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• Foldscope is an efficient, low-cost, lightweight, and portable microscope. • Foldscope is an alternative for a conventional compound microscope for monitoring of the pollination process. • Foldscope can be used for field-level real-time in vivo monitoring of the pollination process. An efficient, low-cost, lightweight, and portable paper microscope can be used to monitor real-time in vivo pollination, which is not feasible with a conventional compound microscope. The advantages of paper microscopes (foldscopes) remain unexplored for in vivo field-oriented assessment of pollination. In this study, experiments were carried out to calibrate and validate the capability of foldscopes to investigate in vitro pollen traits and to understand the feasibility of using in real-time in vivo field-level investigations. Comparison of optical images of pollen morphological traits (color, size, and shape) of diverse plant species (including crops) captured using a foldscope and a compound microscope revealed little to no differences. In addition, foldscopes were calibrated to monitor and estimate in vitro pollen viability in wheat, sorghum, sunflower, chickpea, soybean, and periwinkle and to determine in vitro pollen germination in chickpea, maize, and periwinkle. Pollen tube growth was observed by time-lapse imaging of pollen from periwinkle. The foldscope efficiently captured genotypic variation in in vitro pollen germination of twelve chickpea genotypes under drought revealing the possibility of foldscopes as a tool for field level, real-time in vivo monitoring of pollination under drought. [ABSTRACT FROM AUTHOR]

Vulnerability to floods and droughts is a complex and multidimensional phenomenon influenced by various factors. This systematic review paper focuses on communities' vulnerability to floods and droughts. It presents an overview of the current knowledge on the topic, including definitions and conceptual frameworks related to vulnerability. The study synthesizes existing literature from various disciplines, including hydrology, climatology, geography, and social sciences, to identify key factors contributing to vulnerability and its impacts on communities, infrastructure, and ecosystems. Through a comprehensive analysis of 83 articles published between 2010 and 2023, this paper identifies themes, methodologies, and knowledge gaps in flood and drought vulnerability assessment. The findings reveal that vulnerability to floods and droughts depends on a range of factors, including physical exposure, socioeconomic status, governance, and cultural values. Most of the published articles have focused on regional-scale studies. There has been an increase in the number of vulnerability studies addressing this issue after 2019. Among the various methods analyzed, min-max normalization (52 % of articles) and equal weighting (27 %) were the most frequently used data normalization and aggregation methods. However, the paper identifies a significant research gap in the lack of sensitivity analysis or validation of the indices developed based on the most common parameters, such as population density, gender, income, and precipitation levels. It also emphasizes the need for true transdisciplinary approaches for a comprehensive assessment of flood and drought vulnerabilities. The systematic review concludes with a synthesis of core vulnerability indicators and recommendations for future research and policy directions aimed at reducing the vulnerability of communities to these natural hazards. • Vulnerability to flood and drought is multifaceted and influenced by various factors. • The review combines knowledge from across disciplines to better understand vulnerability. • Findings reveal key factors contributing to vulnerability and research gaps. • Vulnerability indices must include sensitivity analyses as part of their deployment. • Vulnerability must be considered through a transdisciplinary lens. [ABSTRACT FROM AUTHOR]

Droughts are significant catalysts of financial and emotional hardship for farming communities. However, does the extent of time an area has been in drought impact upon the rate at which agricultural land changes hands? Does it encourage more land to change ownership, as stressed farmers depart at faster rates, or does its negative impacts on farm production dampen demand for rural land? This study addresses this question through a unique, longitudinal (2004–2020) dataset of property transactions in 96 rural Local Government Areas (LGAs) in New South Wales, Australia. We measure the proportion of time each LGA has been in drought during the previous 1, 2, 5 and 10 years, and correlate this against the rate of agricultural land ownership change. Results indicate that in the short-term (<5 years), the proportion of time in drought is not a major influence on the extent of agricultural land ownership change. However, over a 10-year timespan, there is a statistically significant negative correlation between the two for non-irrigated agricultural land, grazing land and land owned by individuals (as opposed to companies). These findings suggest these agricultural land markets are sensitive to the long-term effects of drought. The take-home message seems to be that the persistence of drought saps the vitality of these agricultural land markets, leaving farmers with reduced prospects to capitalise on their land assets. This finding has resonance given that climate change models suggest an intensification of the frequency and severity of drought in much of rural NSW. • First study to correlate large-scale land registry data with historical Combined Drought Indicator data in Australia. • The correlation between time in drought and the rate at which agricultural land changes hands is not significant in the short-term (<5 years). • However, over a 10-year period, there is a statistically significant negative relationship between the proportion of time that a LGA has been in drought and the annual extent of agricultural land ownership change. • The paper concludes that drought has a modest, long-term inhibiting effect on the vitality of agricultural land markets. [ABSTRACT FROM AUTHOR]

Controlled drainage with subirrigation (CDSI) is a viable measure to supply, retain or discharge groundwater, thereby contributing to freshwater availability in agriculture under changing environmental conditions. Relatively simple CDSI systems can be controlled manually to set a few drainage levels. More advanced systems can be controlled remotely to set any drainage level (between a technical maximum and minimum). CDSI potentially improves hydrological conditions for crop growth, but the required external water supply can be large. Therefore, the objective of this paper is to investigate whether external water supply for subirrigation can be reduced by automatic control of CDSI systems in relation to crop water demand. Field measurements of a CDSI pilot in the Dutch sandy Pleistocene uplands were combined with weather forecasts to simulate the optimal drainage level and day by day water demand and supply using the agro-hydrological Soil, Water, Atmosphere, Plant model (SWAP). Firstly, model simulations showed that the water requirement reduced by 60 mm (dry growing season), 253 mm (average growing season) and 348 mm (wet growing season) using a dynamically managed crest level (CDSI-dyn) compared to using a fixed crest level (CDSI-fix), with minor effects on crop yield. Secondly, model simulations showed that a higher hydraulic resistance to downward seepage, a higher ditch water level or deeper roots reduced the water supply (up to 100 mm). Thirdly, accepting 10 % daily crop drought and oxygen stress for CDSI-dyn reduced the water supply requirement with 235–628 mm (dry vs wet growing season) compared to CDSI-fix. In conclusion, the required water volume for CDSI could be substantially reduced by automated control of the drainage level and water supply rate, while maintaining crop yield or accepting minor reductions, which increases the potential of implementation of CDSI systems. • Controlled drainage with subirrigation could supply, retain and discharge water. • Dynamic CDSI control reduces the water supply, while maintaining crop yield. • Accepting minor water stress may result in significant reductions in water supply. • Environmental and crop characteristics determine the total water supply. [ABSTRACT FROM AUTHOR]

Recently, we are witnessing a growing interest in the study of climate narratives and storylines. These are seen as critical tools both for improving shared understandings involving different stakeholders (including scientists from different disciplines) and guiding initiatives for transformative adaptation actions and decision making. This paper approaches the storylines about a severe drought event that took place in southeastern South America (SESA) in 2008/2009 from an interdisciplinary dialogue between climatologists and anthropologists. This approach responds to the need for a more robust understanding of the event and the responses adopted locally, i.e: not restricted to physical aspects but considering socio-economic and political aspects, with the aim of contributing to the development of socially relevant climatic information for realistic climate risk decision making contexts. In particular it intends to contribute to the decision-making processes of government agencies focused on climate communication and public climate services, such as national and weather services and regional agencies. Considering disciplinary differences, we account for the interpretative polyphony regarding this event, i.e.: what each actor/sector is talking about (for what and to whom they are talking about) when referring to "the drought", and analyze climate storylines as an agonistic field of meanings. This implies recognizing the disputes and contradictions among them, how different storylines promote certain lines of argumentation and meanings to the detriment of others, knowledge gaps, the role of social power relations, socio-political order factors and their impact in terms of the necessary transformations towards an environmentally sustainable and socially just horizon. • Interdisciplinary approach to climate storylines. • Climate storylines as an agonistic field of meanings. • Physical aspects as well as power structure's role in climate storylines. • Socio-political order factors and decision making alternatives. • Transformations towards an environmentally sustainable and socially just horizon. [ABSTRACT FROM AUTHOR]

America's worst drought spanned the 1930s, coinciding with the most extensive environmental migration in United States history. Nearly 100 years later, we know little about who moved and who stayed. This paper studies heterogeneity in migration from drought by relating migration decisions recorded in the 1940 census to county drought conditions. Drought increased migration primarily for individuals with a 12th-grade education or higher. Drought migrants, both women and men, left rural and urban locations and most often relocated to rural destinations. These findings highlight the importance of individual-level characteristics for adaptation to climate shocks, challenge the perception that rural-to-urban is the dominant environmental migrant channel, and document the central importance of drought for internal migration during the 1930s. • Drought increased migration primarily among highly educated individuals, highlighting different responses by individual human capital. • Drought-induced selection occurred across demographics, including sex and urban status, indicating a broad pattern of increased selection. • Migrants from drought areas mostly relocated to rural locations, challenging the typical rural-to-urban environmental migrant narrative. [ABSTRACT FROM AUTHOR]

• Diatoms in two springs with different surrounding land use in the Karoo compared. • Diatom indices GDI, SPI,BDI and%PTV were used to evaluate water quality. • Diatom species and indices in Great Fish River compared to historical data. • Indices at headwater site reduced ecological classification compared to previous study. This paper examines the efficacy of diatoms as bioindicators of water quality in the upper reaches of the Great Fish River following a period of reduced flow from drought conditions. Of the five sites, three were sampled three times in an 18 month period while the remaining two were sampled once. As a comparison, one headwater site within Mountain Zebra National Park, situated in the same district, was sampled. A total of 166 diatom taxa belonging to 29 genera were identified. Dominant taxa for the Great Fish River were identified as Amphora pediculus; Epithemia sorex; Nitzschia frustulum; Navicula veneta and Craticula buderi. These species, indicative of high nutrient concentrations and moderately saline to brackish conditions can tolerate low flow conditions. The Generic Diatom Index (GDI), the Specific Pollution sensitivity Index (SPI) the Biological Diatom Index (BDI) and the% Pollution Tolerant Valves (%PTV) – part of the UK Trophic Diatom Index (TDI) were used for interpretation of the results. The indices showed that this river is in poor condition. By comparison the headwater site in the Mountain Zebra National Park had Cocconeis placentula var. euglypta, Achnanthidium minutissimum and Cocconeis placentula var. lineata as dominant species and, using the same indices, the river was classified as in moderate to good condition with respect to water quality. When compared to a previous study (2010 – 2012), these sites showed a shift in dominant species indicating a change in water flow conditions and quality. [ABSTRACT FROM AUTHOR]

The focus of this paper is to develop a comprehensive understanding of the distributional impacts of disaster, especially the impact of drought on land and income, through a longitudinal study (drought year and one year after the drought) in Raikhel Village, Maharashtra, India. The key distinction of the paper is to assess the impact of the drought at the household level based on the landholding structure in the village. The paper approaches the impact of disaster in two ways: (a) by looking at the changes in land ownership as well as income due to drought based on the landholding categories in the village, and (b) by identifying the determinants of household level vulnerability due to drought using a regression model. This study shows that income from non-agriculture sources played a significant role in minimising the losses and damage as well as facilitating the recovery from the disaster. Following the drought, households moved from agriculture to non-agriculture livelihood, which are more incentivizing, as well as livelihood that is relatively less vulnerable to the disaster. The approach of the study helps in identifying the vulnerability pattern as well as protective measures that support households to cope with the disaster. [ABSTRACT FROM AUTHOR]

• Examines the politics of recent water disasters in the Bolivian Altiplano. • Water disaster politics emerges in broken cyclical relationships. • Response to broken cycles requires negotiating with nonhuman material bodies. • Intermingling determinants of water disasters complicate the search for solutions. In the floodplains of Bolivia's western highlands, or Altiplano , farmers, herders, and fishers maintain their livelihoods at water-land interfaces that are riddled with disaster risk. This paper draws on 13 months of fieldwork in the region as well as contemporary press accounts to explore water-land disasters in the Desaguadero River floodplain and Lake Poopó watershed. My analysis builds on Henri Lefebvre's notion of rhythm to articulate a "politics of cyclic dissonance" – struggles and negotiations surrounding cyclical relationships like rainfall and annual flooding that break apart and leave dangerous consequences in their wake. I analyze two recent cases in Bolivia related to climate change taken from opposite extremes of the water cycle. The first case is the drying of Lake Poopó in 2015, an event that garnered headlines around the world as a representation of a drastic impact from climate change. The second case is the struggle of farmers in a community in the Lake Poopó watershed to manage flood irrigation in their canal systems without becoming victims of flooding themselves. Both cases illustrate how managing cyclic dissonance is a matter of negotiation, both between people representing different communities, between political constituencies and political leaders, and even between people and the environment, but such politics also works to obscure solutions to environmental problems that emerge from desynchronized cycles. [ABSTRACT FROM AUTHOR]

The purpose of this study is to analyze the spatiotemporal variations in drought in Serbia over recent decades using the standardized precipitation evapotranspiration index (SPEI). The analysis is performed for time series of 1-, 3-, 6-, and 12-month SPEI indices (SPEI-01, SPEI-03, SPEI-06 and SPEI-12, respectively) calculated using the E -OBS gridded dataset with a horizontal resolution of 0.1° for the period of 1950–2022. In general, it was found that negative SPEI trends prevailed in Serbia for all months and all analyzed SPEI timescales, indicating a more frequent appearance of droughts in recent decades. Moreover, for a large majority of month-timescale combinations, the area with a negative trend was larger than the area with a positive trend. For several reasons, we focused on the SPEI for August. First, the SPEI for this month shows one of the most pronounced negative trends, which is rather consistent over different timescales and consistent in terms of the area over which the trend was found to be significant. Statistically significant negative trends of SPEI-03, −06 and − 12 for August were found over 11, 17 and 38% of the country area, respectively. To better understand the trends and changes in the SPEI for August, focusing on extreme and severe drought events, an innovative trend analysis (ITA) was applied. It was found that the occurrence of both extreme and severe SPEI drought categories has doubled over the last thirty years in comparison with the previous thirty-year period. Additionally, more frequent transitions from neutral and wet categories to dry categories were observed through an application of the Markov chain. Second, the special focus on SPEI-03, −06 and − 12 for August was motivated by the fact that we found a significant correlation between these index values and the annual maize production in Serbia, indicating that the SPEI for August can be useful for the assessment of drought impact on agriculture. To better understand interannual variability and long-term trends, this paper also explores the relations between the SPEI over Serbia and large-scale circulation patterns, together with general global and continental warming trends. Our findings indicate that drought changes over recent decades may be driven by the interplay of long-term warming and large-scale circulation patterns. In the context of climate change, especially climate projections, Serbia is situated in a region for which climate projections of mean precipitation change demonstrate weak signals and often with conflicting signs of change within multimodel ensembles. From this point of view, our results can be seen as a contribution to a better understanding of changes in extremes, in our case droughts, that can be hidden by inconclusive changes in the mean values. Finally, due to the similar situation in terms of precipitation and drought trends and changes, our results may be relevant for a wider region, and not only for Serbia. • For Serbia negative trends in SPEI index, for different months and timescales, are dominant. • Occurrence of extreme drought categories has doubled over the last decades. • Transitions from neutral and wet categories to dry categories are more frequent. • These changes are driven by long-term warming and large-scale circulation patterns. [ABSTRACT FROM AUTHOR]

Although traditional physical models have been used to analyse groundwater systems, the emergence of novel machine learning models can improve the accuracy of the predictions. Deep learning has been prominent in environmental and climate change problems. In this paper, we present a framework for utilising deep learning models to predict groundwater levels based on nearby streamflow and rainfall data. We address the missing data problem using a Bayesian linear regression model within the deep learning framework. Our deep learning framework utilises models such as long-short term memory (LSTM) networks and convolutional neural networks (CNN) for multi-step ahead time series prediction. We examine the fluctuations in groundwater levels at various boreholes located near Middle Creek in New South Wales, Australia. We use the National Collaborative Research Infrastructure Strategy (NCRIS) groundwater database and utilise Bayesian linear regression to impute missing data. We investigate the accuracy of the selected models for individual and regional basins and univariate and multivariate strategies. Our results show that the LSTM-based regional model with multivariate strategy using rainfall data provided the best accuracy. • We predict groundwater levels based on stream flow and rainfall data. • Our framework uses Bayesian data imputation and deep learning for multi-step prediction. • We examine the groundwater fluctuations at various boreholes located in Australia. • Results show a fine-tuned regional model with rainfall data yielded the best accuracy. • We find that LSTM models outperformed CNNs using the multivariate approach. [ABSTRACT FROM AUTHOR]

Across recent years, there has been a growing prevalence of extreme weather events throughout the United States, posing significant challenges to the reliable and resilient operation of power systems. Specifically, summer droughts threaten to severely reduce available generation capacity to meet regional electricity demand, potentially leading to power outages. This underscores the importance of accurate resource adequacy (RA) assessment to ensure the reliable operation of the nation's energy infrastructure. Accurately evaluating the usable capacity of regional generation fleets is a challenging undertaking due to the intricate interactions between power systems and hydro-climatic systems. This paper proposes a systematic and analytical framework to evaluate the impacts of extreme summer drought events on the available capacity of various generating technologies, incorporating both meteorological and hydrologic factors. The framework provides detailed plant-level capacity derating models for hydroelectric, thermoelectric, and renewable power plants, facilitating evaluations with high temporal and spatial resolution. The application of the proposed impact assessment framework to the 2025 generation fleet of the real-world power system within the PJM and SERC regions of the United States yields insightful results. By analyzing the daily usable capacity of 6,055 at-risk generators across the study region, it shows that the summer capacity deration is most significant for hydroelectric and once-through thermal power plants, followed by recirculating thermal power plants and combustion turbines. In the event of the recurrence of the 2007 southeastern summer drought event in the near future, the generation fleet could experience a substantial reduction in available capacity, estimated at approximately 8.5 GW, compared to typical summer conditions. The sensitivity analysis reveals that the usable capacity of the generation fleet would suffer an even more significant decrease under conditions of increasingly severe summer droughts. The proposed approach and the findings of this study provide valuable methodologies and insights, empowering stakeholders to bolster the resilience of power systems against the potentially devastating effects of future extreme drought events. [Display omitted] • A systematic summer droughts generating capacity assessment framework is developed. • Capacity derating models for various generation technologies are presented. • The impacts of summer droughts on generating fleet in PJM and SERC are studied. • Impact of extreme summer drought on usable capacity of generators is significant. [ABSTRACT FROM AUTHOR]

In Brazil, the Semi-arid is the poorest region in the country, where a significant part of the population is not adapted to drought and fluctuations in rainfall. Based on multivariate methods, I investigate here the spatial patterns of drought and socioeconomic variables between 2000 and 2010 within the Brazilian Semi-arid. In this work, I find five well-defined socio-environment clusters presenting distinct characteristics: developing cluster, demographic gains cluster, stagnated cluster, socio-environmental challenges cluster and undeveloped cluster. My results show that there are vast areas in the Brazilian Semi-arid that demand development strategies and deep structural changes. Policies for development and poverty alleviation focused essentially on increasing income will not necessarily have an immediate impact on other important social indicators, such as mortality and illiteracy rates. Multidimensional approaches and multiscale interventions considering partnerships among all levels of government (local, state and federal) are essential to overcome this vicious cycle linking environment constrains with poverty and low development levels. Finally, this paper shows that integrating socioeconomic, demographic and environmental indicators is vital to understanding development patterns throughout the Brazilian Semi-arid. • The Brazilian Semi-arid is the poorest region in the country, where a significant part of the population is not adapted to drought. • I use multivariate methods to investigate the spatial patterns of drought and socioeconomic variables within the Brazilian Semi-arid. • Our results reveal five distinct socio-environment clustering patterns in the study area. • In the region, population grows where drought is low, although it does not mean better social conditions. • Multiscale interventions within these five clusters can promote poverty alleviation and human development. [ABSTRACT FROM AUTHOR]

• Drought followed by extreme rain/flooding exposed vulnerabilities in Ceará, Brazil. • Adaptative strategies in dry periods may become maladaptive during extreme rain. • Impacts of and responses to drought, extreme rain, and flooding are interrelated. • Hydrometereological extremes should be considered together in semi-arid regions. As climates continue to change, semi-arid rainfall regimes are projected to become increasingly more extreme, with longer dry periods and fewer, but more intense, heavy rainfall events. This process of hydroclimatic intensification increases the risk associated with successive extreme climate hazards, such as drought and then heavy rainfall, in the same area. However, the development of effective adaptation strategies to drought, heavy rainfall, and flood hazards is hampered by the lack of integrated analyses that consider the interactions among these hazards and responses to them. To increase understanding of these interactions, this paper examines impacts of and adaptive actions taken in response to prolonged drought (2012–2018) and subsequent extreme rainfall and flooding (March and April 2023) in the semi-arid region of Ceará, Northeast Brazil. We find that policies and adaptive measures focus primarily on drought hazard, while preparation for extreme rainfall events and flooding is scant. Management plans and long-term adaptive strategies are being developed for drought and not other extreme hydrometeorological events. Additionally, emergency measures for extreme rainfall and flooding are much less structured than those for drought. As such, the paradigm "Convivência com o semiárido" ("Living with the semi-arid region") remains limited to adapting to drought hazard, ultimately hindering adequate extreme rainfall and drought responses. To promote more effective adaptive strategies in the context of hydroclimatic intensification in semi-arid regions, drought, heavy rainfall, and flood responses must be considered in a more integrated manner to create management plans to prepare for the potential impacts of these hazards into the future. [ABSTRACT FROM AUTHOR]

[Display omitted] • The drought pattern in China is closely related to the basin distribution and multiple teleconnection factors. • The intensity and frequency of drought in China exhibited an increasing trend. • The ENSO-AO had important positive effects in the major basins in China. • Multiple wavelet coherence helps identify the processes controlling drought changes. Due to increasing global warming and the frequent occurrence of severe drought risk in recent decades, many studies have investigated drought in China. However, the spatiotemporal heterogeneities of droughts are complicated, and a comprehensive analysis of the driving forces has not been thoroughly explored. In this paper, we studied the temporal and spatial patterns of drought in China from 1960 to 2018 and disclosed its relationship with multiple teleconnection factors on different time scales. The results show that (1) Drought in China has exhibited a fluctuating increasing trend over the past 59 years, with a standardized precipitation–evapotranspiration index (SPEI) rate of change of –0.12/10 a, and the most severe droughts occurred during 2000–2010. (2) There was a significant abrupt change in China's meteorological droughts induced by climate change around 1997. (3) The trend in China was characterized by drought in spring and autumn and humidification in winter, while the trend in the Southwest River Basin was characterized by drought. (4) A combination of factors can best explain the drought variations from basin to basin, and the El Niño-Southern Oscillation (ENSO)-Arctic Oscillation (AO) was most commonly the best predictor. The use of multiple wavelet coherence helps to identify the dominant drought change processes. [ABSTRACT FROM AUTHOR]

The world's forests are currently facing the impacts of climate change and associated extreme events, which are adversely affecting natural ecosystems and increasing risks of forest mortality. In the Mediterranean region, where water is already a limiting factor, drought stress is having a severe impact on tree growth. Different species have developed physiological mechanisms to cope with drought, and an increase in water use efficiency has been observed in several drought-tolerant species. This paper analysed the growth trends and the ecophysiological responses of four widespread Mediterranean species (Pinus pinaster Aiton, Pinus pinea L., Pinus halepensis Mill and Quercus ilex L.) to climate variability, in a natural reserve of the Vesuvio National Park (Southern Italy). Dendrochronological analyses were used to measure tree-ring widths and to estimate basal area increments for each species. Stable isotope analyses of δ13C were performed to calculate intrinsic water use efficiency on an annual scale for the four species. Climate-growth relationships suggested that temperatures, in particular annual minimum temperature, had a significant impact on the growth of each species. The species that showed the highest resistance to hot periods and water scarcity was Pinus halepensis , presenting the highest intrinsic water use efficiency values. On the other hand, Quercus ilex was found to be the most susceptible to prolonged drought periods and sensitive to changes in precipitation, resulting in the weakest growth rates during extreme heat and cold periods. Our study demonstrated the importance of better understanding the ecophysiological responses of each species to develop sound conservation and forest management plans. [ABSTRACT FROM AUTHOR]

• Resilience projects can optimize impacts on households' ability to recover from shocks by layering interventions cross-sectorally. • Projects with systems-level interventions should pro-actively plan for direct participation of households so they can take full advantage of their benefits. • Unique sampling design and data collection challenges need to be taken into account in planning complete and valid resilience impact evaluations. Developing-country households are facing an increasingly challenging set of shocks—including climate, economic, political, and health shocks—that in combination present a novel threat to their livelihoods and well-being, and thus to international development progress. There is a growing need to strengthen the evidence base for interventions and programming approaches that bolster households' resilience to such shocks. In response, this paper documents an impact evaluation of the USAID-funded "Pastoralist Areas Resilience Improvement and Market Expansion" (PRIME) project implemented from 2012 to 2017 in one of the most shock-prone areas of the world, the drylands of Ethiopia. The project's overall goal was to reduce poverty and hunger by enhancing households' ability to recover from recurring climate shocks and their downstream economic impacts. As it were, soon after its inception, the drylands were hit by an exceptionally harsh and prolonged shock, a series of multiple, back-to-back, severe droughts. The droughts led to a sharp drop in households' well-being, measured here by their food security. Using Difference-in-Difference Propensity Score Matching (DID-PSM) in one of the first causal resilience evaluations, this paper demonstrates that, nevertheless, the project's resilience-strengthening interventions had a positive impact on their ability to recover, slowing the decline in food security considerably. Delving deeper into how this impact was achieved, the paper finds that two programming approaches optimized resilience impacts. First, "Comprehensive Resilience Programming", whereby interventions spanning multiple sectors were implemented simultaneously in the same geographical areas, made a major difference. Second, while interventions were mainly implemented at a systems-level (e.g., establishing veterinary pharmacies), many households made the decision to actively participate in them. The paper finds that the impact on their resilience was far greater when they did so. The lessons for future resilience projects are that (1) greater impacts can be achieved by taking advantage of the synergies induced when interventions are layered cross-sectorally, and (2) projects with systems-level interventions should pro-actively plan for the direct participation of households so they can take full advantage of their benefits and thereby achieve greater resilience to shocks. The paper also offers some lessons for future resilience impact evaluations. [ABSTRACT FROM AUTHOR]

This paper presents findings from a stochastic benefit-cost analysis (BCA) using Monte Carlo simulations to estimate the probable values for net benefit and benefit cost ratio for a series of proposed strategic and operational water management options under climate change and socioeconomic development. The study is performed in the Tacna region in southern Peru, geographically within the Atacama Desert and under prevailing water scarcity conditions. We examined the benefits and costs to four main water users: urban, agriculture, mining and the environment over a 30-year time horizon. The main scenarios under consideration include reduced water demand from improved water use efficiency in the urban and agriculture sector, and investment in water supply infrastructure including inter-basin infrastructure and dams, a desalination plant, and increased groundwater extraction. Our findings suggest that implementation of demand-side management strategies, which in this instance is investment in water use efficiency technology and water conservation measures result in more favourable net benefit outcomes than investment in water supply infrastructures. The primary outcome of this study is to help the Regional Government of Tacna, Peruvian water authorities and water users, make more informed decisions about water investment options going forward, thereby supporting regional development opportunities. • This paper presents finding from a hydrological and economic model of drought management in Peru. • We performed a benefit cost analysis that accounts for uncertainty and stochasticity. • Our hydrological model includes operational protocols, existing and planned infrastructure, and demand management options. • Our findings suggest that demand-side management strategies are more favourable than water infrastructures investment. [ABSTRACT FROM AUTHOR]

• An ecosystem process model-based NEP was predicted under varying climate scenarios. • Alpine grasslands were projected to play an important part in carbon sink contributions in Qinghai Province in the 21st century. • An earlier peak and faster decreasing NEP projected for a warmer climate scenario (RCP 8.5). • A more stable carbon sink was projected under a less warm, stable precipitation scenario (RCP 4.5). The alpine grasslands of the Qinghai-Tibetan Plateau play an important role in multiple ecosystem functions, all of which are key in regulating regional climate influences and providing pristine headwaters for millions of people downstream from this basin. Alpine grasslands act as a carbon sink, storing carbon dioxide and keeping heat-trapping greenhouse gases out of the atmosphere, but it is not clear how this will change in a warming climate in the future. In this paper, the net ecosystem productivity (NEP) of alpine grasslands in Qinghai province, on the Qinghai-Tibetan Plateau, was predicted for the period from 2010 to 2099. Trends and stability were analyzed under two climate scenarios, Representative Concentration Pathway 4.5 (RCP4.5) and 8.5 (RCP8.5) representing the lower and higher emission scenarios for greenhouse gases. The results suggest that grasslands will continue to contribute as a carbon sink, with a positive NEP through this century. Almost the same magnitude (38 Tg C a-1, 1 T g = 1012 g) of contribution was projected under both scenarios. Grasslands are projected to be the major contributor to NEP in Qinghai province, with more than 89% of NEP in the future. The carbon sink function will increase over more than 69% of the grasslands and peak around 2069 (RCP4.5) or 2066 (RCP8.5). Then the carbon sink function will begin to decrease and it will decrease more quickly and become more variable under the RCP8.5 than the RCP4.5. The impacts of temperature and precipitation changes were analyzed and NEP was found to be more sensitive to temperature than precipitation change. The trend of increasing contribution to NEP is driven by a warming climate, while the stability of NEP is mainly influenced by the precipitation, which results in an upward trend before the peak and a decline due to stresses from limits in available water in a continued warming climate. [ABSTRACT FROM AUTHOR]

[Display omitted] • Droughts and floods are increasing worldwide. • Changes in soil moisture affect the soil microbiome. • Climate change affects the soil environment. • Changes in the soil environment affect crop production. • Drought and floods have a negative impact on agriculture. Climate change is progressing and is already visible to the naked eye around the world. Hydrological events associated with climate change, i.e. floods and droughts, have reached extreme levels in recent years. Researchers warn that these phenomena will continue to intensify. According to recent reports, the number of extreme weather events, including hydrological phenomena, has increased by 60% in Europe over the last three decades. Both water shortages and water surpluses affect the soil environment and its functions. This in turn has a direct impact on crops and agriculture. For example, in the US alone, droughts and floods were responsible for more than 70% of the decline in cereal yields in 2011 alone. However, the soil environment is a complex ecosystem that is not yet fully understood, making it difficult to predict the impact of climate change on its quality and functioning. In this paper, we discuss the effects of floods and droughts on the soil microbiome and the implications of these changes for agriculture. We suggest that changes in soil moisture are an important factor affecting crop growth and yield, which is of great importance for global food security. [ABSTRACT FROM AUTHOR]

Floods and droughts can cause severe impacts for communities. Even with different temporal and spatial scales, these extreme events challenge risk management specially when happening simultaneously, cascadingly or cumulatively over time. However, the number of articles that evaluates the joint occurrence (i.e., interplay) between floods and drought in the same area is still limited in literature. In this sense, this paper aims to evaluate what lessons we can learn from previous studies on both extreme events, and to identify the way forward for understanding floods-droughts interplay and risk reduction in the future. For this, we developed a literature review with articles from 2008 to 2021, aiming mainly to understand the "dual-risks" context internationally (n = 60). Articles are analysed with chronological, descriptive, and geographical factors, methodological aspects, main objectives, and risks interplay. Results show articles still focuses most on the single hazards approach, and when considering the risks interplay, they focus more on risk assessments rather than on assessing the context conditions of communities and their vulnerabilities. This study concludes by discussing the key elements for integrating floods and droughts, including the analysis of local conditions (i.e., social, political, cultural, and physical aspects) vulnerabilities, and the participation of stakeholders. [Display omitted] [ABSTRACT FROM AUTHOR]

• Based on the principles of SPEI, we develop a GDAI. • The relationship between GDAI and AI is closer. • The correlation between GDAI and SPEI is also better. Climate change has increased the risk of drought in both arid and non-arid regions of the globe. Therefore, in order to monitor and evaluate global drought and aridity, based on the principle of standardized precipitation evapotranspiration index (SPEI), this paper selected precipitation and potential evapotranspiration data and used a frequency calculation method to develop a multi-scale global drought aridity index (GDAI) that concurrently considers spatial and temporal variation characteristics: the spatiotemporal standardized precipitation evapotranspiration index. The index was compared with the aridity index (AI) and SPEI. The results showed that the correlation coefficients between GDAI and AI were greater than 0.8 in most areas, and the relationship was closer and could reveal the global aridity and wetness zoning. In addition, the correlation between GDAI and SPEI was also better, which could capture the temporal change characteristics of drought. Moreover, this study also compared the grades of GDAI and SPEI with the actual drought grades in Yunnan from September 2009 to August 2010, and found that GDAI was better than SPEI, and GDAI was the most accurately evaluated at the 3 month time scale, with an accuracy rate of 86.11%. Therefore, this index is more helpful for the assessment and monitoring of global drought and aridity. [ABSTRACT FROM AUTHOR]

Interstate conflicts are complex and often have a multitude of causes. These factors can be social, economic, or cultural. One social factor receiving little attention in the literature is international migration. This paper uses climate shocks as a driver of emigration to study the causal impact of immigration on conflicts. We find that climate-induced immigration increases the probability that the destination country initiates a conflict against the origin. This effect is moderated by attitudes in the receiving country and features of the specific flows. The results imply that countries severely impacted by climate change may face an exodus of migrants and be forced to confront conflicts initiated by the destination countries of these migrants. • Climate-induced migration is a driver of interstate conflicts. • The effect is moderated by attitudes in the receiving country. • Climate also directly contributes to interstate conflicts. [ABSTRACT FROM AUTHOR]

The Mediterranean Basin has been identified as a climate change "hotspot", a region where increased warming and drying are expected to occur at rates faster than the global average. Increasing scientific attention has therefore been drawn to the repercussions of climate change for the Mediterranean's diverse and valued agricultural sector. The extent to which these repercussions vary throughout the region, owing both to a non-uniform distribution of climatic hazards and to uneven adaptive capacities of farmers, remains however unquantified. We hereby provide a comprehensive spatial assessment of the potential to implement different farm-based land and water management adaptations across the Mediterranean's croplands, and evaluate the extent to which different regions see a match or a mismatch between areas of adaptation need and areas of adaptation capacity. This approach made use of spatial multi-criteria analysis to evaluate the suitability of different farm adaptations, and relied on the Ecocrop climate suitability model and climate data on changing duration or frequency of extremes to identify areas of adaptation need under a high-end climate change scenario. The adaptations explored in this work span a range of sustainable approaches addressing different components of the farming system (soil-based, water-based, and crop-based adaptations). For each sub-system, we compared the potential to implement an adaptation representing an incremental change vs. one involving greater transformation. Results indicate a worsening of climatic conditions for all croplands in the region, and particularly within the Mediterranean extents of Egypt, Turkey, Greece, Spain, Morocco, Bosnia and Herzegovina, and Israel. In more than half of these countries, >60% of highly affected Mediterranean areas, on average, see no tangible potential to implement adaptations. Importantly, potentials for adaptation, and particularly of transformational adaptations having the greatest hypothesized capacity to buffer against the effects of climate change, are found to be lower within areas where the most adverse climate change hazards are forecast to occur. For regions found to be approaching so-called limits to adaptation, this research contributes to growing calls for consideration of more transformational options, alongside the opportunities and sacrifices these options entail. For regions where considerable (yet unrealized) adaptation capacity is found to match areas of adaptation need, this paper instead presents a basis for further investigation on how to bridge adaptation capacity and preparedness. [Display omitted] • Mediterranean croplands will witness increased drought and heat stress under RCP 8.5. • Croplands in the south-west and east will face the greatest increases in climatic extremes. • Most regions have a > 50% spatial mismatch between adaptation potential and needs. • Adaptation potential is lower where most needed, especially for transformational adaptations. • Greater reflection on transformation needed as limits to adaptation are approached. [ABSTRACT FROM AUTHOR]

Using a panel of nearly 3000 agricultural households in Tanzania and Mozambique from 2016–2018, this paper investigates the associations of nutritional outcomes and agricultural management practices under drought risk. We show drought has significant consequences on two nutritional outcomes in particular: food security and dietary diversity. Importantly, these consequences are evident even for households using improved management practices, such as improved seed, chemical fertilizer, and production diversity. This finding has important implications in the context of how policy makers use the tools at their disposal – including both promotion of improved agricultural management practices and direct transfers – to prevent costly coping strategies that reduce future resilience. • Dietary diversity and food security capture different nutritional outcomes • Drought has serious consequences on both dietary diversity and food security • Best management practices (BMPs) are associated with improved nutritional outcomes • The positive associations of BMPs do not fully offset drought's consequences [ABSTRACT FROM AUTHOR]

Standardized drought indices such as the Standardized Precipitation Index (SPI) or the Standardized Precipitation and Evapotranspiration Index (SPEI) are frequently used around the world to assess drought severity across a continent or a larger region covering different meteorological regimes. But how standard are these standardized indices? In this paper we quantify the uncertainty of SPI and SPEI based on an Austrian dataset to shed light on what are the main sources of uncertainty in the study area. Five factors that either defy the control of the analyst (record length, observation period), or need to be subjectively decided during the steps of the calculation (choice of the distribution, parameter estimation method, and GOF-test of the fitted distribution) are considered. We use the root mean squared error (E R M S) for estimating the typical error for different calculation algorithm of SPI and SPEI. The total and relative uncertainty components for each factor are analysed by a linear mixed model (LMM) and significance of each model parameter are tested by the Akaike information criterion (AIC) and the restricted likelihood ratio test. The E R M S indicates that computational variations of standardized drought indices lead to highly variable results. From the LMM, the choice of the distribution and the observational window are the most important sources of uncertainty. They, on average, control between 19% and 63% (choice of distribution) and 24% to 70% (observation period) of the total variance of the SPI across all stations and month of the year, with similar values observed for the SPEI. The parameter estimation method and the GOF-tests, however, have almost no effect on the standardized indices. Total errors and observation period uncertainty are typically decreasing with the record length as one would expect, while the distribution uncertainty is almost independent from the record length. An additional assessment shows that the uncertainties are similar at the pan-European scale leading to uncertain characterizations of major events such as the drought of 2015. Overall, the uncertainty of standardized drought indices is substantial. Alternative approaches as nonparametric methods, ensemble approaches or probability-based indices based on established methods of extreme-value statistics should be considered, to make the indices more accurate. • A novel error model sheds light on the accuracy of drought indices SPI and SPEI. • Main sources of uncertainty are observation period and choice of distribution. • Parameter estimation methods and GOF tests have almost no effect. • Errors are substantial and may yield to false classifications of drought events. • Concepts are discussed to make drought indices more accurate. [ABSTRACT FROM AUTHOR]

In this paper, daily modulating behaviors of Indian summer monsoon rainfall (ISMR) has been evaluated over eight important sub-zones of India viz Northwest India (NWI); Northcentral India (NCI); West Peninsular India (WPI); Eastern Peninsular India (EPI); Southern Peninsular India (SoPI); Central India (CI), Northeast India (NEI) and Western Ghat (WG) using latest SA-CORDEX simulated climate data during 1981–2015. The climate extreme indices, standardized precipitation index (SPI) and empirical orthogonal function (EOF) have been utilized to uncover substantial regional spatial patterns and temporal variability of monsoon precipitation over India and its sub regions to understand the regional modulation of these events based on duration, frequency and severity. The comprehensive assessment of ISMR modulated characteristics (intensity, spell, and frequency) were showing significant decreasing trend over NEI and NCI which can be leading factors for demarcating major hotspots for land degradation, effective management and adaptation towards water resources and hazards related to the flood/drought events. India has received flood events (1983, 1988, 1994, 2005, 2011, 2013) and drought event (1982, 1987, 2002, 2004 and 2009) during 1981–2015, which have been verified with SA-CORDEX RCMs (RegCM4.7, COSMO & REMO2015) using SPI. The first mode of EOF(IMD), explained 17% of the total SPI variability on the interannual scale, shows anomalous large positive values concentrated over the western peninsular region and extending towards central India as well as the NWI region of India. On the other hand, high anomalous negative values dominated over the NEI and eastern parts of the Indo-Gangetic Plain. Therefore, this study underscores the importance to uncover the prevalent dynamics and climate change variability on changing trend variability of the precipitation indices, drought and flood characteristics. As moderate to severe drought variability portrays a diversity over regional scale viz northwest India, north central India, eastern ghat of the southern peninsular region and northeast India while the occurrence of moderate to severe flood are dominated towards Himalaya region (26°N-35°N; 70°E-80°E), western peninsular region and western ghat. • Modulating behavior of regionalized daily ISMR shows a significant decreasing trend over northeast and north-central India. • Moderate to severe drought portrays significant variability over regional scale viz. NWI, NCI, eastern ghat of SPI and NEI. • Occurrence of moderate to severe flood events are more dominated in the Himalaya region, WPI and WGs. • Critically regionalized hotspots susceptible to drought and flood have been demarcated. [ABSTRACT FROM AUTHOR]

Global-level warming largely influences drought dynamics. Therefore, a robust drought projection is critical to support sustainable development under a future warming climate, especially at the regional level (i.e., South Asia). Encouraged by the Paris Agreement, this study investigates the changes in the intensity, area, and duration of future droughts under 1.5 °C, 2.0 °C, 3.0 °C, and 4.0 °C global warming levels over South Asia. In this regard, seven global climate model outputs under seven newly designed climate change scenarios (SSP1-1.9, SSP1-2.6, SSP2-4.5, SSP3-7.0, SSP4-3.4, SSP4-6.0, and SSP5-8.5) from the sixth phase of the Coupled Model Intercomparison Project (CMIP6) are used. The standardized precipitation evapotranspiration index (SPEI), self-calibrating Palmer drought severity index (scPDSI), and intensity-area-duration (IAD) method are adopted to characterize drought. Drought events are identified considering an area coverage greater than 50,000 km2 for predefined drought durations of 3- (short-term), 6- (medium-term), and 12-month (long-term). A significant drying trend is seen and tested against the two-sample t -test. Notably, to represent the more concrete picture of changes in drought characteristics, the results based on two indices (SPEI and scPDSI) are combined (average) in this paper. The results reveal that droughts with higher-intensity, and long-term duration will increase with continued warming. As drought features, the number of long-term droughts will increase by 21.5% (highest), and the leading area coverage is also estimated (>7%) for long-term drought at higher warming (i.e.4.0 °C) than the reference period (1995–2014). Furthermore, drought events with large-area (>3 × 105 km2) coverage are projected to become more frequent. For drought severity, extreme drought events and associated area coverage are more likely to unfold over the region. However, overall drought conditions are inclined to worsen under higher warming, especially 4.0 °C warming. Importantly, for global warming targets set by the Paris Agreement (1.5 °C and 2.0 °C), drought conditions will be more acute at 2.0 °C than at 1.5 °C. Spatially, a significant drying trend is mainly observed in the western part of South Asia (Southwest-Northwest) according to both drought metrics (SPEI and scPDSI). Notably, NW will experience acute droughts under all warming levels. Droughts in this region will be mainly influenced by the combined effect of decreasing precipitation and escalated evapotranspiration. As global warming increases, a significant increase in PET and temperature is found over South Asia. In addition, the model evaluation shows that the CMIP6-Global climate models (GCMs) are capable of satisfactorily reproducing climate variables and drought events in South Asia. However, our study's findings strongly support the execution of the Paris Agreement target and provide a scientific basis for articulating drought adaptation measures at the regional scale, especially in South Asia. • Intensity-Area-Duration approach is used to analyze future drought over South Asia for 1.5oC - 4.0oC warming. • The modified Penman-Monteith method (considering CO 2) are adopted to estimate PET. • Overall drought conditions will worsen under 4.0oC warming. • The Northwest of South Asia is inclined to be affected by intense drought in the future. [ABSTRACT FROM AUTHOR]

The importance of climate change, specifically drought, across the Maya region in the northern Neotropics, remains a topic of lively debate. Part of this discussion hinges on the coherency of response to climatic variability across different archives and proxies. In this paper we present a 6600-year palaeolimnological record from Yaal Chac, a carbonate lake (known locally as a cenote) in the northern lowlands of the Yucatan Peninsula, < 2 km from the location of the previously published Aguada X'Caamal record. The Yaal Chac sequence has been analysed for loss-on-ignition (LOI), stable isotopes (δ18O, δ13C) and elemental analysis using μXRF, complemented by some mineralogical, charcoal and pigment data. Mid Holocene sediments, predating evidence of human impact, are carbonate dominated and finely laminated. δ18O values are positive (>2‰), but show no covariation with δ13C. A major transition occurs at ca. 4360 cal yr BP, with a change to generally more organic sediments and increased variability in all proxies. Although direct evidence for anthropogenic activity in the Yaal Chac catchment is limited, it seems feasible that human impact was affecting the system. Comparison with other records from the Northern Maya lowlands and the wider region shows little coherence in the mid Holocene, when Yaal Chac seems to have been quite stable, but possibly responsive to increased climatic seasonality, driving the production of seasonal laminae. In the late Holocene, when the climate was generally more variable, there is more coherence between Yaal Chac and other regional records, including the so called Pan Caribbean Dry Period (3500–2500 cal yr BP) and the droughts of the late Pre-Classic period (1800–1600 cal yr BP). The Yaal Chac record shows no evidence of drought at the time of either the Maya 'hiatus' or the Maya 'collapse' of the Terminal Classic, but does record drying from the 14th to 19th centuries CE, in keeping with other proxy and historical records. This new record from Yaal Chac highlights the spatial variability of responses to climate forcings and the importance of recognising individual system sensitivity. • A new 6600 year palaeolimnological record from Yaal Chac in the northern Maya lowlands. • Finely laminated, carbonate dominated sediments until ca. 4360 cal yr BP, then major transition. • Mid Holocene record seems to reflect enhanced seasonality in an otherwise stable climatic regime. • Late Holocene increased climatic variability and more regional coherence. • No evidence for severe drought at the time of the Maya 'hiatus' or the Maya 'collapse'. [ABSTRACT FROM AUTHOR]

• Litterfall sampling in a deciduous forest indicated disturbance effects on leaf abundance. • Decline of sugar maple in this forest preceded the initiation of sampling in 1993. • Decline of canopy American beech was compensated by expansion of understory beech. • Calcium addition probably caused an increase in leaf abundance of sugar maple. Leaf abundance of trees plays a dominant role in energy, water and nutrient flux of forest ecosystems, in defining the habitat structure of entrained biota and in mediating interspecific competition among tree species. We quantified leaf abundance of three dominant tree species (Acer saccharum Marsh.; Fagus grandifolia Ehrh.; Betula alleghaniensis Britt.) for 27 years in mature northern hardwood forest at the Hubbard Brook Experimental Forest, New Hampshire, USA using annual counts of leaves of each species collected in 117 litter traps (0.1 m2, each). We hypothesized that variation in leaf abundance would reflect known disturbance events and canopy dieback episodes. No significant trend in leaf abundance of the three species over 27 years (1993–2019) was observed in seven reference stands despite known canopy dieback of sugar maple and American beech in these stands, indicating that 1) maple decline preceded our sampling interval and 2) expansion of beech understory compensated for canopy dieback caused by beech bark disease. Leaf abundance temporarily declined significantly in response to known disturbances (ice storm, 34 to 47%; late-spring frost, 13 to 16%). Increased leaf abundance, especially for sugar maple (30%), on a watershed where calcium addition restored acidified soils, was probably associated with increased soil pH, Ca availability and decreased Al. The temporal sequence of decline of paper birch at higher elevations following a severe drought in 2002 also was apparent. Leaf abundance based on leaf litterfall in deciduous forests provides a useful indicator of forest ecosystem function and forest health. [ABSTRACT FROM AUTHOR]

This paper revives a fascinating debate: did a drought start before, during, or after the collapse of the Andean polity of Tiwanaku? Here we present an alternate age model that highlights the real issue: the data from Lake Orurillo, no matter the age model, are too imprecise to address the question. The authors neglect the significance of four-century error ranges (95% probability) for a drought that lasted a single century, according to their estimates. They are content to treat an imprecise correlation between drought and collapse as a causal relationship. Future efforts will require much greater attention to refining both paleoclimate and cultural chronologies, which is a necessary first step in understanding complex episodes of human–environment interaction. [ABSTRACT FROM AUTHOR]