Drought-affected Regions Research Articles

Groundwater exploration using self potential and resistivity geoelectrical method as drought disaster mitigation at bukit intan sub-district, Pangkalpinang

Abstract Pangkalpinang City in Bangka Belitung Islands province faces a seasonal water crisis due to its location outside the island’s groundwater basin. This study focuses on assessing groundwater potential in the Bukit Intan sub-district to support drought mitigation efforts. Using a combination of self-potential (SP) and geoelectrical resistivity methods, groundwater flow and aquifer depth were analyzed. Field data were collected across multiple tracks, with SP measurements revealing areas of potential groundwater movement, while resistivity profiles indicated aquifer presence at depths of 3-30 meters. Results suggest that groundwater potential is concentrated in certain recharge zones, highlighting areas suitable for targeted extraction and the establishment of boreholes. These aquifers exhibit seasonal fluctuations in groundwater levels, whereas the confined zones are located at greater depths and are more isolated, likely due to the presence of resistive layers that restrict flow. This assessment provides crucial insights for improving groundwater management in drought-affected regions of Pangkalpinang City.

Assessing the stability of terrestrial water storage to drought based on CMIP6 forcing scenarios

Assessing the stability of terrestrial water storage (TWS) under drought conditions is critical for the sustainable development of water resources. In this study, we integrated surface temperature (ST), leaf area index (LAI), and precipitation (P) data from five different scenarios (History, SSP1-2.6, SSP2-4.5, SSP3-7.0, and SSP5-8.5) of the Coupled Model Intercomparison Project Phase 6 (CMIP6) to develop a standardized temperature vegetation precipitation index (STVPI). The index was then utilized to monitor global drought conditions and investigate the stability of TWS to drought disaster. The results showed that STVPI can not only monitor meteorological drought, but also has a remarkable sensitivity and applicability to drought caused by sparse vegetation. Notably, 21.16% of the global land area will have a drought trend under the SSP1-2.6 scenario, while it will rise to 35.81% under the SSP5-8.5 scenario, which underscored the potential for an expansion of drought-affected regions worldwide as a result of ongoing global warming and escalating emissions. In addition, the results also found that the warm temperate and tropical regions at lower elevations have an advantage in maintaining the stability of TWS. Unfortunately, the stability of TWS to drought will decline in the western Sahara Desert, central China and northern United States in the future, where will face a serious water crisis. The research framework provides an important reference for deeply evaluating and scientifically allocating water resources under climate change.

Exploring factors affecting psychological resilience of farmers living in drought-affected regions in Iran: a qualitative study.

Drought, a prevalent consequence of climate change, significantly impacts mental health among farmers. Enhancing psychological resilience is crucial to mitigating these effects. This study aims to explore the concept and factors affecting the psychological resilience of farmers living in drought-affected regions in Iran. This study utilized a conventional qualitative content analysis method. Twenty-six participants, divided into two groups of experts and farmers, were selected through purposive sampling. Data collection was conducted via in-depth semi-structured interviews. The study adhered to the Consolidated Criteria for Reporting Qualitative Research (COREQ) checklist and was carried out between June 2023 and February 2024. The factors affecting the psychological resilience of farmers living in drought-affected regions were categorized into two main categories with nine subcategories. The first category, environmental factors, included economic factors, socio-cultural factors, drought adaptation methods, government policies, and infrastructural factors. The second category, intra-individual factors, comprised personal characteristics, health factors, psychological factors, and perception and knowledge. The study revealed that both environmental and intra-individual factors influence the psychological resilience of farmers during droughts. It is recommended to implement intervention strategies, such as providing training and education on drought adaptation methods and managing agricultural and healthcare expenses. Further research is needed to expand this concept to various disasters and occupational groups in future studies.

Exploring household water conservation methods in rural South Africa: a case of the Mbhashe and Mnquma local municipalities

Amidst the persistent drought disaster declared in 2015, the Amathole District Municipality grapples with severe water scarcity issues, particularly affecting local municipalities such as Mbhashe and Mnquma. Consequently, households in these areas confront the challenges of unreliable and contaminated water sources, prompting them to adopt water conservation measures to mitigate shortages. This study investigates the efficacy of water conservation methods among rural households in these drought-affected regions. It identifies associated challenges and potential interventions to ensure access to clean and dependable water. Employing a mixed methods approach, the study examines household water conservation practices through narrative analysis and descriptive statistics of survey data. Findings reveal that storing water in drums, containers, and tanks is the most prevalent conservation method, alongside measures like greywater reuse, lifestyle adjustments, and rainwater harvesting. With financial constraints and infrastructural limitations hindering broader adoption, the study found water conservation to be a challenge among the households as a minority (7.8%) of respondents adopted multiple water conservation strategies. In comparison, most respondents (73.6%) could only afford to practice one water conservation strategy at a time, and others (18.6%) had no conservation strategies. Drought conditions, lack of infrastructure, poverty, and attitudinal factors are primary barriers to effective water conservation. The study underscores the need for municipal-level initiatives to enhance water sources and advocates for increased investment in education, awareness campaigns, and policy interventions to address rural communities’ water scarcity challenges.

Performance evaluation and multivariate analysis of maize accessions against drought stress in Lamjung district, Nepal

The selection of drought-tolerant genotypes from the existing gene pool is a preliminary step for breeding for drought tolerance. Research efforts aimed at exploring the ability of crops to withstand drought stress have not yet touched the realm of reproductive drought performance of local genotypes. To examine how local crop accessions demonstrate varying reproductive performance under drought conditions, twenty accessions of maize (Zea mays L.) were evaluated for six quantitative traits in a two-factor factorial completely randomized design with two replications between February to June of 2023. All the traits under study showed significant differences among the genotypes (p < 0.05). Owing to their grain yield, ear weight, and hundred grain weight, accessions NGRC05592, NGRC05582, NGRC05564, NGRC05565, NGRC05571, and NGRC05569 performed better under drought condition than other tested accessions. Accession NGRC05592 showed the highest yield under drought condition, whereas, NGRC05573 and NGRC05576 showed poor performance. GGE Biplot analysis for grain yield revealed that NGRC05571 and NGRC05592 had the highest mean yield, with the accession NGRC05592 standing out as the stable variety under changing soil moisture levels and performing best among all the tested accessions under drought condition. The possibility of accession NGRC05592 being used as a potential genetic resource for drought breeding programs has been observed, but further studies aiming at its stability under field conditions in diverse agro-climatic regions across different years are encouraged to assure its prospect for developing cultivars suited to drought-affected regions.

Assessing drought tolerance in advance wheat genotypes using stress tolerance indices

Wheat, an important crop of Nepal, is significantly affected by drought, leading to severe yield losses. Thus, an experiment was conducted to assess effect of drought on wheat traits and to identify drought resilient genotypes comparing stress tolerance indices. Altogether seventy-two genotypes including checks were evaluated under drought and non-stress condition in an alpha-lattice design with two replications at the research block of National Rice Research Program, Hardinath, Nepal during winter of 2019/20. Analysis of variance revealed significant genotypic differences (p&lt;0.01) in traits such as days to heading, anthesis, and maturity, plant height, flag leaf area, spike length, grains per spike, 1000-grain weight, and grain yield under both conditions. The combined analysis of variance showed that genotype, environment, and their interaction significantly influenced most traits. The environment was the dominant factor, accounting for 86.2% of the variation in grain yield, followed by genotype (9.5%) and genotype-environment interaction (4.3%). Among the nine quantitative traits assessed, grain yield was most severely affected due to drought, experiencing a substantial reduction of 63%. To assess drought tolerance, six indices (TOL, SSI, MP, GMP, HMP, and STI) were calculated based on grain yield data. Most indices identified genotypes NL1373, NL1308, NL1407, BL4868, and BL4947 as highly drought-tolerant. Among the indices, MP, STI, and GMP were the most reliable for measuring stress tolerance due to their strong positive correlation with yield under both conditions. These identified genotypes are promising candidates for breeding programs aimed at developing drought-resilient wheat varieties, thereby enhancing food security in drought-affected regions.

Drought and radiation explain fluctuations in Amazon rainforest greenness during the 2015–2016 drought

Abstract. The 2015–2016 Amazon drought was characterized by below-average regional precipitation for an entire year, which distinguishes it from the dry-season-only droughts in 2005 and 2010. Studies of vegetation indices (VIs) derived from optical remote sensing over the Amazonian forests indicated three stages in canopy response during the 2015–2016 drought, with below-average greenness during the onset and end of the drought, and above-average greenness during the intervening months. To date, a satisfactory explanation for this broad temporal pattern has not been found. A better understanding of rainforest behaviors during this unusually long drought should help predict their response to future droughts. We hypothesized that negative VI anomalies could be caused by water and heat stress exceeding the tolerance ranges of the rainforest. To test our hypothesis, based on monthly observations of terrestrial water storage (TWS), land surface temperature (LST), and vapor pressure deficit (VPD) for January 2003 to December 2016, we proposed an approach to categorize regions into two groups: (1) those exceeding normal hydrological and thermal ranges and (2) those within normal ranges. Accordingly, regions exceeding normal ranges during different stages of the 2015–2016 event were delineated. The results showed a gradual southward shift in these regions: from the northeastern Amazon during August to October 2015 to the north–central part during November 2015 to February 2016 and finally to the southern Amazon in July 2016. Over these regions exceeding normal ranges during droughts, negative VI anomalies were expected, irrespective of radiation anomalies. Over the regions within normal ranges, VI anomalies were assumed to respond positively to radiation anomalies, as is expected under normal conditions. We found that our proposed approach can explain more than 70 % of the observed spatiotemporal patterns in VI anomalies during the 2015–2016 drought. These results suggest that our “exceeding normal ranges”-based approach combining (i) water storage, (ii) temperature, and (iii) atmospheric moisture demand drivers can reasonably identify the most likely drought-affected regions at monthly to seasonal timescales. Using observation-based hydrological and thermal condition thresholds can help with interpreting the response of the Amazon rainforest to future drought events.

Modern banking development during natural disasters: Evidence from the early 20th century China

How do commercial banks react to natural disasters? Using data for 375 droughts in 262 prefectures in China during 1906–1927, we find that drought-affected prefectures have more private bank inceptions than unaffected ones. The results remain robust to socioeconomic characteristics, foreign market exposure, and conditions of neighboring prefectures. This effect is driven by the prefectures with more agriculture-dependent enterprises, suggesting that banks meet local financial demand. On the other hand, new banks would enter less when the prefecture has more incumbent banks connected to drought-free areas. We argue that capital size and the network of capital reallocation are two advantages of banks coping with natural disasters over alternative financing vehicles such as pawn shops and foreign banks. In addition, the effect is greater among the prefectures practicing common law and with greater social capital, consistent with existing studies that bank credit supply depends on creditor rights protection. Finally, we show that drought-affected regions with more private bank inceptions have better development in agricultural businesses and social stability.

Drought Analysis in Right Bank Main Canal Command Area of Dharoi Reservoir using Meteorological and Remote Sensing Indices

Drought is characterized by a prolonged and abnormal lack of moisture, often stemming from insufficient or uneven distribution of precipitation, resulting in water shortages in streams or reservoirs, with detrimental impacts on both natural and socioeconomic systems. The paper focuses on the climatic drought patterns within the Right Bank Main Canal Command Area of Gujarat’s Dharoi Reservoir. To evaluate drought conditions, the study employs several indices including the Standardized Precipitation Index (SPI)and Normalized Difference Vegetation Index (NDVI). Daily rainfall data, obtained from IMD gridded data and extracted using ArcGIS software, is utilized to calculate SPI values at a three-month time scale. NDVI is determined using Landsat-8 OLI data spanning from 2013 to 2022 to analyze changes in agricultural vegetation. Comparisons among NDVI and SPI reveal that the year 2018 experienced significant rainfall deficits across the region, leading to severe water scarcity. This shortage impacted agricultural practices, evident in reduced crop cultivation areas as indicated by NDVI results and validated using the crop yield data for the time series. Specifically, the NDVI analysis highlights that 33.5% of the RBMC command area exhibited signs of dryness, with an additional 64.5% showing moderate dryness. The study endeavors to pinpoint drought-affected regions utilizing precipitation data, reservoir storage information, and remote sensing methodologies.

Construction of a High-Density Genetic Linkage Map Based on Bin Markers and Mapping of QTLs Associated with Fruit Size in Jujube (Ziziphus jujuba Mill.)

Jujube (Ziziphus jujuba Mill.) is a fruit tree that is gaining increasing importance in drought-affected regions worldwide. The fruit size is an important quantitative agronomic trait that affects not only the fruit yield and attractiveness but also consumer preference. Genetic enhancement of fruit appearance is a fundamental goal of jujube breeding programs. The genetic control of jujube fruit size traits is highly quantitative, and development of high-density genetic maps can facilitate fine mapping of quantitative trait loci (QTLs) and gene identification. However, studies regarding the construction of high-density molecular linkage maps and identification of quantitative trait loci (QTLs) targeting fruit size in jujube are limited. In this study, we performed whole-genome resequencing of the jujube cultivars “JMS2” and “Xing16” and their 165 F1 progenies to identify genome-wide single-nucleotide polymorphism (SNP) markers and constructed a high-density bin map of jujube that can be used to assist in the selection of multiple traits in jujube breeding. This analysis yielded a total of 116,312 SNPs and a genetic bin map of 2398 bin markers spanning 1074.33 cM with an average adjacent interval of 0.45 cM. A quantitative genetic analysis identified 15 QTLs related to fruit size and the observed phenotypic variation associated with a single QTL ranged from 9.5 to 13.3%. Through the screening of overlapping and stable QTL regions, we identified 113 candidate genes related to fruit size. These genes were ascertained to be involved in cell division, cell wall metabolism, synthesis of phytohormones (ABA, IAA, and auxin), and encoding of enzymes and transcription factors. These candidate genomic regions will facilitate marker-assisted breeding of fruits with different sizes and shapes and lay a foundation for future breeding and manipulation of fruit size and shape in jujube.

Spatiotemporal patterns and propagation mechanism of meteorological droughts over Yangtze River Basin and Pearl River Basin based on complex network theory

Investigating spatiotemporal pattern and propagation mechanism of meteorological drought is of great significance to develop early warning system for drought-affected regions and other drought types. In this study, the spatiotemporal characteristics and evolution trend of meteorological drought represented by the standardized precipitation evapotranspiration index (SPEI) during 2016–2021 across the Yangtze River basin (YZRB) and Pearl River basin (PRB) were analyzed. The drought spatial synchronization extent and propagation mechanisms (i.e., propagation source, sink, direction, strength and distance) were also investigated through constructing the undirected and directed complex networks, respectively. The results indicate that during 1961–2021, meteorological droughts in the middle and lower reaches of the YZRB and PRB present an alleviating trend, while droughts over their upper reaches that are relatively far from coastal regions are aggravated. The drought synchronization extents at the spatial scale are classified into seven communities, where the drought events within the same community are more likely to occur synchronously and their characteristics are more similar. Moreover, the drought propagation source regions are mainly distributed over the eastern coastal regions of the YZRB, the upper coastal regions of the PRB and the headwaters of the YZRB, from where droughts start to propagate along the WSW (or WNW) direction, NE direction and ESE direction to interior regions, respectively. The sink regions are mostly distributed in the YZRB and PRB middle reaches and the southwestern parts of the YZRB upper reaches. Meteorological drought events in most regions have a propagation distance of hundreds of kilometers. This study provides new tools and insights on drought propagation and prediction and can help policy-makers formulate advanced preventive measures.

Modulation of Antioxidant Defense Mechanisms and Morpho-Physiological Attributes of Wheat through Exogenous Application of Silicon and Melatonin under Water Deficit Conditions

Although the individual influences of silicon (Si) and melatonin (MT) have been widely studied under various abiotic stresses, little is known about their interaction under drought stress. In this study, an experiment in pots was carried out to investigate the potential of an individual or combined foliar application of silicon (Si) and melatonin (ML) (control (ck), water spray, 4.0 mM Si, 200 µM ML, and 4.0 mM Si + 200 µM ML) on wheat grown at two different water-holding capacity levels (80% well-water condition and 40% drought stress) in order to check of grain yield and some important physiological characteristics. Under drought stress conditions, grain yield and yield attributes, water content and photosynthetic efficiency of wheat crops were significantly decreased. Application of Si+ ML significantly improved leaf pigments (Chl a, Chl b and Chll a + b), leaf relative water content (RWC), proline, total soluble sugars, and total soluble protein. As well as, the activities of important antioxidant enzymes, including catalase (CAT), superoxide dismutase (SOD), peroxidase (POD) and ascorbate peroxidase (APX) were effectively boosted through the combined application of Si + ML. This improvement was correlated with an obvious decrease in the levels of MDA, H2O2, and electrolyte leakage and increased water use efficiency. Conclusively, the combination of Si + ML significantly enhanced the 20.21% yield and various morpho-physiological attributes of drought-stressed wheat plants and can be recommended as a promising treatment to enhance wheat productivity in drought-affected regions. Additionally, the results of this study may open up a whole new area of research opportunities at the transcriptional level to further understand the mechanisms underlying how Si + ML integrates and interacts with plants under drought stress.

Recent surge in cholera outbreaks globally during the COVID-19 pandemic era: a potential threat to the African continent and salient counteracting strategies.

Recent surge in cholera outbreaks globally during the COVID-19 pandemic era: a potential threat to the African continent and salient counteracting strategies.

An improved ‘assessment on comprehensive index’ for drought risk through an iterative transformation of ‘spatiotemporal vector’: a case study of Anhui Province, China

Abstract The unique climate, topography and soil conditions of Anhui Province in China are the main causes of drought, which is one of the limiting factors of economic and social development. Characterized by low data requirement, strong operability and flexibility, the conventional ‘assessment based on comprehensive index’ (ACI) is used to assess the drought risk, the index obtained by which can only represent the relative risk level among the objects and has no spatiotemporal characteristic. Therefore, a new method based on the iterative transformation of spatiotemporal vector (DRST) is proposed to solve this defect. The main conclusions are as follows: (1) The drought risk matrices obtained by DRS and DRT cannot quantify the drought risk level of subregions in each year absolutely. (2) The drought risk values obtained by DRST can be used to compare the drought risk from temporal and spatial dimensions at the same time, and both the drought-affected regions and the drought risk level are consistent with the statistical data. The new method expands the subsequent utilization space of the ‘assessment index’. For example, the allocation of drought-resistant resources (water resources, drought-resistant funds, etc.) can be determined according to these indexes.

Salt-responsive bermudagrass microRNAs and insights into light reaction photosynthetic performance.

Bermudagrass (Cynodon dactylon L.) is a warm-season grass with high drought and salt tolerance. However, its cultivation as a silage crop is limited by its lower forage value when compared to other C4 crops. Because of its high genetic variability in abiotic stress tolerance, bermudagrass-mediated genetic breeding offers significant promise for introducing alternative fodder crops in saline and drought-affected regions, and improved photosynthetic capacity is one way for increasing forage yield. Here, we used RNA sequencing to profile miRNAs in two bermudagrass genotypes with contrasting salt tolerance growing under saline conditions. Putatively, 536 miRNA variants were salt-inducible, with the majority being downregulated in salt-tolerant vs sensitive varieties. Also, seven miRNAs putatively targeted 6 genes which were significantly annotated to light reaction photosynthesis. Among the microRNAs, highly abundant miRNA171f in the salt tolerant regime targeted Pentatricopeptide repeat-containing protein and dehydrogenase family 3 member F1 both annotated to electron transport and Light harvesting protein complex 1 genes annotated to light photosynthetic reaction in salt tolerant regime vs salt sensitive counterparts. To facilitate genetic breeding for photosynthetic capacity, we overexpressed miR171f in Medicago tracantula which resulted in a substantial increase in the chlorophyll transient curve, electron transport rate, quantum yield of photosystem II non photochemical quenching, NADPH and biomass accumulation under saline conditions while its targets were downregulated. At ambient light level the electron transport was negatively correlated with all parameters while the NADPH was positively associated higher dry matter in mutants. These results demonstrate that miR171f improves photosynthetic performance and dry matter accumulation via transcriptional repression of genes in the electron transport pathway under saline conditions and thus a target for breeding.

Climate Change and Gender: Mapping Drought and Gender Gap in Literacy and Employment Sections in Iran between 2011 and 2016.

Background: Drought is one of the most frequent natural hazards in Iran. Gender analysis can highlight the different needs and capacities of men and women to manage drought hazards. Thus, the present study aimed to map drought and the gender gap in drought data based on the provincial zones in 2011 and 2016. Methods: This cross-sectional study was conducted in 2 stages establishing a database and spatial analysis. Data mapping was done based on provincial divisions, sex-disaggregated distribution of literacy, and employment rate as well as drought patterns in Iran in 2011 and 2016 using ArcGIS software. Descriptive statistics were applied to analyze and report the sex-disaggregated literacy and employment data. Results: About 80.73% and 75.27% of women and 80.89% and 74.74% of men experienced severe and very severe droughts in 2011 and 2016, respectively. Gender inequality in the aspects of literacy and employment in drought-affected regions was found in 2011 and 2016. Conclusion: Community-based planning and management in regions exposed to climate change are suggested for reducing the consequences of climatic disasters such as droughts. Women need to be empowered and trained for innovative livelihood activities in rural and urban areas in Iran and other developing countries affected by long-term droughts.

Multisource data-based integrated drought monitoring index: Model development and application

In this study, we proposed a new integrated remote sensing drought monitoring indices, i.e. Multiple Remote Sensing Drought Index integrated by Principal Component Analysis (PSDI), Multiple Remote Sensing Drought Index integrated by multiple linear regression (MRSDI) and Multiple Remote Sensing drought index integrated by gradient boosting method (GBMDI), based on the Precipitation Condition Index (PCI), Temperature Condition Index (TCI), Vegetation Condition Index (VCI), and Soil Moisture Condition Index (SMCI). The monitoring performance of PSDI, MRSDI and GBMDI was compared and verified based on the real-world observed droughts during 2002 to 2016. We also evidenced drought monitoring performance of the PSDI MRSDI and GBMDI by comparison between PSDI, MRSDI, GBMDI and SPEI, SPI and PDSI based on the in situ observed meteorological data. We found that the spatiotemporal characteristics of droughts monitored by the PSDI, MRSDI and GBMDI were generally in good agreement with those by the SPI and SPEI. The GBMDI performs better than PSDI and MRSDI in describing drought processes and spatial patterns of droughts of different drought intensities. Comparison between the real-world observed drought-affected croplands and those monitored by PSDI, MRSDI and GBMDI indicated better drought monitoring performance of GBMDI than PSDI and MRSDI in monitoring droughts across widespread drought-affected regions. Besides, the trend of GBMDI is in good agreement with standardized crop yield. Therefore GBMDI should be the first choice in drought monitoring practice. The GBMDI developed in this study can help to provide an alternative drought monitoring index for large-scale drought monitoring across China and also in other regions of the globe.

The contribution of community health systems to resilience: Case study of the response to the drought in Ethiopia.

BackgroundEthiopia’s exposure to the El Niño drought (2015-2016) resulted in high malnutrition, internally displaced people, and epidemics of communicable diseases, all of which strained the health system. The drought was especially challenging for mothers and children. We aimed to identify salient factors that can improve health system resilience by exploring the successes and challenges experienced by a community-based health system during the drought response.MethodsWe collected data via key informant interviews and focus group discussions to capture diverse perspectives across the health system (eg, international, national, district, facility, and community perspectives). Data were collected from communities in drought-affected regions of: 1) Somali, Sitti Zone, 2) Hawassa, Southern Nations, Nationalities, and Peoples’ Region (SNNPR), and 3) Tigray, Eastern Zone. Data were analysed using a deductive-inductive approach using thematic content analysis applied to a conceptual framework.ResultsA total of 94 participants were included (71 from the communities and 23 from other levels). Key themes included the importance of: 1) organized community groups linked to the health system, 2) an effective community health workforce within strong health systems, 3) adaptable human resource structures and service delivery models, 4) training and preparedness, and 5) strong government leadership with decentralized decision making.ConclusionsThe results of this study provide insights from across the health system into the successes and challenges of building resilience in community-based health systems in Ethiopia during the drought. As climate change exacerbates extreme weather events, further research is needed to understand the determinants of building resilience from a variety of shocks in multiple contexts, especially focusing on harnessing the power of communities as reservoirs of resilience.

Mapping actual evapotranspiration using Landsat for the conterminous United States: Google Earth Engine implementation and assessment of the SSEBop model

The estimation and mapping of actual evapotranspiration (ETa) is an active area of applied research in the fields of agriculture and water resources. Thermal remote sensing-based methods, using coarse resolution satellites, have been successful at estimating ETa over the conterminous United States (CONUS) and other regions of the world. In this study, we present CONUS-wide ETa from Landsat thermal imagery-using the Operational Simplified Surface Energy Balance (SSEBop) model in the Google Earth Engine (GEE) cloud computing platform. Over 150,000 Landsat satellite images were used to produce 10 years of annual ETa (2010–2019) at unprecedented scale. The accuracy assessment of the SSEBop results included point-based evaluation using monthly Eddy Covariance (EC) data from 25 AmeriFlux stations as well as basin-scale comparison with annual Water Balance ETa (WBET) for more than 1000 sub-basins. Evaluations using EC data showed generally mixed performance with weaker (R2 < 0.6) correlation on sparsely vegetated surfaces such as grasslands or woody savanna and stronger correlation (R2 > 0.7) over well-vegetated surfaces such as croplands and forests, but location-specific conditions rather than cover type were attributed to the variability in accuracy. Croplands performed best with R2 of 0.82, root mean square error of 29 mm/month, and average bias of 12%. The WBET evaluation indicated that the SSEBop model is strong in explaining the spatial variability (up to R2 > 0.90) of ETa across large basins, but it also identified broad hydro-climatic regions where the SSEBop ETa showed directional biases, requiring region-specific model parameter improvement and/or bias correction with an overall 7% bias nationwide. Annual ETa anomalies over the 10-year period captured widely reported drought-affected regions, for the most part, in different parts of the CONUS, indicating their potential applications for mapping regional- and field-scale drought and fire effects. Due to the coverage of the Landsat Path/Row system, the availability of cloud-free image pixels ranged from less than 12 (mountainous cloud-prone regions and U.S. Northeast) to more than 60 (U.S. Southwest) per year. However, this study reinforces a promising application of Landsat satellite data with cloud-computing for quick and efficient mapping of ETa for agricultural and water resources assessments at the field scale.

Parched and impatient: Political engagement after drought

How does local experience of climate change alter voters' policy preferences and voting decisions? After exposure to a climate disaster, voters may elect politicians prioritising robust disaster prevention policies, or conversely, immediate economic relief. In turn, elected representatives will either mitigate or exacerbate the severity of future climate events. In this study, I leverage a climate event with a high degree of local geographic variation – a pre-election drought in Australia – to see how it shaped political beliefs and behaviours in 2019. Using a longitudinal panel survey, I show that voters in drought-exposed areas increasingly prioritised individual economic security, rather than broader climate-mitigation policies. Moreover, I find that regional micro-parties in drought-affected regions gained vote share. In other words, voters at the front-lines of climate change sought out immediate and local economic relief. Unless local politicians can propose climate policies with short-term economic benefits, disasters may limit governments' capacities to pursue long-term climate resilience.