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This chapter analyzes sustainable river management in the Murray–Darling Basin, where growing salinity problems and decreasing security of supply began to cause political conflict between and within the four states that share the catchment. The Murray–Darling Basin Authority has been responsible for coordinating the management of storage reservoirs, major infrastructure, and cross-border flows since 1917. In recent years, however, water needs of different activities are mediated through the dynamics of the market rather than the decisions of government officials. In many regions in the basin, however, water management is more complex now than it was only a few decades ago. The shortage of skilled personnel to manage Australia’s highly modified hydrological systems, which is already making itself felt, could well prove the greatest risk in the medium and longer term.
The Colorado is a river in transition – a newly “closed” basin where demands have exhausted reliable supplies. Decades of often short-sighted management decisions have contributed to the crisis environment that currently surrounds the Colorado River. Over the past fifteen years, however, stakeholders and managers have enacted significant changes to the rules and regulations governing the Colorado, and additional reforms remain close to enactment. Unlike the deal-making that characterized negotiations in the twentieth century, recent efforts focus primarily on strategies to promote coordinated management, reduce consumption, and restore a more holistic watershed perspective to a river that was legally apportioned long ago among a highly complex amalgam of jurisdictions and water users. In many respects, the river management system is a successful example of adaptation to changing social and hydrological conditions. Yet, it remains an open question whether the pace and scale of reform is sufficient to deal with the basin’s future.
The effects of the 4.2 kya climatic event on northern Mesopotamia have been the subject of significant scholarly debate, with the notion of a megadrought that forced local populations to migrate attracting particular attention. Here, the authors analyse stable carbon (δ13C) and nitrogen (δ15N) isotopes in human tooth and bone samples to assess trends in subsistence practice at three sites in Syria before, during and after the presumed megadrought event. Despite the proximity of the sites, isotopic differences between them are more significant than diachronic change. Combined with other archaeological evidence, these results indicate a continuity in subsistence patterns, with no indication of disruption associated with the 4.2 kya event.
This paper studies the effects of drought shocks in a vulnerable environment – the Brazilian Semi-Arid. We analyze the impact of drought shocks, measured as deviations from long-run historical averages, on agricultural outcomes in a region that suffers recurrently from drought. After controlling for municipality and year fixed effects, we use weather shocks to exactly identify outcomes. Our benchmark results show substantial effects on the loss of crop area and on the value of agricultural output, as well as on crop yields. As we investigate distributional effects, our results show that crops related to familiar agriculture suffer more from drought shocks. We follow our investigation by testing heterogeneity effects and show that adequate water provision and maintenance of forest cover help in reducing the impact of drought shocks.
To a God Unknown has typically been viewed as one of John Steinbeck’s most problematic novels, not least because of the its jarring mixture of realistic and fantastic elements. This chapter reevaluates Steinbeck’s early novel by placing it in the context of emergent ideas about race and climate in the American West. To a God Unknown is an experimental work that attempts to fuse realist and symbolic modes in ways parallel to the genre of magical realism, which first developed in post-Expressionist art of the 1920s. By exploring Steinbeck’s thinking during his composition of the novel, particularly his interest in “race psychopathology” and his reading in early climate science, we discover how Steinbeck’s magical realism is a pioneering attempt to understand and represent the aridity and drought that define the climate of the West and have profound implications for the kind of human society it can sustain. Through formal analysis in historical context, the chapter lays the groundwork for considerations of Steinbeck as a writer of the Anthropocene and of environmentalist critique.
Raised in the agriculturally rich Salinas Valley, Steinbeck was naturally fascinated by gardening, vegetables, and plant life in general. If Steinbeck’s experiments with animal consciousness are compromised by uncritical racial ideology, then his stories about plants have more radical implications. “The Chrysthanthemums” from The Long Valley explores the intimacy of the human-plant connection and imagines a form of human consciousness that verges on the passive receptivity of a plant-like existence as pure growth. Steinbeck’s approach to post-human subjectivity continues in “The White Quail,” which returns to interests in gardening and eugenics. Through its imagery, allusions, and theme of marriage, the story dismantles the assumptions of eugenics by questioning the symbolic identification suggesting that selective breeding of plants translated into possibilities for human betterment. A coda on The Grapes of Wrath and drought photography explores representations of human and vegetable reactions to drought to make clear the achievement and the limits of Steinbeck’s forays into alternate states of human consciousness in his stories.
Drought is a devastating factor for crop production worldwide. Therefore, an experiment was conducted to study genetics for some agro-physiological traits in cotton under drought stress. The 13 parental cotton genotypes along with their 30 F1 hybrids were planted under normal and drought conditions. The mean performance of the genotypes was assessed through principal component and heat map analyses. The principal component analyses revealed 53.99 and 53.15% in the first two principal components of variability for normal and drought conditions, respectively. Heat map analysis revealed that three cotton genotypes i.e. FH-207 × NS-131, FH-207 × KZ-191 and S-15 × AA-703 attained higher values for all the traits except for canopy temperature under drought conditions. These crosses may proliferate to further filial generations to identify transgressive segregates for drought tolerance. The heritable differences of F̅1 and mid-parent showed dominance and non-additive gene action under drought conditions. Heritable differences between F̅1 and P̅1 showed over dominance and partial dominance under drought conditions. Heritable differences between F̅1 and P̅2 indicated negative over dominance and partial dominance for all traits under drought conditions. Proline contents and the bolls per plant showed high heritability and genetic advance through additive gene action. Therefore, these two traits can be used as a means of selection in future breeding programmes of drought tolerance.
Historically, El Niño events have been associated with droughts and famines. Climate change will make extreme El Niño events more frequent and intense. In 2015–2016, one of the warmest El Niños on record helped trigger massive droughts across Ethiopia, Southern Africa, India, the Maritime Continent, Thailand, Latin America, and Brazil. Exceptionally warm ocean waters decimated fisheries and bleached coral reefs. In Ethiopia and southern Africa, 36 million people were pushed into near-famine conditions. Building on the author’s own research, this chapter examines how climate change has contributed to the ~+0.8°C increase in strong El Niños. In a world without climate change, such a +0.8°C increase would be possible but very unlikely. In a world with climate change, such a change would be very likely. Climate change made the 2015–2016 El Niño more extreme, contributing to Ethiopia’s and southern Africa’s extreme hunger and economic loss. Climate change is hurting people now. Climate change models predict that more extreme El Niños are likely over the next twenty years. The chapter contains a firsthand account from Prosper Chirara, a poor young man from Zimbabwe devastated by drought in 2015 and 2016.
In May 2016, the author traveled to Washington, DC to warn the food security community about a potential food crisis in East Africa if a 2016–2017 La Niña followed the 2015–2016 El Niño. This assertion, unfortunately, turned out true, and East Africa suffered a series of brutal back-to-back droughts in late 2016 and early 2017. Supporting this effective early warning was an understanding of how climate change is making La Niña events more extreme, and how climate change has contributed to a drying trend over eastern East Africa, placing millions of people in peril. This chapter uses personal accounts and research by the author to describe how climate change contributed to the March–May 2017 drought. La Niña events cool the equatorial East Pacific. Climate change has resulted in warm “Western V” ocean water that wraps around this cool region, amplifying its drought-inducing efficacy. This makes naturally occurring La Niñas more intense and hazardous. To explore the impact of human-induced warming, a formal attribution study is presented and described. In 2017, March–May Western V sea surface temperatures were the warmest on record, and climate change certainly contributed to the severely dry conditions over East Africa, helping place more than 13 million people in peril.
Beginning in northwestern Kenya with the story of Eregae and Aita Nakali, this chapter introduces the new science of climate extremes and extreme event attribution. Between 2015 and 2019, the “fingerprints” of climate change slapped hundreds of millions of people. Extreme heat waves, floods, droughts, and wildfires exacted a terrible toll on developed and developing nations alike. These catastrophes affected hundreds of millions of people and resulted in hundreds of billions of dollars in losses. Fire-afflicted movie stars in California and ranchers in Australia; drought-stricken South Africans; poor flooded fisher-folk in Bangladesh; Houston's middle-class families riven by flood: these are just some of the people who felt the crushing blow of more extreme climate. While humans have always faced the perils of natural disasters, the data suggest that the human and economic cost of climate and weather extremes is increasing rapidly as our population and economies expand and our planet warms rapidly. Since the early 1980s, the number of large catastrophes has quadrupled, inflicting billions of dollars in losses and impacting vulnerable populations on every continent. Understanding the link between extremes and warming is both a moral and an existential imperative.
The amount of energy in the upper ocean is increasing very rapidly. Between 2014 and 2019, the global heat energy increase was equivalent to the energy released by about 12 million one-megaton nuclear bombs. But global warming does not produce an even warming of the world’s oceans. Rather, extra energy builds up and moves around in complex ways. Understanding this fact can save lives. In the near term, this recognition can lead to successful forecasts. In the longer term, this recognition will help us reduce our emissions because we can recognize now how climate change is contributing to extreme weather and catastrophes. For example, in October and November 2019, the western Indian Ocean reached the highest levels of warmth ever observed, while the eastern Indian Ocean was anomalously cold. This combination contributed to extreme flooding and locust outbreaks in East Africa and exceptionally warm and dry conditions over southern Africa and Australia. An accurate conceptual model of climate change can create opportunities for prediction. Adopting an incorrect conception of climate change as the average of collections of climate simulations can cause us to miss these opportunities.
This article investigates the short- and long-term costs of an extreme weather event on retail food prices and consumer expenditures. We utilize the 2011 severe peanut drought as a quasi-natural experiment and find that retail peanut butter prices increased 21.3% as a result of the drought-driven shock in farm peanut production and prices. Moreover, we identify long-term costs due to positive asymmetric price transmission as retail peanut butter prices returned to pre-shock levels much more slowly and remained on average 6.2% higher for 4 years after farm peanut prices returned to pre-shock levels. For consumers, the drought increased peanut butter costs, and the persistence of higher prices in peanut butter led to long-term consumer costs. Peanut butter expenditure on average increased by 4.8% post-shock, with lower-income households increasing expenditures even more. A simple calculation estimates that higher peanut butter prices inflicted a cost of $1.08 billion during the shock, and sticky post-shock peanut butter prices imposed a cost of $628 million to U.S. consumers.
Drought tolerance is a highly complex trait and one of the important components of yield stability in wheat. An experiment was therefore conducted to study the drought tolerance status of 14 high-yielding wheat varieties based on morphological characteristics under a randomized complete block design following factorial arrangement with three replications. Variety × Treatment × Year interactions of wheat genotypes were studied for various morphological traits under normal and drought stress conditions for 2 years in plants grown in pots. Significant differences were observed among the 14 varieties of wheat. Sutlej-86 was found to be highly affected by drought, with maximum reductions in plant height, spike length and number of spikelets/spike. The variety with the maximum tolerance to drought was Bahawalpur-97; this variety also had the lowest reductions in the number of fertile tillers/plant, the number of spikelets/spike, spike weight, the number of grains/spike, 1000-grain weight, grain yield/spike, total biomass and stress susceptibility and tolerance indices. Stronger correlations among the studied attributes under drought stress over normal conditions further highlighted drought stress adversities. The studied traits are thus recognized as drought tolerance indicators for varietal selection, and varieties showing less reduction under drought could be used as a standard check in breeding programmes to identify lineages with drought tolerance and could be recommended for drought-stressed areas.
This study evaluated the yield and water productiivty response of quinoa to regulated deficit irrigation (RDI), partial root-zone drying (PRD) and conventional deficit irrigation (DI) and full irrigation (FI) using surface (SD) and subsurface drip (SSD) systems in 2016 and 2017 in the eastern Mediterranean region of Turkey. The treatments consisted of RDI, PRD50, DI50, DI75 and FI. A rainfed treatment (RF) was also included in the study. The experimental design was split plots with four replications. DI75 and DI50 received 75 and 50% of FI, respectively. PRD50 received 50% of FI, but from alternative laterals. RDI received 50% of FI during vegetative stage until flowering, and then received 100% of water requirement. The results showed that quinoa under SD used slightly more water than SSD due to reduced surface evaporation. RDI resulted in water saving of 23 and 21% for SD and SSD, respectively, compared to FI; and RDI produced statistically similar grain yields to FI. DI75 treatment resulted in water savings of 16% for both drip methods in the first year and 10 and 25% for SD and SSD systems, respectively, in the second year. PRD50 produced greater yield than DI50 eventhough they received the same amount of irrigation water. RF and PRD50 treatments resulted in significantly greater water productivity (WP) values than other treatments. There was no significant difference between SD and SSD regarding the grain and dry matter yields and WP values. Thus, RDI and DI75 appear to be good alternatives to FI for sustainable quinoa production in the Mediterranean region.
A field experiment was carried out for over two seasons (autumn and spring) as a split–split plot scheme based on a randomized complete block design with three replications. The main plots included two irrigation levels of the maximum available water depletion (maximum allowable depletion (MAD)) of 55 and 85% as non-stress and drought-stress environments, respectively, and the subplot accommodated two levels of nitrogen (0 and 62.5 kg N/ha, urea fertilizer); also, 20 barley genotypes were assigned to the sub-subplots. The biplot analysis of both sowing seasons showed that grain yield (GY) had a high positive correlation with total biomass (TB), whereas it had a high negative correlation with proline and total soluble carbohydrate as drought-tolerance-determinant characteristics. The genotypes which had the lowest and highest GY ranked significantly (P ≤ 0.01) different with changing the sowing season under each irrigation level, indicating a larger plant interaction and non-stability in response to the season change (about two-fold), as compared to the change in the irrigation conditions. It could also be concluded that barley genotypes might experience a higher decrease in GY and sensitivity to water deficit in the autumn sowing season, as compared to the spring planting season, which was also intensified by nitrogen application. However, the response to nitrogen application depends on the plant genotype.
This paper evaluates the short-term health effects of in utero drought shock using repeated cross-section household data on Malawi. The main finding reveals that the effects of in utero harvest variability caused by rainfall shocks on child growth indices are driven by the deleterious effects of negative rainfall deviations, namely droughts. Negative rainfall deviation during the agricultural season prior to the gestational period of a child leads to a 21.8 per cent average local level reduction in age-standardized height scores, with the counterpart positive rainfall deviation having no apparent effect. The paper also uses harvest and consumption patterns to establish an important link between early-life malnutrition and growth serving as a precursor for the fetal period programming hypothesis in the literature. The direct impact of embryonic period shocks on growth provides supportive evidence on potential interaction between nutritional and environmental pathways.
The complexity of human roles and responsibilities in the health and continuance of Earth and all its life has been explored by Indigenous writers and activists from a wide variety of perspectives. Of particular importance is the profound relationship between humans and water, the fundamental compact on which all others rely. Through an analysis of literary representations of water, this chapter examines Indigenous stories that center relationships and responsibilities, recognizing the interlocking systems on which all life relies. Authors Linda Hogan (Chickasaw), Leslie Marmon Silko (Laguna), and Tommy Pico (Kumeyaay) engage these concerns by connecting characters and their current conflicts of drought and/or environmental degradation to story traditions about the perils of imbalance and the repercussions of human greed. The life of water represented by seasonal rains, drought, and dynamic waterways reminds readers of the vital roles humans and the more-than-human world play in the climate cycles that support environmental wellbeing.
Summer monsoon rainfall is controlled by a number of factors but in general it is expected to intensify as the Earth becomes warmer. Rainfall is expected to be higher in South Asia, with the exception of Northwest India and Pakistan where drying is predicted. The Indian monsoon will be more prone to significant breaks. More cyclones are expected to make landfall in the Arabian Sea, while in East Asia typhoons will affect eastern China more. Rainfall is not expected to change greatly in China, but higher temperatures will result in more frequent drought especially in North China and the Tibetan Plateau where warming is strongest. Pollution will reduce rainfall, counteracting the effect of higher temperatures. Traditional small-scale farming is more effective at retaining soil moisture and may be more appropriate than large industrial agriculture in coping with the anticipated environmental changes. Sea-level rise is expected to rise approximately 36 cm by 2100, even assuming that CO2 emissions are capped. These rises are expected to more than double the occurrence of major tidal flooding, placing millions of people in jeopardy by the end of the century, especially in Bangladesh and Vietnam.
Mormon Lake, elevation 2166 m with maximum historic surface area of 31.4 km2, lies in a forested endorheic basin covering 103 km2. It is the largest unaltered freshwater body on the 337,000 km2 Colorado Plateau. Prehistorical (before AD 1878) highstands were ca. 9 and 24 m relative to depocenter datum. These levels likely occurred during four multidecadal episodes of cool, wet conditions between ca. 3.55 and 0.20 ka BP. Maximum historical levels (early 1900s) were up to 7.9 m, whereas modern (post-1941) levels were frequently zero or relatively low. Historical climate records indicate reconstructed lake levels correlate directly with annual precipitation and inversely with temperature. Early highstands were associated with above average precipitation and the lowest temperatures of the 116 yr record. The lake receded after 1941; thereafter, frequent drying and low-water levels resulted from recurrent drought and steadily increasing temperatures. Consequently, a wet episode from the 1970s to the 1990s had precipitation like the early 1900s, but highstands were only ca. 3.8 m. The historical lake-level chronology is consistent with changes of hydrologic balance predicted by climate models, that is, reduced effective precipitation (precipitation minus evaporation). These changes, particularly aridification, apparently began in the 1970s or earlier. Global oceanic and atmospheric climate modulate lake levels and regional hydroclimate.
Surface albedo typically dominates the mass balance of mountain glaciers, though long-term trends and patterns of glacier albedo are seldom explored. We calculated broadband shortwave albedo for glaciers in the central Chilean Andes (33–34°S) using end-of-summer Landsat scenes between 1986 and 2020. We found a high inter-annual variability of glacier-wide albedo that is largely a function of the glacier fractional snow-covered area and the total precipitation of the preceding hydrological year (up to 69% of the inter-annual variance explained). Under the 2010–2020 ‘Mega Drought’ period, the mean albedo, regionally averaged ranging from ~0.25–0.5, decreased by −0.05 on average relative to 1986–2009, with the greatest reduction occurring 3500–5000 m a.s.l. In 2020, differences relative to 1986–2009 were −0.14 on average as a result of near-complete absence of late summer snow cover and the driest hydrological year since the Landsat observation period began (~90% reduction of annual precipitation relative to the 1986–2009 period). We found statistically significant, negative trends in glacier ice albedo of up to −0.03 per decade, a trend that would have serious implications for the future water security of the region, because glacier ice melt acts to buffer streamflow shortages under severe drought conditions.