Water Scarcity

Hoover DamWater scarcity is an enormous challenge in many parts of the world, with many of the world’s most important aquifers being drained much faster than they can be replenished. These trends in water availability will have effects on food production systems, water-borne illness patterns, and other water-related diseases.  For example, the aquifer under the North China Plain, where half of China's wheat is grown, is falling at up to three meters/year, and it is estimated that each year 300 million Indians and Chinese are being fed on fossil water that is not being replenished.  Demographic changes are driving sharp increases in global water demand at a time when climate change promises to increase water scarcity in a variety of ways, including more extreme forms of precipitation, dry areas becoming drier, earlier spring runoff from winter snow pack, loss of glacial contributions to dry-season flow, sea level rise and inundation of coastal aquifers with salt water, and hotter temperatures leading to increased evapotranspiration. 

These complex changes in quantity, quality, and timing of water availability, overlaid on significant existing water scarcity and increasing demand, are likely to impact food production, water-borne disease exposure, and water-related diseases.  Changes in land use (e.g., deforestation) also impact water quality and quantity and exposure to water-borne disease in ways that are inadequately understood.  Research to better characterize these challenges and identify approaches to reducing vulnerability is urgently needed.

Learning Objectives

  • L1: Relate and analyze the linkages between drivers of water scarcity and health implications.
  • L2: Describe how water availability and quality affect economic opportunities and human well-being, and how human activity affects water resources.
  • L3: Understand the natural systems and physical properties of water that contribute to its fundamental role in driving Earth systems.
  • L4: Explore how availability of and demand for water resources is expected to change over the next 50 years and what this means for health.

 

  •  
  • 1 of 2
  • »
Wurtsbaugh WA, Miller C, Null SE, DeRose RJ, Wilcock P, Hahnenberger M, Howe F, Moore J. Decline of the world's saline lakes . Nature Geoscience [Internet]. 2017. Publisher's VersionAbstract

Many of the world's saline lakes are shrinking at alarming rates, reducing waterbird habitat and economic benefits while threatening human health. Saline lakes are long-term basin-wide integrators of climatic conditions that shrink and grow with natural climatic variation. In contrast, water withdrawals for human use exert a sustained reduction in lake inflows and levels. Quantifying the relative contributions of natural variability and human impacts to lake inflows is needed to preserve these lakes. With a credible water balance, causes of lake decline from water diversions or climate variability can be identified and the inflow needed to maintain lake health can be defined. Without a water balance, natural variability can be an excuse for inaction. Here we describe the decline of several of the world's large saline lakes and use a water balance for Great Salt Lake (USA) to demonstrate that consumptive water use rather than long-term climate change has greatly reduced its size. The inflow needed to maintain bird habitat, support lake-related industries and prevent dust storms that threaten human health and agriculture can be identified and provides the information to evaluate the difficult tradeoffs between direct benefits of consumptive water use and ecosystem services provided by saline lakes.

 
 
Jaeger WK, Amos A, Bigelow DP, Chang H, Conklin DR, Haggerty R, Langpap C, Moore K, Mote PW, Nolin AW, et al. Finding water scarcity amid abundance using human–natural system models . Proceedings of the National Academy of Sciences [Internet]. 2017;114 (45). Publisher's VersionAbstract

Water scarcity afflicts societies worldwide. Anticipating water shortages is vital because of water’s indispensable role in social-ecological systems. But the challenge is daunting due to heterogeneity, feedbacks, and water’s spatial-temporal sequencing throughout such systems. Regional system models with sufficient detail can help address this challenge. In our study, a detailed coupled human–natural system model of one such region identifies how climate change and socioeconomic growth will alter the availability and use of water in coming decades. Results demonstrate how water scarcity varies greatly across small distances and brief time periods, even in basins where water may be relatively abundant overall. Some of these results were unexpected and may appear counterintuitive to some observers. Key determinants of water scarcity are found to be the cost of transporting and storing water, society’s institutions that circumscribe human choices, and the opportunity cost of water when alternative uses compete.

 
Myers SS. Planetary health: protecting human health on a rapidly changing planet . The Lancet [Internet]. 2017. Publisher's VersionAbstract

The impact of human activities on our planet's natural systems has been intensifying rapidly in the past several decades, leading to disruption and transformation of most natural systems. These disruptions in the atmosphere, oceans, and across the terrestrial land surface are not only driving species to extinction, they pose serious threats to human health and wellbeing. Characterising and addressing these threats requires a paradigm shift. In a lecture delivered to the Academy of Medical Sciences on Nov 13, 2017, I describe the scale of human impacts on natural systems and the extensive associated health effects across nearly every dimension of human health. I highlight several overarching themes that emerge from planetary health and suggest advances in the way we train, reward, promote, and fund the generation of health scientists who will be tasked with breaking out of their disciplinary silos to address this urgent constellation of health threats. I propose that protecting the health of future generations requires taking better care of Earth's natural systems.

Azage M, Kumie A, Worku A, Bagtzoglou AC, Anagnostou E. Effect of climatic variability on childhood diarrhea and its high risk periods in northwestern parts of Ethiopia . PLoS ONE [Internet]. 2017. Publisher's VersionAbstract

Background

Increasing climate variability as a result of climate change will be one of the public health challenges to control infectious diseases in the future, particularly in sub-Saharan Africa including Ethiopia.

Objective

To investigate the effect of climate variability on childhood diarrhea (CDD) and identify high risk periods of diarrheal diseases.

Methods

The study was conducted in all districts located in three Zones (Awi, West and East Gojjam) of Amhara Region in northwestern parts of Ethiopia. Monthly CDD cases for 24 months (from July 2013 to June 2015) reported to each district health office from the routine surveillance system were used for the study. Temperature, rainfall and humidity data for each district were extracted from satellite precipitation estimates and global atmospheric reanalysis. The space-time permutation scan statistic was used to identify high risk periods of CDD. A negative binomial regression was used to investigate the relationship between cases of CDD and climate variables. Statistical analyses were conducted using SaTScan program and StataSE v. 12.

Results

The monthly average incidence rate of CDD was 11.4 per 1000 (95%CI 10.8–12.0) with significant variation between males [12.5 per 1000 (95%CI 11.9 to 13.2)] and females [10.2 per 1000 (95%CI 9.6 to 10.8)]. The space-time permutation scan statistic identified the most likely high risk period of CDD between March and June 2014 located in Huletej Enese district of East Gojjam Zone. Monthly average temperature and monthly average rainfall were positively associated with the rate of CDD, whereas the relative humidity was negatively associated with the rate of CDD.

Conclusions

This study found that the most likely high risk period is in the beginning of the dry season. Climatic factors have an association with the occurrence of CDD. Therefore, CDD prevention and control strategy should consider local weather variations to improve programs on CDD.

Davis KF, Rulli MC, Seveso A, D’Odorico P. Increased food production and reduced water use through optimized crop distribution . Nature Geoscience [Internet]. 2017. Publisher's VersionAbstract

Growing demand for agricultural commodities for food, fuel and other uses is expected to be met through an intensification of production on lands that are currently under cultivation. Intensification typically entails investments in modern technology — such as irrigation or fertilizers — and increases in cropping frequency in regions suitable for multiple growing seasons. Here we combine a process-based crop water model with maps of spatially interpolated yields for 14 major food crops to identify potential differences in food production and water use between current and optimized crop distributions. We find that the current distribution of crops around the world neither attains maximum production nor minimum water use. We identify possible alternative configurations of the agricultural landscape that, by reshaping the global distribution of crops within current rainfed and irrigated croplands based on total water consumption, would feed an additional 825 million people while reducing the consumptive use of rainwater and irrigation water by 14% and 12%, respectively. Such an optimization process does not entail a loss of crop diversity, cropland expansion or impacts on nutrient and feed availability. It also does not necessarily invoke massive investments in modern technology that in many regions would require a switch from smallholder farming to large-scale commercial agriculture with important impacts on rural livelihoods.

  •  
Kurth AE. Planetary Health and the Role of Nursing: A Call to Action . Journal of Nursing Scholarship. 2017.Abstract
Purpose
To discuss the drivers of planetary health, responses, and the role of nursing in making health systems more resilient in an era of increasing stresses. As health providers, scientists, educators, and leaders, nurses have an obligation to prepare for climate change and other impacts of ecosystem strain on human health.
 
Design and Methods
Review of literature relevant to a planetary health framework.
 
Findings
Population displacement, new disease patterns and health needs, stresses on air quality, food production and water systems, and equity concerns, as well as the generation of sustainable energy, are all intimately related to health.
 
Conclusions
Nurses are key to achieving the sustainable development goals that, like the planetary health framework, focus on environmental sustainability and human well-being. Nurses contribute to resilient health systems, as trusted leaders and providers of health care, and as advocates and change makers impacting the world.
 
Clinical Relevance
It is critical that nurses and other health professionals consider the multiple effects of ecosystem strain on human health, and anticipate population health and health system planning and response.
  •  
  • 1 of 11
  • »

Licensing & Fair Use Agreement

All of the content in the collection is licensed for sharing and modification under a Creative Commons license (CC BY 4.0). If you are involved in education on planetary health topics and would like to share teaching materials, please enrich our community! By sharing materials you agree to the terms and conditions outlined in our legal framework. You can share materials here