography. A simple linear regression analysis assessed the statistical relation between groundwater nitrate concentration and the aquifer vulnerability areas; the highest R ² value was obtained with the modified-DRASTIC-AHP method. The DRASTIC vulnerability map shows that only the shoreline of Egirdir Lake and the alluvium units have high contamination potential. In this respect, the modified DRASTIC vulnerability map is quite similar. According to the modified-DRASTIC-AHP method, the lakeshore areas of Senirkent-Uluborlu and Hoyran plains, and all of the Yalvaç-Gelendost plain, have high contamination potential. Analyses confirm that groundwater nitrate content is high in these areas. By comparison, the modified-DRASTIC-AHP method has provided more valid results.

The Hydrograph model (a distributed process-based model) was applied to the simulation of soil freeze-thaw and runoff processes, to assess the viability of the model approach and the influence of specific environmental factors in a permafrost environment. Three mountainous permafrost watersheds were studied, at the Kolyma Water Balance Station in north-eastern Russia. The watersheds include rocky talus, mountainous tundra and moist larch-forest landscape regimes, and they were modelled at daily time-steps for the period 1971–1984. Simulated results of soil freeze-thaw depth and runoff showed reasonable agreement with observed values. This study reveals and mathematically describes the dependence of surface and subsurface flow on thawing depth and landscape characteristics. Process analysis and modelling in permafrost regions, including ungauged basins, is suggested, with observable properties of landscapes being used as model parameters, combined with an appropriate level of physically based conceptualization.