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Bai et al. ([3]) in their article «Impact of climate change on water transfer scale of inter-basin water diversion project» present a systematic approach for runoff prediction, impact analysis, and risk assessment under climate change. Elnashar and Elyamany ([8], [9]) in the paper «Managing Risks of Climate Change on Irrigation Water in Arid Regions», propose a systematic approach to identify, analyse, and respond to the risks of climate change on irrigation water in arid regions using a Risk Management process. In the paper «Complex policy mixes are needed to cope with agricultural water demands under climate change» by Martinez-Valderrama et al. ([23]) the authors argue that the forecast of the water gap (difference between agricultural water use and annual supply of water resources) will continue to widen, affecting the water security of a large part of the world's population. Elnashar and Elyamany ([8], [9]) in the paper «Adapting Irrigation Strategies to Mitigate Climate Change Impacts: A Value Engineering Approach» accept the fact that climate change will increase water demand and decrease crop yields. [Extracted from the article]

Flash droughts, characterized by rapid onset and development, present significant challenges to agriculture and climate mitigation strategies. Operational drought monitoring systems, based on precipitation, soil moisture deficits, or temperature anomalies, often fall short in timely detection of these events, underscoring the need for customized identification and monitoring indices that account for the rapidity of flash drought onset. Recognizing this need, this paper introduces a global flash drought inventory from 1990 to 2021 derived using the Soil Moisture Volatility Index (SMVI). Our work expands the application of the SMVI methodology, previously focused on the United States, to a global scale, providing a tool for understanding and predicting these rapidly developing phenomena. The dataset encompasses detailed event characteristics, including onset, duration, and severity, across diverse climate zones. By integrating atmospheric variables through their impact on soil moisture, the inventory offers a platform for analyzing the drivers and impacts of flash droughts, and serves as a large, consistent dataset for use in training and evaluating flash drought prediction models. [ABSTRACT FROM AUTHOR]

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This bibliographic article on Drought and Water Level examined the relationship between organizations, nations, institutions, authors, references, and publishers. It examined 742 papers from Web of Science at the Nanjing University of Information Science and Technology's. The total annual publication volume of articles was increased steadily from 2012 to 2021, with China and the United States ranking first and second in terms of publication volume and citations but in quality Switzerland and England were top-level. Institutional-partnership analyses indicated disparities in network density and connections, with the Chinese Academy of Sciences (2012) receiving the highest citations and degrees. The document co-citation analysis (DCA) network was created to improve understanding of the frequency and amplitude of bursts of various publications in separate clusters. The most cited work was J Hydrol (2012), with 302 citations. The analytical tool from CiteSpace collected high-frequency keywords and performed co-occurrence, grouping, and emerging word recognition. Gorges Dam is the most crowded cluster, followed by drought stress. The greatest burst duration and most significant phrase is reservoir (2019), followed by "water quality," which has a 5 year burst period. Estuaries perform important functions such as water purification and coastal. "Reservoir, water quality, restoration, phytoplankton, temperature, wetland, time series, diversity and carbon dioxide" are the most important terms, while "climate change, drought, water level, impact, growth, variability, response, dynamics, management and model" are the most frequently used keywords. In terms of citations, references, and academic influence, Zhang Q. (2012), the R Core team (2014), and Jappen E. (2015) were the top three contributors. Cook, ER (2013), and Allen, R.G. (2019) ranked first and second in terms of frequency, respectively. In this review work, significant information gaps were discovered in the areas of microbiological dynamics, environmental variables, fen peat incubation, lake water, drought risk reduction, biological ecology, lake acidification, salinity variations, and attribution. Future researchers should focus on these and similar topics, while Chinese and USA authors should concentrate on article quality rather than publishing numbers. [ABSTRACT FROM AUTHOR]

The future risk for droughts and water shortages calls for substantial efforts by authorities to adapt at local levels. Understanding their perception of drought hazards, risk and vulnerability can help to identify drivers of and barriers to drought risk planning and management in a changing climate at the local level. This paper presents a novel interdisciplinary drought case study in Sweden that integrates soft data from a nationwide survey among more than 100 local practitioners and hard data based on hydrological measurements to provide a holistic assessment of the links between drought severity and the perceived levels of drought severity, impacts, preparedness, and management for two consecutive drought events. The paper highlights challenges for drought risk planning and management in a changing climate at the local level and elaborates on how improved understanding of local practitioners to plan for climate change adaptation can be achieved. [ABSTRACT FROM AUTHOR]

Agro-pastoral ecotone of northern China is the prominent area for agricultural production, but it is also the most typical ecological fragile area with frequent drought disasters. Taking Yulin City at Shaanxi Province in China as the case area, the paper aims to investigate the spatio-temporal changes of agricultural vulnerability to drought in China's agro-pastoral ecotone in the period 2000 to 2020. The results show that: 1) the agricultural vulnerability to drought in Yulin City has shifted from high vulnerability in the period 2000–2010 to low vulnerability in the period 2011–2020. 2) There exist obvious spatio-temporal differences of the agricultural vulnerability to drought in Yulin City during the research period. 3) Four sensitive events and 14 resilient events were identified in the research and the crops of Yulin had become more resilient to drought. Finally, the paper put forward with policy implications to make adaptive strategies of agriculture to climate change in China's agro-pastoral ecotone in the future, e.g., carrying out agricultural zoning based on agricultural production conditions, intensifying the construction of disaster prevention and relief system, and integrating with modern agricultural technology to develop new type agriculture. [ABSTRACT FROM AUTHOR]

In the paper, the frequency and spatial distribution of atmospheric and hydrological droughts over the territory of Belarus in 1945–2020 is assessed. Aridity is evaluated using the standardized precipitation and streamflow indices (SPI and SSFI). Trends in monthly total precipitation are determined, the features of the streamflow formation during the open-channel period are revealed. The frequency of anticyclones that determines hydrometeorological conditions on the territory of Belarus is calculated. The statistically significant increase in the number of the days with anticyclonic weather over the country during the warm season is found. The increasing frequency of dry conditions in summer months against the background of a rise in the precipitation intensity is highlighted. A simultaneous increase in the frequency of very-low-flow periods on rivers and an increase in the height of warm rainfall floods in some river basins are revealed. [ABSTRACT FROM AUTHOR]

Rural populations are particularly exposed to increasing weather variability, notably through agriculture. In this paper, we exploit longitudinal data for Turkish provinces from 2008 to 2018 together with precipitation records over more than 30 years to quantify how variability in a standardized precipitation index (SPI) affects out-migration as an adaptation mechanism. Doing so, we document the role of three potential causal channels: per capita income, agricultural output, and local conflicts. Our results show that negative SPI shocks (droughts) are associated with higher out-migration in rural provinces. A mediated-moderator approach further suggests that changes in per capita income account for more than one quarter of the direct effect of droughts on out-migration, whereas agricultural output is only relevant for provinces in the upper quartile of crop production. Finally, we find evidence that local conflict fatalities increase with drought and trigger out-migration, although this channel is distinct from the direct effect of SPI shocks on out-migration. [ABSTRACT FROM AUTHOR]

Agricultural sectors worldwide are under direct threat from climate change conditions. In Iran, agricultural production has decreased due to droughts originating in an increase in annual maximum temperatures—with the corresponding increase in crop respiration and evapotranspiration—and a decrease in accumulated precipitation. Based on a static computable general equilibrium approach, this paper reports implication for the Iranian economy from the effects of climate change on agriculture––as modeled through three scenarios relying on assumptions about the magnitude of continued reduction in total agricultural production. Reductions of 6%, 12%, and 18% in total agricultural production reasonably cover the range of impacts that climate change is expected to impose on the Iranian agricultural sector––under the assumption that no behavioral adaptations or policy interventions are in place. Our simulations suggest that effects on the Iranian economy imply a reduction in GDP ranging between 3.7 and 6.3%. In addition, 5–17% of labor moves away from the agriculture sector––this labor relocation occurs due to declining agriculture incomes. Findings illustrate that climate change will reduce households' consumption and income in all economic sectors, particularly among rural households. We suggest that policies in Iran should focus on improving cultivation methods to save water resources and alleviate the expected effects of climate change. The current study's outcomes are helpful for policymakers, especially in countries with water scarcity. [ABSTRACT FROM AUTHOR]

Copyright of Advances in Atmospheric Sciences is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Ecological environment is the essential material basis of human survival and connects regional economy with socially sustainable development. However, climate changes characterized by global climate warming have caused a series of ecological environmental problems in recent years. Few studies have discussed various climate factors affecting the ecological environment, and the spatial non-stationary effects of different climate factors on the ecological environment are still unclear. Dynamically monitoring ecological environment changes in fragile areas and identifying its climate-driving mechanism are essential for ecological protection and environmental repair. Taking Zoige Plateau as a case, this paper simulated the eco-environmental quality during 1987–2020 using remote sensing data, utilized Geodetector method to identify the contributions of various climate drivers to ecological environment quality, and then adopted the Geographically Weighted Regression model to explore the spatial non-stationary impacts of climate factors on ecological environment quality. The results showed that the ecological quality in the middle regions of the Zoige Plateau was slightly better than in the surrounding marginal areas. For the whole area of Zoige Plateau, the average ecological environment quality index was 54.92, 53.99, 56.17, 57.88, 63.44, 56.93, 59.43, and 59.76 in 1987, 1992, 1997, 2001, 2006, 2013, 2016 and 2020, respectively, which indicated that eco-environmental quality witnessed several fluctuations during the study period but showed a generally increasing trend. Among five climate factors, the temperature was the dominant climate factor affecting the ecological environment quality (q value: 0.11–0.19), sunshine duration (0.03–0.17), wind speed (0.03–0.11), and precipitation (0.03–0.08) were the main climate drivers, while the explanatory power of relative humidity to ecological environment quality was relatively small. Such various climate factors impacting the ecological environment quality demonstrated distinct spatial non-stationary and the range of driving impact varied with time. Temperature, sunshine duration, wind speed, and relative humidity promoted ecological environment quality in most regions (regression coefficients > 0), while precipitation mainly had a negative inhibitory impact (regression coefficients < 0). Meanwhile, the greater impacts of these five climate factors were concentrated in high-elevation regions of the south and west or the northern areas. The appropriate enhancement of climate warming and air humidity was beneficial to the improvement of the ecological environment, but the excessive precipitation would result in landslides and exhibit inhibition of vegetation growth. Therefore, selecting cold-tolerant herbs and shrubs, and strengthening climate monitoring and early warning systems (such as drought and excessive precipitation) are essential for ecological restoration. [ABSTRACT FROM AUTHOR]

Drought is a natural phenomenon that occurred in Central Europe in the past, but it is becoming a more serious problem due to the changes in its occurrence and intensity related to climate change. The main aim of this paper was to determine changes in air temperature and precipitation amounts in Slovakia from 1931 to 2020 and to identify changes in drought occurrence and intensity using the Standardised Precipitation and Evapotranspiration Index (SPEI). Cluster analysis was used to determine regions with similar drought occurrences. For each of the identified five clusters, drought characteristics were determined and compared between two reference periods 1961–1990 and 1991–2020. While a decrease in the number of months with SPEI-1 below − 1 was observed in autumn, spring and summer months showed a drying tendency. Overall, we can say that we observed a shift in drought occurrence from autumn and winter months to spring and summer months. This is an important finding for the agriculture or forestry because it affects work management and planning. The clearest tendency in drought events was observed in the western part of Slovakia covering areas with agriculturally intensive land use. Besides prolonging drought events, there was also a higher accumulated deficit for each event. The increase in drought intensity was not spatially consistent over the cluster area, mostly reaching a slight decline of about − 0.1 to − 0.3, which means slight intensification of drought periods in 1991–2020. [ABSTRACT FROM AUTHOR]

The impacts of climate change increasingly show themselves in many forms in our everyday lives such as heatwaves and droughts. Drought is one of the critical events today for increasing drought frequency. This study focuses on meteorological drought because it directly affects other drought types. Hence, this study focuses on how the future drought conditions will vary under climate change effects in the Mediterranean basin (Turkey). In doing so, this study utilizes precipitation data from three General Circulation Models (GCMs) and three Regional Circulation Models (RCMs). The GCMs are CNRM-CM6, GFDL-CM4, and MPI-ESM1, while the RCMs are (RCA4)-CNRM-CM5, (Reg CM4)-GFDL-ESM2M, and (RCA4)-MPI-ESM-MR. Mitigating biases of the climate models, this study utilizes four statistical downscaling methods (SD), linear scaling (LS), local intensity scaling (LOCI), power transformation (PT), and distribution mapping (DM). Here, the study has two purposes. The main aim of the paper here is to compare the performance of SD methods in improving the representation of observed climate variables in climate models. In addition, the study shows how different methods will affect the spatial drought distribution in the area under the SSP2 4.5 and SSP5 8.5 scenarios. Consequently, the study uses the standardized precipitation index (SPI) and Z-score index (ZSI) to quantify future drought conditions and reaches the following results. The study reveals that mild drought conditions are prevalent in the basin for future periods, and drought indices go down to − 0.55. The study also shows that different SD methods affect the results obtained by each climate model diversely. For example, while the LS method causes the most drought conditions on the results based on CNRM-CM5 and CNRM-CM6, the DM method has a similar impact on outcomes based on GFDL-CM4 and GFDL-ESM2M and causes the most drought conditions. [ABSTRACT FROM AUTHOR]

The low-lying Vietnamese Mekong Delta (VMD) is a key agricultural production landscape increasingly threatened by anthropogenic stresses and climate change. Among the different threats, droughts caused by extreme events, climate change and upstream developments, affect the delta the most. This paper explores the relationship between the intensity, duration, and frequency of meteorological droughts and hydrological droughts using a range of indices. We used monthly rainfall and stream flow data for the period 1992–2021 to calculate the Standardized Precipitation Index (SPI), the Reconnaissance Drought Index (RDI), and the streamflow drought Index (SDI) for different time intervals. We found no observed time lag, and a strong correlation coefficient between upstream hydrological and downstream meteorological drought events assessed over long-term scales (i.e., 12-months). This is true for all downstream sites, except Ben Tre City. Hydrological drought events onset lagged 5–6-, 6-, and 3–4-month behind meteorological droughts at mid- and shorter assessment time scales (9-, 6-, 3-month). The average correlation coefficients between hydrological indices and meteorological indices at 9–3-month time scales ranged from moderate to weak. These findings shed light and advance the understanding of the progression of meteorological to hydrological droughts in the VMD. Our results aid the regional understanding of drought onset and the causative mechanisms at work, which is important for both medium- and long-term drought forecasting and adaptation planning. [ABSTRACT FROM AUTHOR]

For an effective reservoir operation during drought, the variations of both water supply and water demand which depend on hydrological and meteorological conditions need to be dealt with. This paper aimed to consider these variations in the Aharchay basin (Iran) by coupling a hedging rule (HR)-based reservoir operation model (HRROM) with a climate-based irrigation scheduling model (CBISM) at the farm level. Through the HRROM, optimal long-term decisions for Sattarkhan reservoir were made by considering the probable streamflow scenarios in the system. Given the variable agricultural demands (VAD) in the CBISM, the irrigation water was optimally allocated to the crops using several evapotranspiration (ET) scenarios. The CBISM employs three sub-models including linear programming (LP), nonlinear programming (NLP), and particle swarm optimization (PSO) to maximize the total income of the Aharchay agricultural network as a function of the climate factors and the supplied water. To this end, the daily weather and discharge data from 1990 to 2015 were used in this study. The standardized precipitation-evapotranspiration index (SPEI) and the streamflow drought index (SDI) were used to detect the meteorological and hydrological droughts, respectively. The SPEI was calculated based on the high-resolution-gridded datasets of the Climatic Research Unit (CRU). The findings demonstrated that the HRROM-CBISM generally managed to increase the time-based (αt) and volume-based (αv) reliability indices by 20% and 44%, respectively, compared with the conventional standard operation policy (SOP). For more investigations, the three major droughts of 2000–2002, 2004–2006, and 2008–2014 were separately analyzed. The average values of αt, αv, and vulnerability (V) for SOP were 0.33, 0.51, and 0.48, respectively. With the HRROM-CBISM, these values were about 0.5, 0.55, and 0.45, respectively. Among these indices, αt had the highest variations, while αv had the lowest variations in both the SOP and HRROM-CBISM approaches. The average water shortage for the mentioned droughts was significantly decreased from 89 (SOP) to 75 MCM (HRROM-CBISM). [ABSTRACT FROM AUTHOR]

In the next 20 years, there will be an extensive investment in transport infrastructure. Although the cut and embankment slopes seem to have the same appearance, they have different responses to climate variations. Understanding their characteristics and performance is necessary to design a safer and more sustainable slope infrastructure. This paper provides a thorough examination of the seasonal performance of cut slopes and embankments. Furthermore, this study suggests an introduction to the impacts of climate change, amplifying seasonal shrinkage–swelling and progressive failure of slope construction under extreme drought and precipitation. Volumetric water content and pore water pressure fluctuations due to seasonal variation were analysed and compared from both the cut slope and the embankment. Moreover, stress path and slope deformation were also investigated in this study to understand the behaviour of the cut slope and the embankment. The results suggest that the cut slope retains more pore water pressure during the wet season due to its lower permeability than an embankment with respect to the construction history. However, pore water pressure and displacement in the cut slope tend to be increased due to the consolidation process after excavation, which requires more time to reach equilibrium. In addition, greater displacement in the cut slope can increase the possibility of delayed failure in the future. [ABSTRACT FROM AUTHOR]

Research into weather circulation changes over the UK for future climate has mainly focused on changes in the Summer and Winter seasons, with less analysis on seasonality and the transition seasons. Using the 30 Met Office weather patterns we examine the influence of climate change on seasonality through atmospheric circulation using a number of climate models. Changes in seasonality are important as they can have large impacts on many sectors including agriculture, energy and tourism. This paper finds a noticeable increase in Autumn over the UK in the frequency of drier summer-type regimes and a decrease in stormy winter types that emerge as early as the 2020s. The change in circulation signal once isolated from the overall signal is responsible for a 4–12% decrease in Autumn mean rainfall on average for England by the end of this century (where the values in the range are dependent on the emissions scenario). This change is projected over English regions that are already experiencing water stress, and with predictions of drier summers over the UK in future, this could further increase drought risk. The change in circulation in Autumn also moderates the large increase in the number of large-scale extreme daily rainfall events over the same regions predicted due to climate change. While this future circulation change is replicated across all the climate models used, large differences remain in the strength of the signal between models. The climate models used replicate the frequency of the 30 weather patterns well for all seasons. [ABSTRACT FROM AUTHOR]

Due to global climate change, droughts are likely to become more frequent and more severe in many regions such as in South Africa. In Limpopo, observed high climate variability and projected future climate change will likely increase future maize production risks. This paper evaluates drought patterns in Limpopo at two representative sites. We studied how drought patterns are projected to change under future climatic conditions as an important step in identifying adaptation measures (e.g., breeding maize ideotypes resilient to future conditions). Thirty-year time horizons were analyzed, considering three emission scenarios and five global climate models. We applied the WOFOST crop model to simulate maize crop growth and yield formation over South Africa's summer season. We considered three different crop emergence dates. Drought indices indicated that mainly in the scenario SSP5-8.5 (2051–2080), Univen and Syferkuil will experience worsened drought conditions (DC) in the future. Maize yield tends to decline and future changes in the emergence date seem to impact yield significantly. A possible alternative is to delay sowing date to November or December to reduce the potential yield losses. The grain filling period tends to decrease in the future, and a decrease in the duration of the growth cycle is very likely. Combinations of changed sowing time with more drought tolerant maize cultivars having a longer post-anthesis phase will likely reduce the potential negative impact of climate change on maize. [ABSTRACT FROM AUTHOR]

Climate change may cause adverse impact on agricultural production that could jeopardize food availability and security. In this paper, we investigate how changes in mean values and variability of weather variables may affect rice yield using panel data for 30 districts of Tamil Nadu State from 1971 to 2018. We estimate a fixed-effects regression model with panel-corrected standard errors. Results show that rainfall and temperature have a statistically significant impact on rice yield. Furthermore, weather variability, measured as standard deviations of temperature and rainfall, has a negative effect on rice yields. We use the Coupled Model Inter-comparison Project-5 outputs and dynamically downscaled the weather outputs using the regional climate model. The results of the climate model showed that the rise in temperature and disruptions in rainfall patterns including both excessive and deficient rainfall events in Tamil Nadu will continue in the future under different climate scenarios. Projected changes in the weather variables are likely to decrease rice yield in Tamil Nadu from 0.7 to 6.3% under the low emission scenario and 4.1 to 20.1% in the high emission scenario during 2022–2050 (relative to 1971–2018). These projections have implications for the planning and targeting of climate adaptation technologies such as drought-tolerant and flood-tolerant varieties to lessen the adverse impact of weather variability due to climate change in the future. [ABSTRACT FROM AUTHOR]

The flood protection embankments of Hungary and Europe face numerous challenges. Some dike bases were constructed more than 200 years ago; since then, they have been elevated and extended. Because of these iterative adaptations, the dikes bear many construction errors, which can trigger failures and slides. Due to climate change, droughts and low-water periods of the rivers in central Europe are becoming more frequent. As a result of these effects, the water balance of the dikes can alter and desiccate in the long term. The most staggering fissures appeared on dikes built from clays susceptible to volume change. The General Directorate of Water Management ordered a comprehensive survey of dike pavement cracks in Hungary. This was one of the most extensive surveys of such kind. Hungary has some 4400 km of primary flood protection embankments, out of which 1250 km is paved. There are multiple reasons why the pavement of an embankment can crack. The main features of crack patterns related to clays with shrink-swell potential are identified. The results of international studies and the present survey are synthesised. The main objective of this paper is to draw a correlation between drought (aridity) zones, plasticity index of the soil samples, and crack thickness. [ABSTRACT FROM AUTHOR]

Climate change affects the hydrological cycle and has a significant influence on water resources, which can lead to environmental and socioeconomic damage caused by droughts. This phenomenon has become more acute in recent years. Among the indices used to assess the extent of droughts, the Reconnaissance Drought Index (RDI) is being adopted throughout the world. The RDI requires a stationarity assumption in its statistical calculations; however, most of the hydro-meteorological time series show non-stationarity. Hence, this paper seeks to assess meteorological droughts by means of RDI by adopting both stationary and non-stationary approaches. Non-stationarity was assessed by applying the Mann–Kendall test for trend detection and the Pettitt test for change point detection. The Thornthwaite method was employed to estimate the potential evapotranspiration required for RDI application. The bias in the future series were corrected employing the Linear Scaling (LS) technique for precipitation series and the Empirical Quantile Mapping (EQM) technique for the temperature series. Historical and future simulated monthly temperature and precipitation data were obtained from 34 meteorological stations located within Parana State, Brazil. The results showed that the maximum drought magnitude, duration, and intensity have increased during the 21st Century. When compared with historical patterns up to 2100, the results showed that drought magnitude is expected to increase by 105%, while drought duration is expected to increase by 59% in meteorological drought projections. [ABSTRACT FROM AUTHOR]

The paper presents the dynamics of the hydrothermal coefficients characterizing agroclimatic resources on the territory of Siberia within the coordinates of 50°–65° N, 60°–120° E during modern climate change. The intensity, frequency, and duration of adverse weather phenomena for agriculture (the atmospheric droughts and moisture excess conditions) are analyzed. The Ped' drought index () and the standardized precipitation evapotranspiration index (SPEI) calculated from the data of 134 weather stations and the ERA5 reanalysis are used as an indicator. In Eastern Siberia and in the west of the analyzed territory, there is an increase in aridity (a trend is 0.2–0.5 per decade). Northern regions of Kazakhstan, the Sayan Mountains, and the West Siberian Plain were characterized by a relative stability of hydrothermal conditions in 1950–2020 (statistically significant changes are not revealed). A direct linear dependence of hydrothermal conditions on large-scale circulation processes have been not detected for most cases. The greatest number of statistically significant correlation coefficients has been obtained for the drought index and the SCAND (Scandinavia teleconnection pattern) index. [ABSTRACT FROM AUTHOR]

This paper analyzes long-term time series of annual and seasonal water and ionic runoff of the Northern Dvina River measured near the village of Ust'-Pinega, where hydrological and hydrometric observations commenced in 1882 and 1947, respectively. Long increased and decreased-runoff phases have been distinguished and their main parameters determined. It is established that the difference between the increased and decreased-runoff phases in long-run annual average water runoff values is 17% for the annual runoff, 16% for the snow-melt flood runoff, 32% for the winter runoff, and 38% for the summer–autumn runoff. It is concluded that changes in the chemical runoff during the transition from a increased water runoff phase to a decreased water runoff phase are pronounced to a lesser extent. The greatest differences between the contrasting water runoff phases in ionic runoff are typical for the summer–autumn hydrological season and for the winter low-water season: during increased-runoff phases, the ionic runoff is 14–17 and 10–11% higher, respectively, compared to decreased-runoff phases. During snow-melt flood periods and on average for the year as a whole, the ionic runoff during increased water runoff phases is only 5–8% higher compared to decreased water runoff phases. The relative dynamic constancy of the hydrochemical load exerted by the Northern Dvina River on the White Sea, regardless of its water content fluctuations, is determined by an inverse relationship between the water flow and the concentration of chemicals. In addition, the anthropogenic impact on the ionic composition in the river catchment basin is insignificant, which makes it possible to maintain the established relationships despite ongoing climate change. [ABSTRACT FROM AUTHOR]

Drought is often one of environmental disasters replicated in Morocco. It is the result of climate variations and human activity that has affected different sectors (water resources, agriculture, ecology, and socio-economy, etc.). The normalized water differential index (NDWI) is a type of spectral water analysis based on one green band and one NIR-band representation. The NDWI was effectively used to gather information around water bodies from remote sensing data. The study area for this work is the Idriss 1st Dam in northeast Morocco, situated downstream from the drainage of the Inaouene River. This basin is mostly affected by drought risk, which will evaluate by calculating NDWI index of image time series, based on Sentinel-2 (2015 to 2020), Landsat-8 (2013 to 2020) and Google Earth Engine (2013 to 2020) as a data processing tool. For the study area drought monitoring, DrinC software is used to calculate the Standardized Precipitation Index (SPI) and the Stream-flow Drought Index (SDI).The result of this paper is mapping water bodies of Idriss 1st Dam, and evaluated drought risk severity and frequency with a high precision. [ABSTRACT FROM AUTHOR]

With global climate change and the rapid urbanization, urban flood and drought disasters are frequent and urban water supply systems are facing a sea of serious challenges. It is crucial to assess the resilience of urban water supply systems and develop corresponding disaster mitigation and improvement strategies. Urban water supply systems include many subsystems, but existing researches generally focus on a single subsystem. Therefore, this paper proposes a correlation analysis method and a factor analysis method for the resilience evaluation index system of urban water supply systems by combining each subsystem and applying grey system theory. The method can reflect the four dimensions of the water supply process (water source, water plant, supply and distribution network and users) and the five dimensions of the urban management system (society, natural environment, economy, physics and organization). Taking Qingdao as an example, a multi-level integrated evaluation model based on a cloud model is applied to simulate and analyze the resilience of Qingdao's water supply system. As a result, decision support is provided for planning and building resilience systems for urban water systems in the short and long term, based on four main factors. [ABSTRACT FROM AUTHOR]

Climate change is one of the multiple challenges facing all categories of farmers globally. However, African farmers are the most sensitive in respect of climate variability and change. Climate change impacted negatively on crop production and the livelihoods of the local farmers. In black township South Africa, agricultural activities are highly dominated by small-scale farmers, whose farming system is highly vulnerable to changes in climate. This paper presents the analysis of how small-scale farmers employed adaptation strategies in response to climate change and determinants of small-scale households' choices of coping and adaptation approach to climate variability and change in Vhembe District, South Africa. Multi nominal logit model was used on a surveyed of 224 local farmers. Farmers' socio-economic attributes, was used in response to climate changes and further, households have adaptation strategies both on-farm and off-farm approach. Such approaches were; drought-tolerant seeds, shorter cycle crops, diversification of crops, changing planting dates, small-scale irrigation, migrating to urban areas and involvement in petty business. The results of the findings reveals that the significant drivers affecting choice of adaptation approach include climate information, gender, farm size, education level, farmer experience, decreasing rainfall and increases in temperature as farmers' determinant choices of adaptation to climate change. While, on the other hand, off-farm resources, headed households and age had no significant impact on the choice of coping and adaptation approach to climate change. Therefore, policy makers in the local municipality should play a significant role by enhancing adaptation strategies appropriate for particular climatic shock on the study area. [ABSTRACT FROM AUTHOR]

This paper examines drought trends in Turkey due to climate change. Therefore, forecasting of periods of drought, which is one of the major negative side effects of climate change, is urgent. The authors use data on drought indicators according to the SPEI (Standardized Precipitation and Evapotranspiration Index) for the period from 1901 to 2015 obtained at intervals of 1, 3, 6, and 12 months. The data have been processed by several statistical tests: the Mann–Kendall test to determine the direction and significance of the trend, the Theil–Sen estimator to assess the trend slope coefficient, and the Pettitt test to determine the most probable year of change. The period under study is divided into two intervals (1901–1981 and 1982–2015), which are compared. The GIS program is used to isolate spatial characteristics from the results we obtained. It is concluded that Turkey is divided into two main zones of drought trends. The largest one allocated to the northern regions is characterized by an increase in moisture, and a decrease in moisture is observed in the southern regions. The trend towards dry periods was more significant until 1981, but the situation has changed since 1981 due to the trend towards excess moisture, except for southeastern Turkey, where a trend towards droughts persists. [ABSTRACT FROM AUTHOR]

Global climate change is identified as a major threat to survival of natural ecosystems. Climate change is a dynamic, multifaceted system of alterations in environmental conditions that affect abiotic and biotic components of the world. It results in alteration in environmental conditions such as heat waves, intensity of rainfall, CO2 concentration and temperature that lead to rise in new pests, weeds and pathogens. Climate change is one of the major constraints limiting plant growth and development worldwide. It impairs growth, disturbs photosynthesis, and reduces physiological responses in plants. The variations in global climate have gained the attention of researchers worldwide, as these changes negatively affect the agriculture by reducing crop productivity and food security. With this background, this review focuses on the effects of elevated atmospheric CO2 concentration, temperature, drought and salinity on the morphology, physiology and biochemistry of plants. Furthermore, this paper outlines an overview on the reactive oxygen species (ROS) production and their impact on the biochemical and molecular status of plants with increased climatic variations. Also additionally, different tolerance strategies adopted by plants to combat environmental adversities have been discussed. [ABSTRACT FROM AUTHOR]

Concerning the various effects of climate change on intensifying extreme weather phenomena all around the world, studying its possible consequences in the following years has attracted the attention of researchers. As the drought characteristics identified by drought indices are highly significant in investigating the possible future drought, the Copula function is employed in many studies. In this study, the two- and three-variable Copula functions were employed for calculating the return period of drought events for the historical, the near future, and the far future periods. In this paper, bivariate and trivariate of Copula functions were applied to evaluate the return periods of the drought in the historical period and the two near and near future periods. Moreover, the results of considering bivariate and trivariate of Copula functions were compared separately with the results of the calculated return periods for each of the drought characteristics; accordingly, the role of each drought characteristics was considered. The most severe historical drought was selected as the benchmark, and the drought-zoning map for the GCM models was drawn. The results showed that severe droughts could be experienced, especially in the upper area of the basin where the primary water resource is located. In addition, the nature of the drought duration plays a decisive role in calculating the return periods of drought events. [ABSTRACT FROM AUTHOR]

This paper used original survey data in Shandong province of China to depict local farmers' perceptions of combined climatic and market risks, and their adaptive behaviors. Two Logit models were developed to capture the empirical relationship between farmers' risk perception of the combined risks and adaptive behaviors. Results show that farmer's risk perception of climate change and market significantly affected their adoption behavior of adaptive measures, including perception of rainfall decrease, gale decrease, drought increase, and price fall of agricultural products. Moreover farmers' adaptive behaviors are more sensitive to their perceptions of extreme climatic events. Addition of demographic factors can improve the explanatory capacity of the Logit model. As illustrated by the models, male and better educated farmers have greater willingness to take actions for averting risks, while household heads with bigger farm are more reluctant. A majority of respondents chose to construct farm structure for irrigation and water conservation to avert climatic risks. Insurance, which is regarded as an effective tool to help farmers mitigate risks and avoid losses, has not been sufficiently accepted by farmers in rural areas in Shandong province. This underscores the need of effective communication of knowledge to enhance farmers' coping capacity and to encourage their active response to risk. [ABSTRACT FROM AUTHOR]

Background: Climate change is expected to affect plant–soil feedbacks (PSFs, i.e., the effects of a plant on the growth of another plant or community grown in the same soil via changes in soil abiotic and biotic properties), influencing plant community dynamics and, through this, ecosystem functioning. However, our knowledge of the effects of climate changes on the magnitude and direction of PSFs remains limited, with considerable variability between studies. We quantified PSFs associated with common climate change factors, specifically drought and warming, and their corresponding ambient (control) conditions using a meta-analytical approach. We investigated whether drought and warming effects on PSFs were consistent across functional groups, life histories (annual versus perennial) and species origin (native versus non-native), planting (monoculture, mixed culture) and experimental (field, greenhouse/laboratory) conditions. Results: PSFs were negative (a mechanism that encourage species co-existence) under drought and neutral under corresponding ambient conditions, whereas PSFs were negative under both ambient and elevated temperatures, with no apparent difference in effect size. The response to drought was largely driven by stronger negative PSFs in grasses, indicating that grasses are more likely to show stronger negative PSFs than other functional groups under drought. Moreover, non-native species showed negative drought-induced PSFs while native species showed neutral PSFs under drought. By contrast, we found the opposite in pattern in response to warming for native and non-native species. Perennial herbs displayed stronger drought-induced negative PSFs than annual herbs. Mixed species communities displayed more negative PSFs than monocultures, independent of climate treatment. Finally, warming and drought treatment PSF effect sizes were more negative in experiments performed in the field than under controlled conditions. Conclusions: We provide evidence that drought and warming can induce context-specific shifts in PSFs, which are dependent on plant functional groups, life history traits and experimental conditions. These shifts would be expected to have implications for plant community dynamics under projected climate change scenarios. [ABSTRACT FROM AUTHOR]

The North Western Himalayan region, particularly the Kashmir valley, harbors a rich diversity of rice landraces, yet systematic studies on climate resilience are lacking. The present study was aimed at investigating the root traits and their interplay with shoot morphological and physiological traits under drought stress using seven indica and three japonica rice varieties released by SKUAST-Kashmir and their possible role in adaptive capacity to different environments. Significant variability was observed in root and shoot traits across the varieties. Root traits exhibited a wide phenotypic range, including rooting depth, fresh and dry weight, diameter, length, volume, surface area, and length density. Associations between root and shoot traits were identified, with notable correlations such as shoot weight with root shoot ratio, shoot length with root dry weight, diameter, and surface area, and tiller number with various root traits. Additionally, physiological traits like canopy temperature depression showed significant correlations with root depth and surface area. Principal component analysis (PCA) analysis grouped japonica type varieties together with a notable outlier, Chenab, due to its superior root traits among indica varieties. These findings emphasize the substantial contribution of root traits to productivity and advocate for their integration into varietal development processes. In view of the increasing evidences in crop plants about their role of root traits in defining plant productivity and reproductive fitness, study of root traits could provide valuable insights into the patterns of crop adaptation to diverse areas and growing environments. [ABSTRACT FROM AUTHOR]

Background: The potential ecosystem collapse of forests in Mediterranean-type ecosystems (MTEs) by unprecedented droughts is worrisome due to the impacts on its exceptional biodiversity and human well-being. However, research integrating the impacts of global change drivers, forest resilience and the challenges facing human-nature relationships is still scarce. Methods and results: Using the central Chile megadrought and recently massive forest browning event as a model scenario, we identified, through a scientific literature review and an interdisciplinary scientific workshop, the research priorities and questions to address for MTEs in a context of global change. Our results highlighted knowledge gaps that need to be covered, particularly in social and environmental sciences, with an emphasis on soil science. Research priorities must focus on (1) the understanding of interactive effects of global and local anthropogenic drivers on MTEs and (2) the evaluation of the potential impacts of MTEs collapse on human well-being and ecosystem functioning. Conclusions: We highlight the need for a collaborative approach involving scientists, landowners, managers/administrators, and policymakers to apply adaptive forest management against the current socio-environmental challenges under a global change context. [ABSTRACT FROM AUTHOR]

Global warming and climate change impacts intensify hydrological cycle and consequently unprecedented drought and flood appear in different parts of the world. Meteorological drought assessments are widely evaluated by the concept of standardized precipitation index (SPI), which provides drought classification. Its application is based on the probabilistic standardization procedure, but in the literature, there is a confusion with the statistical standardization procedure. This paper provides distinctive differences between the two approaches and provides the application of a better method. As a novel approach, SPI classification is coupled with fuzzy clustering procedure, which provides drought evaluation procedure based on two variables jointly, precipitation and temperature, which is referred to as the standard precipitation-temperature index (SPTI). The final product is in the form of fuzzy c-means clustering in five clusters with exposition of annual drought membership degrees (MDs) for each cluster and resulting objective function. The application of the proposed fuzzy methodology is presented for the long-term annual precipitation and temperature records from New Jersey Statewide records. [ABSTRACT FROM AUTHOR]

Drought will increasingly threaten forest ecosystems worldwide. Understanding how competition influences tree growth response to drought is essential for forest management aiming at climate change adaptation. However, published results from individual case studies are heterogeneous and sometimes contradictory. We reviewed 166 cases from the peer-reviewed literature to assess the influence of stand-level competition on tree growth response to drought. We monitored five indicators of tree growth response: mean sensitivity (inter-annual tree ring width variability); association between inter-annual growth variability and water availability; resistance; recovery; and resilience to drought. Vote counting did not indicate a consistent effect of competition on mean sensitivity. Conversely, higher competition for resources strengthened the association between water availability and inter-annual growth rates. Meta-analysis showed that higher competition reduced resistance (p < 0.001) and improved recovery (p < 0.05), but did not consistently affect resilience. Species, site and stand characteristics, and drought intensity were insignificant or poor predictors for the large variability among the investigated cases. Our review and meta-analysis show that competition does not affect the response of tree growth to drought in a unidirectional and universal way. Although density reduction (thinning) can alleviate growth declines during drought, the effects on growth after stress are uncertain. The large variability among investigated cases suggests that local-scale processes play a crucial role in determining such responses and should be explicitly evaluated and integrated into specific strategies for adaptation of forests to climate change. [ABSTRACT FROM AUTHOR]

In a poorly understood yet recurring phenomenon, communities occupying diverse settings within a region may undertake large-scale migrations that cannot be easily attributed to single variables such as climate change. As a result, the study of these movements has increasingly focused on the distinct histories of localities to address how they may have articulated as large-scale abandonments. We adopt this micro-history perspective on the fourteenth to fifteenth century depopulation of a large portion of the North American Midwest and Southeast, popularly referred to as the Vacant Quarter. Our research on the Middle Cumberland drainage within the Vacant Quarter suggests that a significant exodus began slowly ca. 1300 CE; then, it accelerated extremely rapidly in the first half of the fifteenth century CE. This genesis of this trajectory seems to be related to a pattern of severe droughts, but it was brought to a close by social and demographic challenges such as endemic conflict and adverse health conditions. [ABSTRACT FROM AUTHOR]

Understanding divergent perceptions of ethnic groups to climate change in mountainous regions home to multi-ethnic cultures and the factors influencing these perceptions is crucial for policymakers to predict the trending impacts of climate change and make long-term decisions. Based on the case of Southwest China, 1216 households were interviewed by questionnaire surveys to gain insight into the perceptions of local people on the dynamic evolution characteristics of climate events in the uplands of Yunnan, China, which is an area home to rich ethnic diversity, and also to determine the factors that influence these perceptions. Results indicated that climate events have now become important events for farmers' livelihoods, ranking only after family diseases and livestock diseases. Drought, long-term drought, and erratic rainfall are the three kinds of climatic events with the most significant increase in frequency and severity in mountainous areas. Farmers' perceptions on whether drought, long-term drought, and erratic rainfall occurred 10 years ago as well as changes in frequency and severity are significantly influenced by characteristics of respondents, ethnic culture, geographical environment of farmer residences, farmland characteristics, and sources of livelihood. Ultimately, taking ethnic differences into consideration for long-term planning will be an important part of the local response to climate change in the future. [ABSTRACT FROM AUTHOR]

The goal of this study is to examine the association between in utero drought exposure and epigenetic age acceleration (EAA) in a global climate change hot spot. Calculations of EAA in adults using DNA methylation have been found to accurately predict chronic disease and longevity. However, fewer studies have examined EAA in children, and drought exposure in utero has not been investigated. Additionally, studies of EAA in low-income countries with diverse populations are rare. We assess EAA using epigenetic clocks and two DNAm-based pace-of-aging measurements from whole saliva samples in 104 drought-exposed children and 109 same-sex sibling controls in northern Kenya. We find a positive association between in utero drought exposure and EAA in two epigenetic clocks (Hannum's and GrimAge) and a negative association in the DNAm based telomere length (DNAmTL) clock. The combined impact of drought's multiple deleterious stressors may reduce overall life expectancy through accelerated epigenetic aging. The study suggests a positive association between in utero drought exposure and faster biological aging in children in a global climate change hot spot. Drought experienced during pregnancy may reduce life expectancy. [ABSTRACT FROM AUTHOR]

Background: Deciphering the genetic architecture of drought tolerance could allow the candidate genes identification responding to water stress. In the Andean Patagonian forest, the genus Nothofagus represents an ecologically relevant species to be included in different genomic studies. These studies are scarce in South American ecosystems however represent an important source of genomic data in order to interpret future climate-change environment scenarios of these emblematic forests. Here, we achieved the assemblage of the transcriptome of N. alpina while searching for key genes of activated or suppressed metabolic pathways in response to drought stress. Results: De novo transcriptome assembly resulted in 104,030 transcripts. Following confirmation of drought conditions, based on reduction of leaf water potential and stomatal conductance, a differential gene expression analysis resulted in 2720 significantly expressed genes (1601 up-regulated and 1119 down-regulated). Enrichment analysis (over-representation analysis and gene set enrichment analysis) resulted in more than one hundred stress-responsive term ontologies (i.e. biological processes) and pathways. Terms such as response to abscisic acid and pathways such as plant hormone signal transduction or starch and sucrose metabolism were over-represented. Protein–protein interaction assessment resulted in networks with significantly expressed top common hub gene clusters (e.g. plant-type cell wall biogenesis among down-regulated or ABA-signalling among up-regulated). These networks evidenced important regulators at gene expression such as transcriptional factors. Conclusions: Responses of N. alpina seedlings to drought stress were evidenced by the activation of several genes linked to GO biological processes and KEGG pathways, which were mainly based on over-expression of specific protein kinases, phosphatases, synthases and transcription factors. This suggests an up-regulation of signalling pathways, triggered through plant hormones such as abscisic acid or auxin, which could counteract the osmotic stress created as a probable immediate response to drought. On the other hand, groups of carbon fixation genes related to the galactose metabolism, photosynthesis, secondary wall biogenesis, and fatty acid biosynthesis degradation were down-regulated under drought. Overall, our results provide new genomic data for understanding how non-model long-lived trees of Patagonian forests would acclimate to environmental changes. [ABSTRACT FROM AUTHOR]

The knowledge about vulnerability of tree seedlings to severe droughts is important in order to select the most suitable species for forestry plantations in a context of extreme weather events induced by global climate change. We conducted a study aiming to evaluate the effects of lethal leaf dehydration on seedlings of nine tropical tree species cohabiting the same forest ecosystem, but differing in terms shade tolerance, maximum height, geographical distribution, and leaf mass per area. For this, the percentual loss of photochemical efficiency, measured as the loss of maximum quantum efficiency of photosystem II during leaf dehydration (PL[Fv/Fm]) was investigated. Statistically significant differences were found between species for the average values ​​of the relative water content (RWC) in which there is a loss of 10% and 50% of Fv/Fm. The species were separated in three groups: (a) species that showed the highest Fv/Fm losses at high RWC values, (b) intermediate species, and (c) species that showed significant Fv/Fm loss only at very low values of RWC. The PL[Fv/Fm] during leaf dehydration can be an useful methodology to select tree species for plantations in sites prone to severe droughts associated to extreme weather events. [ABSTRACT FROM AUTHOR]

Weather, trade restrictions, rising oil prices, a lack of financial support for farmers, and other factors have contributed to the destabilization of South Asian food security. The purpose of this study is to determine the long-run and short-run relationships between climate change, agricultural credit, renewable energy, and food security for a sample of South Asian countries between 1990 and 2021. The Dynamic Common Correlated technique is utilized for empirical analysis since it directly addresses the issue of cross-sectional dependency while delivering accurate cointegration findings. The study's empirical findings show that climate change reduces food availability and increases the incidence of food insecurity in South Asia. In contrast, the use of renewable energy sources has a positive effect on food security in the short-run but not in the long-run, while the availability of credit to farmers has a positive effect on food security. Findings suggest that South Asian countries may reduce climate change's negative effect on food security by investing in climate services, climate-resilient infrastructure, growing drought-resistant crops, using supplemental reinforced agricultural practices, and improving their weather forecasting capabilities. [ABSTRACT FROM AUTHOR]

Climate change is affecting the global hydrological cycle, causing drastic changes in precipitation patterns. Extreme climatic events are becoming more frequent and intense than in the past, leading to water-level fluctuations and affecting aquatic ecosystems. Semiarid regions are very susceptible to changing climate. We analyzed a 10 years dataset from a tropical semiarid reservoir during extreme hydrological events (heavy rains and prolonged drought), and evaluated phytoplankton functional responses to environmental conditions. We found, as hypothesized, that phytoplankton functional structure change in a temporal scale due to water–volume fluctuation induced by the rainfall pattern. Depth and inorganic material acted as environmental filters selecting phytoplankton groups. High water level seems to improve water quality and low water level worsen it. Colonial and filamentous cyanobacteria dominate the wet period; however, it may have a critical threshold during severe periods of drought, which will lead to dominance of groups well adapted to low light conditions and with mixotrophic metabolism. Phytoplankton functional approaches can simplify phytoplankton identification and reflect better the environmental conditions than the taxonomic approach. Therefore, these approaches can help to understand the shifts in aquatic ecosystems under extreme hydrological events and predict functional response of phytoplankton being an important tool to water management and conservation. [ABSTRACT FROM AUTHOR]

Background: Treeline ecotones of Mediterranean ecoregions have been affected by the increasing intensity and severity of droughts. Even though the effect of droughts on forest dynamics has been widely documented, knowledge is relatively scarce of how extreme climate episodes affect the hydraulic structure and, therefore, the physiology of woody plants. The Mediterranean Andes have experienced an uninterrupted period of drought since 2010, including an extremely dry year in 2019 with approximately 80% rainfall deficit. Here, we investigated shifts in wood anatomical and physiological traits of Kageneckia angustifolia, an endemic treeline species, in response to this drought period. Methods: We evaluated the xylem plasticity of three K. angustifolia populations across their natural distribution (31–35° SL) based on anatomical (vessel structure and distribution) and physiological (intrinsic water-use efficiency) variables in the tree rings. We focused on the period 2000–2020 that corresponds to before the megadrought (2000–2007), (ii) megadrought (2008–2018) and (iii) hyperdrought (2019–2020). The variables were annualized and analyzed by linear mixed-effects models. Results: Our results provide insights to the anatomical and physiological mechanisms underlying the resilience of treeline forests to persistent droughts in central Chile. We found that the extreme drought in 2019–2020 triggered shifts in vessel size and frequency that increased hydraulic safety. These significant shifts in vessel traits occurred in parallel with a decrease in pit aperture area and an increase in water-use efficiency, further increasing the resilience of K. angustifolia to extreme drought stress. Conclusions: Our results revealed coordinated shifts in vessel size and frequency and water-use efficiency in response to the megadrought, thereby reducing vulnerability to hydraulic failure. The apparent resilience of K. angustifolia to extreme droughts suggests that this adaptation to drought stress may increase its ability to tolerate novel climatic conditions of treeline environments of the Mediterranean Andes, although it is not clear whether these adaptations will be sufficient to persist in scenarios that predict intensification of climate stress. Finally, our results provide empirical evidence that integrating wood anatomical and physiological traits facilitates the understanding of resilience mechanisms that treeline forests develop in the face of increasing drought stress. [ABSTRACT FROM AUTHOR]

Southern Madagascar experienced a prolonged drought over the last five years, but whether these conditions are a manifestation of global climate change has been unclear. Here, we document trends beginning as early as 1980 towards a later rainy-season onset across three distinct remotely sensed indicators: precipitation, soil moisture, and vegetation greenness. All three indicators closely covary, particularly over the last decade when satellite observational resolution and accuracy is greatest. Furthermore, observed soil moisture trends early in the rainy season agree with the mean from CMIP6 historical and SSP5-8.5 simulations, but are distinct from pre-industrial control simulations, implicating anthropogenic changes in radiative forcing as the source of the trends. Physically, these models simulate a poleward migration of the mid-latitude jet that leads to a delay in the seasonal steering of storm tracks over Southern Madagascar. Soil moisture trends driven by anthropogenic forcing made the recent drought significantly more likely over 2017–2022 (p < 0.01), and such droughts are expected to become increasingly likely over this century. These results indicate that, although Madagascar has not substantially contributed to global greenhouse gas emissions, farmers in Southern Madagascar will need to adapt to drier conditions early in the rainy season as a consequence of global climate change. [ABSTRACT FROM AUTHOR]

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The future state of drought in China under climate change remains uncertain. This study investigates drought events, focusing on the region of China, using simulations from five global climate models (GCMs) under three Shared Socioeconomic Pathways (SSP1-2.6, SSP3-7.0, and SSP5-8.5) participating in the Inter-Sectoral Impact Model Intercomparison Project (ISIMIP3b). The daily Standardized Precipitation Evapotranspiration Index (SPEI) is employed to analyze drought severity, duration, and frequency over three future periods. Evaluation of the GCMs' simulations against observational data indicates their effectiveness in capturing historical climatic change across China. The rapid increase in CO2 concentration under high-emission scenarios in the mid- and late-future century (2040–2070 and 2071–2100) substantially influences vegetation behavior via regulation on leaf stomata and canopy structure. This regulation decelerates the increase in potential evapotranspiration, thereby mitigating the sharp rise in future drought occurrences in China. These findings offer valuable insights for policymakers and stakeholders to develop strategies and measures for mitigating and adapting to future drought conditions in China. [ABSTRACT FROM AUTHOR]

Climate change is anticipated to lead to an increase in the occurrence and intensity of drought and fluctuations in insect cycles that will challenge modern pasture systems. Feeding by root aphids such as Aploneura lentisci Pass. can be a significant challenge to pastures. These below-ground living aphids are commonly found in New Zealand and Australia, feeding year-round on the roots of graminaceous plants such as perennial ryegrass (Lolium perenne L.). Some strains of the fungal endophyte Epichloë festucae var. lolii in perennial ryegrass can provide protection against root aphids and greater resilience under drought, contributing to higher persistency and growth than endophyte-free plants. However, the interaction between insect pressure and drought is not understood. This study examined the effect of drought on root aphid populations and plant performance in perennial ryegrass plants relative to endophyte status (±) and endophyte strain (AR37, NZCT) in a glasshouse experiment. Plants were cloned across the drought and well-watered treatments, and half of the plants were inoculated with root aphids, whilst half of the plants were treated with insecticide. Endophyte infection with strain NZCT and AR37 reduced root aphid numbers. Aphid populations were significantly higher in drought-stressed than in well-watered plants in both endophyte-infected and endophyte-free treatments. Under drought conditions, root aphid populations were increased 4-fold in NZCT and 8-fold in AR37 and endophyte-free plants in comparison with their well-watered counterparts. Root aphids reduced shoot dry weight by 16% in drought-exposed and 26% in well-watered plants in comparison with their insecticide-treated counterparts whilst reducing root biomass by 49%. Our results suggest that root aphids are likely able to exploit the higher availability of amino acids in the plant sap of drought-exposed plants. This study provides evidence that climate change-mediated impacts of root aphids could reduce production in perennial ryegrass-dominant pastures. However, field trials would be necessary to determine whether this effect is seen in situ, where numerous additional factors will be operating at the same time. [ABSTRACT FROM AUTHOR]

The main objective of this research is to evaluate the effects of climate change first on precipitation and temperature, and then on the runoff characteristics of two tropical watersheds located in Senegal and Guinea-Bissau. To achieve this, eighteen General Circulation Models (GCMs) were selected to measure various climate change scenarios under the Shared Socioeconomic Pathways (SSP) SSP1-2.6 and SSP5-8.5, using the reference period of 1985–2014. The GR2M hydrological model was employed to replicate past monthly surface runoff patterns for the Casamance and Kayanga-Géva watersheds. After calibrating and validating the GR2M model, the researchers simulated the predictable effect of climate change on the flow for the near future (2021–2040), medium future (2041–2060), and distant future (2081–2100) for each watershed, using the GCM multi-model ensemble mean. The quantile method was used to correct bias in temperature and precipitation data. The results of bias correction give a correlation coefficient greater than 0.9% for temperatures and 0,6% precipitation between the outputs of the multi-model ensemble and observations used. The results indicate also that all watersheds are expected to experience drier conditions in the near-future, mid-future, and far-future periods under both the SSP1-2.6 and SSP5-8.5 scenarios. Furthermore, the predictable temperature trends consistently show a warmer situation with growing radiative making in the future times. However, the primary factor influencing changes in flow for all watersheds is the projected precipitation changes. The anticipated drier conditions in the near-future, mid-future, and far-future horizons under both scenarios would lead to significantly reduced runoff volumes at the beginning and middle of the rainy season. Consequently, the projected seasonal changes in river flow for all catchments (e.g., under SSP5-8.5 scenario, a decline of -34.47%, -56.01%, and -68.01% was noted, respectively, for the horizons 2050, 2070, and 2090 for the Casamance basin) could lead to new frequent occurrences of drought and water scarcity associated with past hydrological regimes. These scenarios enhance the necessity of improving water management, water prizing, and water recycling policies, to ensure water supply and to reduce tensions among regions and countries. [ABSTRACT FROM AUTHOR]

This study examines gender vulnerabilities and responsive strategies to climate change, comparing evidences from Kwara and Nassarawa States in Nigeria. Changes in climate parameters, gender-based perceptions of climate, as well as gender-based response and adaptation practices were assessed in accordance with specific research objectives. A total of 200 participants were surveyed through a mixed method approach using 41 years of climate data. Semi-structured questionnaires were administered equally in the two States and 52 in-depth interviews were conducted within male and female farmers that were 40 years and above age using a purposive sampling method. Results from Nassarawa State showed a downward trend in rainfall and an upward trend in both minimum and maximum temperatures. The farmers perceived climate change differently, with observed changes in climate variables: temperature and precipitation, resulting in extreme floods, drought, and rainfall onset and leading to varying adaptation practices. The study concluded that gender plays a significant role in the adoption of adaptation practices in the agricultural sector and that males often have more access to resources and decision-making power in farming as the heads of households. There is a need for better gender-sensitive approaches to adaptation planning and implementation to ensure that both men and women have equal opportunities to benefit from adaptation options in agriculture. [ABSTRACT FROM AUTHOR]

The dual crises of COVID-19 and climate change are impacting the lives of adolescents and young people as they transition to adulthood in an uncertain world, yet they are often excluded from research and political discourse. We surveyed young people about their needs and experiences, critical to engaging them and designing effective programs and policies to address these intersecting harms. The 2022 round of a national online survey through the Violence Outcomes in COVID-19 Epoch (VoCes) Study surveyed 152,088 Mexican youth (15–24 years). Logistic regressions were implemented to identify characteristics associated with four climate responses (economic, work-related, receiving government support, or social network support). Overall, 8.1% of participants experienced a recent climate hazard, with major impacts including housing damage from floods, and crop/livestock losses from drought. Participants who experienced a climate hazard were more likely to have experienced a pandemic-related harm, suggesting a dual impact. Poor youth were more likely to report economic losses from both the pandemic and a climate event but least likely to receive government support. Economic effects from the pandemic are exacerbating climate-related harms, unequally threatening the poorest youth. Engaging young people in decision-making and supporting the most vulnerable youth is critical for the next generation to thrive. [ABSTRACT FROM AUTHOR]