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Drought management is currently informed by a variety of approaches, mostly responding to drought crisis when it happens. Toward more effective and integrated drought management, we introduce a conceptual drought diagnosis framework inspired by diagnostic concepts from the field of medicine. This framework comprises five steps: 1. Initial diagnostic assessment; 2. Diagnostic testing; 3. Consultation; 4. Communication of the diagnosis; and 5. Treatment and prognosis. To illustrate the need for the proposed approach, four case studies of recently drought‐affected regions were selected: the city of Cape Town, the state of California, the Northeast region of Brazil, and the Horn of Africa. Contrasting elements for these cases include the geographic extent and political boundaries, climate, socio‐economics, and the relevance of different water resources (e.g., rainfall, reservoirs, and aquifers). For each case, we identified documented practices and policies and reflected on them in terms of drought misdiagnosis or incomplete diagnosis that have aggravated socio‐economic and environmental drought impacts. A common example is the preference for technical solutions (e.g., installing infrastructure to augment water supply), rather than measures that reduce vulnerability. Analysis of these four drought case studies confirmed the anticipated need for a comprehensive approach to drought diagnosis for more successful treatment and prevention of drought. Using an analogy with medical science can be helpful toward comprehensively diagnosing droughts for a variety of contexts and assessing the effectiveness of proposed interventions. This framework can help drought managers to be more proactive in enabling drought‐affected regions to become more drought resilient in the future. Plain Language Summary: Droughts are becoming more common around the world, are occurring in new areas, lasting longer, and are affecting more people. When drought hits, we often experience water shortages, which can affect agriculture leading to food shortages. Additional drought impacts on health, lifestyle, and ecosystems include drying rivers and lakes, dust storms, water use restrictions, a lack of snow, dying forests, and wildfires. In extreme cases, droughts cause famine, disease, and migration. The fact that such drought impacts regularly make the news shows how ineffectively we currently manage drought; because the common practice is to respond to drought crisis as it happens rather than preparing in advance. Considering drought as a health disorder, we can follow the process used in medicine to diagnose that disorder and prescribe treatment. We suggest using this approach would enable us to identify where and how a location is vulnerable to drought and work on treatments. We could improve the health of a location before drought hits, thus reducing drought impacts. We discuss four recent drought cases: the city of Cape Town, state of California, Northeast region of Brazil, and Horn of Africa, to illustrate how drought could be better dealt with using our proposed approach. Key Points: Analysis of recent droughts shows that drought diagnosis is often insufficient leading to unsuccessful strategies to deal with droughtDrought diagnosis can be improved by using an analogy with the medical diagnostic processThis emphasizes that the focus of a comprehensive drought diagnosis should be to prescribe treatment that reduces drought impacts [ABSTRACT FROM AUTHOR]

Understanding concurrent drought events in global main croplands is crucially important for food security, effective adaptation to climate change and human well‐being. Yet, there is a lack of comprehensive studies on concurrent drought probability changes among main crop production countries on a global scale, especially for the future. Here, we studied concurrent drought among 26 main crop production countries for the time period 1861–2099. During the historical period, probability of concurrent moderate and severe drought among the countries was relatively low, and the maximum concurrent moderate and severe drought probability will double and triple under RCP8.5 extreme climate, respectively. Concurrent probability of moderate and severe drought between China and United States of America, Brazil and Russia will be at least 6% and 5% under RCP8.5, respectively, compared with zero in the historical period. Limiting RCPs to RCP2.6 can decrease the concurrent probability of severe drought at least 2% (at least 3% for RCP8.5). Plain Language Summary: In the past over 100 years, the world had rarely experienced extreme drought events that occurred at the same time among major food producing countries. Yet, there is a lack of comprehensive studies on the changes of the concurrent drought probability among global main crop production countries, especially for the future. We studied the concurrent drought among 26 global main crop production countries for the time period 1861–2099. We find that the maximum concurrent probability of moderate and severe drought will double and triple, respectively, under the business as usual climate scenario. Concurrent probability of moderate and severe drought between China and United States of America, Brazil and Russia will be at least 6% and 5% under future business as usual climate, compared with zero in the historical period. Key Points: Maximum concurrent probability of moderate and severe drought will double and triple under RCP8.5, respectivelyConcurrent probability of moderate and severe drought between China and United States of America, Brazil and Russia will be at least 6% and 5% under RCP8.5Limiting RCPs to RCP2.6 can decrease the concurrent probability of severe drought at least 2% (at least 3% for RCP8.5) [ABSTRACT FROM AUTHOR]

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A significant fraction of Brazil's population has been exposed to drought in recent years, a situation that is expected to worsen in frequency and intensity due to climate change. This constitutes a current key environmental health concern, especially in densely urban areas such as several big cities and suburbs. For the first time, a comprehensive assessment of the short‐term drought effects on weekly non‐external, circulatory, and respiratory mortality was conducted in 13 major Brazilian macro‐urban areas across 2000–2019. We applied quasi‐Poisson regression models adjusted by temperature to explore the association between drought (defined by the Standardized Precipitation‐Evapotranspiration Index) and the different mortality causes by location, sex, and age groups. We next conducted multivariate meta‐analytical models separated by cause and population groups to pool individual estimates. Impact measures were expressed as the attributable fractions among the exposed population, from the relative risks (RRs). Overall, a positive association between drought exposure and mortality was evidenced in the total population, with RRs varying from 1.003 [95% CI: 0.999–1.007] to 1.010 [0.996–1.025] for non‐external mortality related to moderate and extreme drought conditions, from 1.002 [0.997–1.007] to 1.008 [0.991–1.026] for circulatory mortality, and from 1.004 [0.995–1.013] to 1.013 [0.983–1.044] for respiratory mortality. Females, children, and the elderly population were the most affected groups, for whom a robust positive association was found. The study also revealed high heterogeneity between locations. We suggest that policies and action plans should pay special attention to vulnerable populations to promote efficient measures to reduce vulnerability and risks associated with droughts. Plain Language Summary: Drought is a complex phenomenon that affects environmental and socioeconomic sectors, with important implications in public health. This phenomenon may impact different groups among the population unequally, but thus far, very few studies have explored the potential differences in drought effects on mortality in different population groups separated by sex and age. Thereby, further, and conclusive studies are required to get a deeper understanding of the populations at potential risk, especially considering the expected increase in frequency and intensity of drought events in several regions of the world such as Brazil due to climate change, posing a growing threat to health. In this study, we aimed to analyze for the first time the short‐term effects of different levels of drought severity on weekly no‐external, circulatory, and respiratory mortality in 13 major macro‐urban areas of Brazil across 2000–2019 in the total population, incorporating an assessment by sex and six age groups to know ultimately the structure of the population at risk. We found that overall, accounting for the 13 Brazilian urban areas, there were strong gender differences, with females being the most affected. Moreover, drought mostly influenced mortality in children and the elderly. We also found heterogeneity across urban locations. Key Points: Drought influenced positively non‐external, circulatory, and respiratory mortality in Brazilian urban areas in specific population groupsFemales, children, and the elderly were the populations more at riskDrought mostly affected mortality in those locations that suffered higher number and severity of drought conditions [ABSTRACT FROM AUTHOR]

We examine the effects of rainfall shocks on household work decisions in Brazil. We show that rural farming households increase labor supply in non‐agricultural sectors during drought episodes. An additional drought month per year is associated with greater likelihood of holding more than one job, lower share of agricultural employment, and more time spent performing a secondary job. Together, these findings suggest that households alter their labor decisions to mitigate the consequences of weather shocks. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Ecology is the property of Wiley-Blackwell 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.)

Using data from the Damage Assessment Reports from the Civil Defence, the current study investigates the relationship between the damage caused by natural disasters and local development at the municipality level in Ceará state, Brazil. The results show that a better urban and water supply infrastructure, a lower population density, and a higher proportion of own revenues relative to total revenues are associated with smaller disaster damage. However, economic development in terms of GDP per capita exhibits a convex relationship with the impact of natural disasters across municipalities, reflecting the potential decreasing returns of preventive investments due to the highly hazardous environment that involves municipalities. [ABSTRACT FROM AUTHOR]

In Northeast Brazil (NEB), severe droughts have high socioeconomic impacts. In this study, the spatial–temporal characteristics of drought were evaluated based on a new drought index at 4‐km spatial resolution, derived from regional empirical relationships between a remote sensing‐based index and rain‐gauge‐based standardized precipitation index (SPI), a well‐known drought meteorological index. This index was used to compare the spatial pattern of severe drought events (1982–1983, 1992–1993, 1997–1998, and 2012–2013) of the last 30 years. Strong El Niño related droughts were found to be generally spatially limited, affecting around 30% of NEB and concentrated in the northern part of the region, while 2012 drought, which was not El Niño related, was widespread, reaching 46% of NEB. These results stressed the importance of analyzing droughts at the subregion scale using data with higher spatial resolution. Statistically significant trends (p < 0.05) toward drier conditions detected in the SPI time‐series were linked to the tropical Atlantic Ocean warming trend, which result in an increased drought risk and social vulnerability in the region. [ABSTRACT FROM AUTHOR]

This work addresses the relationships between Land Use/Land Cover (LULC) and water quality in the Paraíba do Sul River (PSR), located in one of the most populated regions in Brazil. We conducted a water sampling program (analyzing nitrate, ammonium, phosphate, turbidity, total carbon, oxygen concentration, and conductivity) during a severe drought period from 2014 to 2016. The 210 samples were spaced about 5 km apart from headwaters to the Atlantic Ocean and taken over 63 d. We calculated a water quality index and applied a self-organizing map (SOM) to explore the relationship between LULC and water quality. There was a significant influence on water quality from the urban area's socioeconomic profile. This observation reflects the influence of cities with a high population density and a low economic condition, which leads to further degradation and erosion of the riverbanks. The most degraded reservoir of the PSR (Funil) partially buffers these effects by retaining deposited sediments and nutrient loads, leading to downstream water quality improvement. Better management practices of the riverbanks in the lower reach contribute to additional water quality improvements. Three major clusters identified using the SOM had completely different and explainable water quality patterns, suggesting an abrupt change in water quality due to human interventions. This information is crucial to improve management projects for the river at a watershed level, and with the expectation of future water shortages. [ABSTRACT FROM AUTHOR]

•Remote sensing data are a key tool to assess large forested areas, where limitations such as accessibility and lack of field measurements are prevalent. Here, we have analysed datasets from moderate resolution imaging spectroradiometer (MODIS) satellite measurements and field data to assess the impacts of the 2005 drought in Amazonia. •We combined vegetation indices (VI) and climatological variables to evaluate the spatiotemporal patterns associated with the 2005 drought, and explore the relationships between remotely-sensed indices and forest inventory data on tree mortality. •There were differences in results based on c4 and c5 MODIS products. C5 VI showed no spatial relationship with rainfall or aerosol optical depth; however, distinct regions responded significantly to the increased radiation in 2005. The increase in the Enhanced VI (EVI) during 2005 showed a significant positive relationship ( P < 0.07) with the increase of tree mortality. By contrast, the normalized difference water index (NDWI) exhibited a significant negative relationship ( P < 0.09) with tree mortality. •Previous studies have suggested that the increase in EVI during the 2005 drought was associated with a positive response of forest photosynthesis to changes in the radiation income. We discuss the evidence that this increase could be related to structural changes in the canopy. [ABSTRACT FROM AUTHOR]

Abstract Flooding and drought are important hydrological disturbances occurring in intermittent streams located in semiarid regions. The present study aims to analyse the effects of flood and drought on the diversity and stability of an intermittent stream fish community from the Brazilian semiarid region over the 1996 hydrological cycle. Fourteen fish collections were conducted during the rewetting, wet and drying phases, and 808 individuals were collected. Diversity was measured by using Simpson’s Index (S) and community stability was analysed by using the variation in the abundance, then tested by applying Kendall’s (W) test of concordance over the relative abundance rankings. This test supplies information about the stability of communities by means of the concordance of rankings. A community that is stable or near equilibrium has more constant rankings of its constituent species compared with a fluctuating one. The diversity increased progressively during the rewetting phase (S = 0.480–0.693; coefficient of variation = 0.131), reached its highest values during the wet phase (S = 0.745–0.861; coefficient of variation = 0.072), and remained high during the drying phase, with a lower oscillation than in the other phases (S = 0.699–0.801; coefficient of variation = 0.050). The abundance per collection varied significantly (Kruskal– Wallis 6.94, P = 0.031) throughout the hydrological phases. The stability of the community was higher during the rewetting (W = 0.58, P < 0.001) and drying (W = 0.86, P < 0.001) phases than during the wet phase (W = 0.45, P = 0.1818). In the Brazilian semiarid region, flooding disrupted the stability of the fish community studied and increased the diversity, whereas the absence of floods (expressed by the drying phase) caused a higher stability of the fish community and led to less variation in diversity. [ABSTRACT FROM AUTHOR]