Drought Events Research Articles

Does drought increase intimate partner violence? Evidence from India

India has a high prevalence of intimate partner violence (IPV) against women. IPV has been observed to increase during natural disasters. Many studies have attempted to unravel the effect of drought on IPV; however, the evidence remains mixed. There is a gap in such studies in the Indian context, and this study seeks to fill this gap. We used data from the National Family Health Survey-4 (NFHS-4) (2015 – 2016) and NFHS-5 (2019 – 2021) to examine the effect of drought caused by the failure of the northeastern monsoon (NEM) in 2016 – 2018. Our analysis included data from 19 states and Union Territories of India (N = 34,590) in a difference-in-differences setup to evaluate the effect of the NEM drought on IPV. Exposure to the NEM drought was positively associated with physical violence (PV) and emotional violence, with results significant at the 95% and 99% confidence levels, respectively. A subsample analysis of rural and urban populations revealed that drought is significantly associated with an increase in sexual violence in urban areas, whereas it correlates with PV in rural areas. Additionally, exposure to drought is linked to a considerable rise in the controlling behavior of partners, for example, “He (is/was) jealous or angry if you (talk/talked) to other men,” “he (does/did) not permit you to meet your female friends).” These findings call for a two-fold policy action: providing support in the form of wage employment programs, subsidies, and other financial assistance during drought periods to help households cope with financial stress and implementing awareness programs aimed at changing partners’ mindsets, thereby reducing controlling behaviors in marriages.

Disentangling effects of droughts and heatwaves on alpine periphyton communities: A mesocosm experiment

AbstractThe accelerating rate of global climate change at higher elevations and latitudes is increasing the potential for extreme climatic events. Here, a knowledge gap exists in how the order of exposure to, and duration of droughts and heatwaves affect their cumulative impact on aquatic communities. We tested experimentally for the legacy effects of simultaneous vs. sequential exposures to drought and heatwave on sediment‐dwelling algal communities (epipelon) from small fishless alpine lakes. In both simultaneous, and sequential exposure treatments involving drought followed by a heatwave, the negative effect of drought masked the effects of warming on chlorophyll‐inferred algal biomass and taxonomic composition. Reversal of order of exposure (i.e., heatwave followed by drought) lowered their cumulative effect on community structure. These findings highlight the potential for drought events to dominate over heatwaves in altering shallow littoral ecosystems at high elevations under a rapidly warming climate.

Phylogenomic analysis of glutamine synthetase gene family in Helianthus annuus L.

Glutamine synthetase is one of the predominant enzymes in nitrogen metabolism. In developing leaves, glutamine is mainly produced in chloroplasts by the activity of the GS2 isoenzyme. It catalyzes glutamine synthesis from glutamate and ammonia in an ATP-dependent reaction. The genes encoding glutamine synthetase play a crucial role in ammonia and glutamate detoxification, acid-base homeostasis, cell signaling, and cell proliferation. The gene family responsible for producing glutamine synthetase has been previously documented in model plants like Arabidopsis. Nevertheless, there has been no exploration into its existence and attributes in oilseed crops like sunflower (Helianthus annuus L.). This study thoroughly analyzes, gene structure, conserved motifs, chromosomal location, phylogenetic relationships, and expression patterns to identify the glutamine synthetase genes in H. annuus. Our findings unveiled 19 genes encoding glutamine synthetase within the H. annuus genome. These genes were distributed across 11 chromosomes of H. annuus. Furthermore, we examined the expression patterns of all the HaGS genes using RNA-seq datasets, specifically focusing on their response to biotic and abiotic stress conditions. Under biotic stress, H. annuus expresses genes for mycorrhizal fungi named Rhizoglomus irregulare at four days post inflorescence (dpi) and 16 dpi. Under abiotic stress, the effect of drought and hormones was investigated. In drought, one gene, HaGS6D, showed the highest expression in the leaf. Meanwhile, in roots, gene HaGS7B showed the highest expression. Under hormonal stress, the effects of auxin, brassinosteroid, and cytokinin were studied on the leaf. For auxin, the gene HaGS7C showed the highest expression. For brassinosteroid, the gene HaGS7D showed the highest expression; for cytokinin, the gene HaGS6E showed the highest expression. Thus, these findings can significantly contribute to our understanding of the arrangement of glutamine synthetase genes in H. annuus and offer valuable insights for developing of drought-resistant cultivars of this species.

Integrating remote sensing modeling for drought assessment and vegetation monitoring in El Tarf, Algeria: a 40-year analysis

The escalating frequency and intensity of drought events, exacerbated by anthropogenic climate change, present critical challenges to hydrological resources, ecosystem resilience, and agricultural productivity. In North Africa, and specifically Algeria, comprehending the spatiotemporal patterns of drought is essential for sustainable water resource management and ecological conservation. This investigation focuses on the El Tarf region, located in northeastern Algeria, recognized for its ecological diversity and agricultural relevance. Employing a synergistic methodology, this study integrates the Standardized Precipitation Evapotranspiration Index (SPEI) for long-term drought severity evaluation with the Normalized Difference Vegetation Index (NDVI) to monitor vegetation phenology and health over time. Utilizing the computational power of Google Earth Engine, we process extensive temporal datasets of SPEI spanning from 1980 to 2023, complemented by high-resolution satellite imagery for NDVI computation. This comprehensive approach facilitates an in-depth analysis of drought dynamics, their severity, and impacts on vegetative cover in El Tarf over the past four decades. Our findings indicate significant long-term drought trends, with notable dry spells occurring between 1994 and 2003. Severe drought events were particularly pronounced in December 2022 (SPI = -2.50) and May 2002 (SPI = -2.2), correlating with substantial precipitation deficits. Although areas experiencing extreme drought have diminished, there has been an increase in moderate drought occurrences, suggesting an uptick in drought frequency, which poses risks to hydrological resources and ecosystem health. These observed patterns align with regional climate change projections, highlighting an urgent necessity for adaptive management strategies in agriculture and water resources.

Response mechanisms of Annual bluegrass (Poa annua) to cold, drought, combined stresses and recovery in morphology, photosynthesis, physiology and microstructure

Drought and cold stresses co-occur in nature, and significantly limited agricultural productivity in northwest China. Their effects on plant photosynthesis, physiology and biochemistry, and microstructure have been extensively studied, but their combined stress mechanisms remain unclear. Therefore, growth chamber experiments were conducted using the Annual bluegrass (Poa annua) with the ‘HZ’ and ‘ZQ’ germplasms, our goal was to clarify the responses of leaves to cold (C), drought (D), and combined (D&C) stresses in the morphology, photosynthesis, physiology and biochemistry, and microstructure. The results showed that three stress types significantly suppressed growth, reduced photosynthetic pigments, photosynthetic capacity, and photosynthetic enzyme activities, with ‘ZQ’ being more sensitive than ‘HZ’. C stress (12/36 h) improved chlorophyll fluorescence parameters in ‘HZ’ (except for photochemical quenching coefficient), while D and D&C stresses diminished these parameters of both germplasms. Under single and combined stresses, leaf thickness and cuticle thickness generally increased then decreased with stress duration, except for ‘ZQ’ under D stress. D stress increased reactive oxygen species, relative conductivity, malondialdehyde content and stomatal density, while inhibited stomatal size. Conversely, C stress exacerbated the negative effects of drought on these traits. The D&C stress enhanced antioxidant enzyme activity and proline content, which were similar to the responses to D stress, except for ‘ZQ’ under D&C stress. After 24 h of stress relief, the recoveries degree of most traits in plant under D and D&C stresses were similar, with ‘HZ’ recovering more than ‘ZQ’. This study indicated drought played a dominant role in combined stress. However, some unique responses could not be inferred from the superimposed effects of some single stresses.

Drought Tolerance in Plants: Physiological and Molecular Responses.

Drought, a significant environmental challenge, presents a substantial risk to worldwide agriculture and the security of food supplies. In response, plants can perceive stimuli from their environment and activate defense pathways via various modulating networks to cope with stress. Drought tolerance, a multifaceted attribute, can be dissected into distinct contributing mechanisms and factors. Osmotic stress, dehydration stress, dysfunction of plasma and endosome membranes, loss of cellular turgidity, inhibition of metabolite synthesis, cellular energy depletion, impaired chloroplast function, and oxidative stress are among the most critical consequences of drought on plant cells. Understanding the intricate interplay of these physiological and molecular responses provides insights into the adaptive strategies plants employ to navigate through drought stress. Plant cells express various mechanisms to withstand and reverse the cellular effects of drought stress. These mechanisms include osmotic adjustment to preserve cellular turgor, synthesis of protective proteins like dehydrins, and triggering antioxidant systems to counterbalance oxidative stress. A better understanding of drought tolerance is crucial for devising specific methods to improve crop resilience and promote sustainable agricultural practices in environments with limited water resources. This review explores the physiological and molecular responses employed by plants to address the challenges of drought stress.

A Multiscalar Standardized Vapor Pressure Deficit Index for Drought Monitoring and Impacts

ABSTRACTVapour pressure deficit (VPD) is a critical measure of the atmospheric demand for water and can be used to assess short‐term and seasonal drought. To provide for probabilistic comparisons of VPD across space and time, we develop a Standardized Vapor Pressure Deficit Index (SVPDI). Similar to the way that other standardised drought indices are used, SVPDI allows for the analysis and comparison of changes in VPD across regions with different base level VPD values. It also should be useful for analysing impacts on vegetation that has varying levels of adaptation to high VPD. We use 1‐, 3‐, 6‐ and 12‐month timescales for the development of SVPDI and show that the gamma distribution is superior to other zero‐limited probability distributions for analysing VPD and, therefore, for calculating SVPDI. Then, focusing on the short‐term variations at the 1‐ and 3‐month timescales, we show how SVPDI has changed globally from 1958 to 2023 and how those changes differ from those of the commonly used Standardized Precipitation Evaporation Index (SPEI). We find that SVPDI shows more widespread drying conditions that also are larger in magnitude compared to those of SPEI. Although the two indices are moderately well correlated across the terrestrial surface, we discover that they are more decoupled in humid and arid regions compared to dry sub‐humid and semi‐arid regions. Using four locations that have recently experienced severe drought, we find that SVPDI generally showed longer drought duration and more severe drought events in the last decade when compared to SPEI.

Investigating the influence of selenium and epibrassinolide on antioxidant activity, proline accumulation, and protein expression profiles in wheat plants experiencing heat and drought stress.

In the current investigation, the combination of selenium (Se) and epibrassinolide (EBL) exhibited a promising alleviative response against the concurrent stress of heat and drought in wheat plants. The compromised growth and photosynthetic performance of wheat plants under the combined stress of heat and drought were substantially improved with the treatment involving Se and EBL. This improvement was facilitated through the expression of Q9FIE3 and O04939 proteins, along with enhanced antioxidant activities. The heightened levels of antioxidant enzymes and the accumulation of osmoprotectant proline helped mitigate the overaccumulation of reactive oxygen species (ROS), including electrolyte leakage, H2O2 accumulation, and lipid peroxidation, thus conferring tolerance against the combined stress of heat and drought. Studies have demonstrated that Se and EBL can assist wheat plants in recuperating from the adverse effects of heat and drought. As such, they are essential components of sustainable farming methods that aim to increase crop productivity.

Optimizing the Sweet Potato Supply Chain in Zimbabwe Using Discrete Event Simulation: A Focus on Production, Distribution, and Market Dynamics

This study leverages a Discrete Event Simulation (DES) model to optimize the sweet potato supply chain in Zimbabwe, focusing on production, distribution, and market dynamics under varying climate conditions. The integration of climate data into the simulation model reveals significant insights into the resilience of different sweet potato varieties, particularly highlighting the suitability of yellow-skinned sweet potatoes for harsh climates due to their high resilience and drought resistance. However, market preferences still favor white-skinned varieties despite their vulnerability to climate extremes. The DES model identifies key bottlenecks, particularly in cultivation and transportation, that hinder supply chain efficiency. To address these challenges, the study emphasizes the importance of targeted interventions, such as improving access to irrigation, strengthening pest management, and adopting community-based resource-sharing approaches. These strategies are critical for enhancing both the resilience and efficiency of the supply chain. Additionally, the study highlights the urgent need for adaptive strategies to mitigate the effects of drought on agricultural productivity, especially in regions that heavily rely on crops like sweet potatoes. Overall, this research offers strategic insights for policymakers and stakeholders aiming to improve food security and agricultural productivity in Zimbabwe, as well as in other countries with similar climate challenges.

Peanut-Colonized Piriformospora indica Enhanced Drought Tolerance by Modulating the Enzymes and Expression of Drought-Related Genes.

Peanut (Arachis hypogaea L.) is an important cash and oil seed crop, mostly distributed in arid and semi-arid areas. In recent years, due to the influence of atmospheric circulation anomalies and other factors, drought has become frequent and increasingly serious in China. This has posed serious challenges to peanut production. The objective of this study was to investigate the potential of the endophytic fungus Piriformospora indica to form a symbiotic relationship with peanut plants and to evaluate the drought tolerance of P. indica-colonized peanut plants subjected to a simulated drought stress treatment using 20% polyethylene glycol 6000 (PEG6000). The endophytic fungus P. indica affected the physiological characteristics of the host plant by colonizing the plant roots, thereby conferring greater resistance to drought stress. This fungus strongly colonized the roots of peanuts and was found to enhance root activity after 24 h of P. indica colonization under PEG6000. Catalase (CAT) and peroxidase (POD) activities were increased at 24 h in peanut leaves colonized with P. indica. Expression of drought-related genes, such as AhNCED1, AhP5CS, and DREB2A was upregulated at 24 h of P. indica colonization. In addition, after PEG6000 treatment, proline, soluble protein, and abscisic acid (ABA) concentrations in plants were increased, while the accumulation of malondialdehyde (MDA), and hydrogen peroxide (H2O2) was decreased in P. indica colonized peanut. In conclusion, P. indica mediated peanut plant protection against the detrimental effects of drought resulted from enhanced antioxidant enzyme activities, and the upregulated expression of drought-related genes for lower membrane damage.

Eolian-fluvial succession in the Early Cretaceous from the Ordos Basin

Cretaceous eolian deposits are widely developed in North China, among which the Lower Cretaceous eolian (erg) sedimentary strata in the Ordos Basin are the most representative. Many studies have been conducted on eolian deposits in the Ordos Basin, especially the Luohe Formation; however, there is a lack of systematic sedimentology research and the corresponding research on the evolution of sedimentary facies. Therefore, to explore the Mesozoic drought events and the systematic evolution of the sub-tropical erg zone, this study reports the fluvial–eolian sedimentary sequences of the Early Cretaceous Luohe and Yijinhuoluo Formations in the Ordos Basin. Spatially, through detailed sedimentary lithofacies and structural analysis of different outcrops, the combination law of sedimentary facies can be determined. Based on this, a three-dimensional sedimentary model of erg is reconstructed. The erg environment is divided into three sub-environments: erg margin, erg margin–centre transition and erg centre. According to the evolution of the sedimentary facies, the sedimentary evolution from the Latef Jurassic to the Early Cretaceous in the Ordos Basin is divided into five stages. The Ordos Basin has experienced the delta, erg formation, erg deposition, erg shrinkage and evaporating salt-lake stages. The vertical sedimentary evolution indicates climatic oscillation in North China from the Late Jurassic to the Early Cretaceous. Under the control of the sub-tropical high belt, the Ordos Basin experienced a hot and arid climate during the Cretaceous, forming a widely distributed erg belt in the region. During this period, a small-scale climate shock occurred under the hot and arid background, changing the sedimentary environment.

Evaluating Hydrologic Model Performance for Characterizing Streamflow Drought in the Conterminous United States

Hydrologic models are the primary tools that are used to simulate streamflow drought and assess impacts. However, there is little consensus about how to evaluate the performance of these models, especially as hydrologic modeling moves toward larger spatial domains. This paper presents a comprehensive multi-objective approach to systematically evaluating the critical features in streamflow drought simulations performed by two widely used hydrological models. The evaluation approach captures how well a model classifies observed periods of drought and non-drought, quantifies error components during periods of drought, and assesses the models’ simulations of drought severity, duration, and intensity. We apply this approach at 4662 U.S. Geological Survey streamflow gages covering a wide range of hydrologic conditions across the conterminous U.S. from 1985 to 2016 to evaluate streamflow drought using two national-scale hydrologic models: the National Water Model (NWM) and the National Hydrologic Model (NHM); therefore, a benchmark against which to evaluate additional models is provided. Using this approach, we find that generally the NWM better simulates the timing of flows during drought, while the NHM better simulates the magnitude of flows during drought. Both models performed better in wetter eastern regions than in drier western regions. Finally, each model showed increased error when simulating the most severe drought events.

A Copernicus-based evapotranspiration dataset at 100 m spatial resolution over four Mediterranean basins

Abstract. Evapotranspiration (ET) is responsible for regulating the hydrological cycle, with a relevant impact on air humidity and precipitation that is particularly important in the context of acute drought events in recent years. With the intensification of rainfall deficits and extreme heat events, the Mediterranean region requires regular monitoring to enhance water resource management. Even though remote sensing provides spatially continuous information for estimating ET on large scales, existing global products with spatial resolutions ≥ 0.5 km are insufficient for capturing spatial detail at a local level. In the framework of ESA's 4DMED-Hydrology project, we generate an ET dataset at both high spatial and high temporal resolutions using the Priestley–Taylor Two-Source Energy Balance (TSEB-PT) model driven by Copernicus satellite data. We build an automatic workflow to generate a 100 m ET product by combining data from Sentinel-2 (S2) MultiSpectral Instrument (MSI) and Sentinel-3 (S3) land surface temperature (LST) with ERA5 climate reanalysis derived within the period 2017–2021 over four Mediterranean basins in Italy, Spain, France, and Tunisia (Po, Ebro, Hérault, and Medjerda). First, original S2 data are pre-processed before deriving 100 m inputs for the ET estimation. Next, biophysical variables, like leaf area index and fractional vegetation cover, are generated, and then they are temporally composited within a 10 d window according to S3 acquisitions. Consequently, decadal S2 mosaics are used to derive the remaining TSEB-PT inputs. In parallel, we sharpen 1 km S3 by exploiting the dependency between coarse-resolution LST and 100 m S2 reflectances using a decision tree algorithm. Afterwards, climate forcings are utilized to model energy fluxes and then for daily ET retrieval. The daily ET composites demonstrate reasonable TSEB-PT estimates. Based on the validation results against eight eddy covariance (EC) towers between 2017 and 2021, the model predicts 100 m ET with an average RMSE of 1.38 mm d−1 and a Pearson coefficient equal to 0.60. Regardless of some constraints mostly related to the high complexity of EC sites, TSEB-PT can effectively estimate 100 m ET, which opens up new opportunities for monitoring the hydrological cycle on a regional scale. The full dataset is freely available at https://doi.org/10.48784/b90a02d6-5d13-4acd-b11c-99a0d381ca9a, https://doi.org/10.48784/fb631817-189f-4b57-af6a-38cef217bad3, https://doi.org/10.48784/70cd192c-0d46-4811-ad1d-51a09734a2e9, and https://doi.org/10.48784/7abdbd94-ddfe-48df-ab09-341ad2f52e47 for the Ebro, Hérault, Medjerda, and Po catchments, respectively (Bartkowiak et al., 2023a–d).

Drought-Induced Alterations in Carbon and Water Dynamics of Chinese Fir Plantations at the Trunk Wood Stage.

Over the past three decades, China has implemented extensive reforestation programs, primarily utilizing Chinese fir (Cunninghamia lanceolata (Lamb.) Hook) in southern China, to mitigate greenhouse gas emissions and counter extreme climate events. However, the effects of drought on the carbon sequestration capacity of these forests, particularly during the trunk wood stage, remain unclear. This study, conducted in Huitong, Hunan, China, from 2008 to 2013, employed the eddy covariance method to measure carbon dioxide (CO2) and water fluxes in Chinese fir forests, covering a severe drought year in 2011. The purpose was to elucidate the dynamics of carbon and water fluxes during a drought year and across multi-normal year averages. The results showed that changes in soil water content (-8.00%), precipitation (-18.45%), and relative humidity (-5.10%), decreases in air temperature (-0.09 °C) and soil temperature (-0.79 °C), and increases in vapor pressure deficit (19.18%) and net radiation (8.39%) were found in the drought year compared to the normal years. These changes in environmental factors led to considerable decreases in net ecosystem exchange (-40.00%), ecosystem respiration (-13.09%), and gross ecosystem productivity (-18.52%), evapotranspiration (-12.50%), and water use efficiency (-5.83%) in the studied forests in the drought year. In this study, the occurrence of seasonal drought due to uneven precipitation distribution led to a decrease in gross ecosystem productivity (GEP) and evapotranspiration (ET). However, the impact of drought on GEP was greater than its effect on ET, resulting in a reduced water use efficiency (WUE). This study emphasized the crucial role of water availability in determining forest productivity and suggested the need for adjusting vegetation management strategies under severe drought conditions. Our results contributed to improving management practices for Chinese fir plantations in response to changing climate conditions.

Analysis and Exploration of Carbon Emission Dataset using Machine Learning Techniques

One of the primary environmental climate issues in metropolitan cities is that most people are faced with low air quality. Climate variance is impacting the world, triggering drought, storms, and extreme weather events. The primary contributor to climate change is affected greenhouse carbon gas emissions, of which carbon dioxide (CO2) and carbon monoxide (CO) make up the majority. The carbon emissions are expected to rise steadily worldwide. Many factors, including the burning of fossil fuels in transportation and manufacturing sectors, cause climate variance. Fast urbanization has used a high rate of motor vehicles as compared to a rural area. In metropolitan cities across the world, automobiles are the primary cause of air pollution. The use rate of vehicles keeps increasing, and that results in traffic congestion. This work is focusing on collecting two real-time vehicle emission datasets from two different devices to predict and compare the emissions of different light-duty vehicles by using the machine learning techniques. This research also analyzes the Canadian government emission dataset It shows the results of emission by fuel type and vehicle model. It shows the comparison graph of, mean square error, root mean square error and accuracy comparison of different machine learning algorithms. The work suggests some policies for reducing the carbon emissions. Even the government can adapt certain policies for mitigating the carbon emissions of individual vehicles. In this research work issues for reducing the emission of individual vehicles have been addressed. This work helps the automobile sector to reduce the emission and play a part to save the environment.

Activity of photosynthetic pigments and the antioxidant system in sunflower under drought stress

Background. The study is of particular importance in view of the increasing pace of global climate aridization. The article highlights the results of an experiment on the effect of drought on the physiological status of seedlings of cv. ‘Poseidon 625’ representing an important food crop – sunflower (Helianthus annuus L.). Materials and methods. The experiment included a group of control samples grown with sufficient moisture and four impact groups subjected to osmotic stress. The intensity of accumulation of lipid peroxidation products (LPP) was measured by the reaction of malondialdehyde (MDA) with thiobarbeturic acid; catalase activity was assessed by a photocolorimetric method based on the interaction between hydrogen peroxide and potassium iodide; the content of pigments (Chl a, Chl b, Сar) was calculated spectrophotometrically in acetone extract. Results. The degree of POL accumulation in the impact groups of the experiment was found to be many times higher than the values in the control samples, which was confirmed by a rapid increase in the MDA concentration in response to a growing water shortage. The accumulation of oxygen free radicals triggered the mechanisms of antioxidant protection of seedlings by synthesizing catalase, the concentration of which increased proportionally to the accumulation of POL. At the same time, the rapid accumulation of POL in the absence of irrigation and under osmotic stress of 3 and 5 atm led to a suppression of low-molecular-weight components of protection (carotenoids) and activation of their synthesis only when critical values of osmotic stress were reached. Conclusion. As a result of the experiment, catalase was identified as the main component of antioxidant protection in sunflower seedlings. Due to the activation of its synthesis, the concentrations of Chl a and Chl b decreased, attesting to the activation of the mechanisms protecting the photosynthetic activity in seedlings, and their antioxidant status.

The Impact of Short-Term Drought on the Photosynthetic Characteristics and Yield of Peanuts Grown in Saline Alkali Soil

Peanuts grown in saline alkali soil are also subjected to drought stress caused by water scarcity. Therefore, we used HY25 (peanut variety) as an experimental material to investigate the effects of drought on the height of peanut main stems, length of the first lateral branch, leaf area per plant, SPAD value, net photosynthetic rate, and accumulation and distribution of photosynthetic products in saline alkali soil. The results showed that the combined stress of short-term drought and salt significantly reduced the main stem height, first lateral branch length, single plant leaf area, SPAD value, net photosynthetic rate (Pn), intercellular carbon dioxide concentration (Ci), and dry matter accumulation of peanuts, including a decrease in single plant pod yield, 100-pod weight, 100-kernel weight, and peanut yield. And the impact of drought stress on peanut yield varies at different growth stages. For example, under drought stress alone, the sensitive period is the 40th day after planting (40D) > 60th day after planting (60D) > 30th day after planting (30D). Short-term drought has the greatest impact on peanut yield at 40D, while in contrast, resuming watering after drought at 30D results in a slight but not significant increase in peanut yield in comparison with the control. Under the combined stress of drought and salt, the sensitive period of peanuts was 40D > 30D > 60D, and the single pod weight of peanuts was significantly reduced by 15.26% to 57.60% from the flowering stage to the pod stage under drought treatment compared to salt treatment, indicating a significant interaction between drought and salt stress, reducing the single leaf area and net photosynthetic rate of peanut leaves, ultimately leading to a decrease in peanut yield. Therefore, when planting peanuts in saline alkali soil, drought should be avoided, especially early drought, in order to prevent the combined effects of drought and salt stress from harming peanut yield.

A parsimonious model for springs discharge reconstruction and forecast for drought management: Lessons from a case study in Central Italy

Study regionKarst springs located in Central Apennine ridge (Central Italy), in the Tiber River basin. Study focusThe assessment of water availability is a key issue in a water supply system because of increasing drought and water scarcity events. Analysing and predicting the dynamic behaviour of groundwater resources is challenging to conceptualize and model, especially in poorly-monitored systems. A parsimonious model based on linear regression between the monthly spring discharge time series and Standardized Precipitation Index is proposed. The model is conceived for management purposes and suitable for users with a limited background in modelling techniques, who can take advantage from an initial knowledge of the aquifers hydrological regime. New hydrological insights for the regionThe model developed for long-term monitored springs is used to reconstruct the historical groundwater hydrographs and to make predictions for poorly-monitored springs with similar properties, exploiting the “similarity principle”. Results highlight the notable performance of this approach, which represents a useful tool for overcoming the limitations in spring discharge monitoring networks. Moreover, the tool is used to test forecast performance enabling water managers to develop a monthly early-warning system fostering a sustainable water resource exploitation and limiting the critical issues of the water supply system, especially during drought periods. Results are discussed from the perspective of the water utilities entrusted to manage their resources in the study region.

Naming droughts: Historical perspectives on the scientific coining of “the Tinderbox Drought”

Most droughts go unnamed. At the time they are happening, they are generally referred to simply as “the drought.” After the fact, they are typically designated by a year or run of years rather than by a name: 1927–29, for instance. But in recent decades, proper names have increasingly been bestowed on droughts in southeast Australia in an informal although widely accepted practice. Examples include the Federation Drought, the World War II Drought, the Millennium Drought and, most recently, the Tinderbox Drought. This paper positions the practice of naming droughts within a longer history of naming weather extremes. It examines the implications of the naming practice for the investigation of droughts as complex objects of interdisciplinary knowledge that call for analysis from across the sciences, social sciences and humanities. And it considers the qualities and meanings attributed to the drought of 2017-19 by the name “Tinderbox.” Using the word “tinderbox” to describe environmental conditions has been criticised for naturalizing landscape flammability and so effacing human agency. But in fact the name “Tinderbox Drought” potentially enacts a semantic reversal that allows human-caused climate change to be reassociated discursively with recent and future drought events.

Community structure of tropics emerging from spatio-temporal variations in the Intertropical Convergence Zone dynamics

The Intertropical Convergence Zone (ITCZ) is a narrow tropical belt of deep convective clouds, intense precipitation, and monsoon circulations encircling the Earth. Complex interactions between the ITCZ and local geophysical dynamics result in high climate variability, making weather forecasting and prediction of extreme rainfall or drought events challenging. We unravel the complex spatio-temporal dynamics of the ITCZ and the resulting teleconnection patterns via a novel tropical climate classification achieved using complex network analysis and community detection. We reduce the high-dimensional complex ITCZ dynamics into a simple yet insightful community structure that classifies the tropics into seven regions representing distinct ITCZ dynamics. The two largest communities, encompassing landmasses over the Northern and Southern hemispheres, are associated with coherent seasonal ITCZ dynamics and have significant long-range connections. Temporal analysis of the community structure highlights that the tropical Pacific and Atlantic Oceans communities exhibit substantial variation on multidecadal scales. Further, these communities exhibit incoherent dynamics due to atmosphere-ocean interactions driven by equatorial and coastal oceanic upwelling.