The Global Food System and Water Crisis: 10 Science Papers from the Past Year

[This is the second in a four-part series of guest posts by first year students in Columbia's Sustainable Development program]

The Global Food System and Water Crisis: 10 Science Papers from the Past Year

By StephanieLackner, Xiaojie Zhang, Kayleigh Campbell

To get caught up on the latest research on the global food system and water crisis we did a survey of the must-read articles from the last twelve months.  The requirements to make our list were simple.  First, the article had to be from the Research Articles or Reports sections of Science or the Review, Articles, or Letters sections of Nature published between May 2011 and April 2012.  Then we picked the ones that we thought would have the most significant impact on humans, were the most immediate or critical concerns, or were the most unique solutions to the current crises faced.  And here they are…

How much groundwater does Africa have?

Quantitative maps of groundwater resources in Africa

A M MacDonald, H C Bonsor, B É Ó Dochartaigh and R G Taylor

Abstract: In Africa, groundwater is the major source of drinking water and its use for irrigation is forecast to increase substantially to combat growing food insecurity. Despite this, there is little quantitative information on groundwater resources in Africa, and groundwater storage is consequently omitted from assessments of freshwater availability. Here we present the first quantitative continent-wide maps of aquifer storage and potential borehole yields in Africa based on an extensive review of available maps, publications and data. We estimate total groundwater storage in Africa to be 0.66 million km3 (0.36–1.75 million km3). Not all of this groundwater storage is available for abstraction, but the estimated volume is more than 100 times estimates of annual renewable freshwater resources on Africa. Groundwater resources are unevenly distributed: the largest groundwater volumes are found in the large sedimentary aquifers in the North African countries Libya, Algeria, Egypt and Sudan. Nevertheless, for many African countries appropriately sited and constructed boreholes can support handpump abstraction (yields of 0.1–0.3 l s−1), and contain sufficient storage to sustain abstraction through inter-annual variations in recharge. The maps show further that the potential for higher yielding boreholes ( > 5 l s−1) is much more limited. Therefore, strategies for increasing irrigation or supplying water to rapidly urbanizing cities that are predicated on the widespread drilling of high yielding boreholes are likely to be unsuccessful. As groundwater is the largest and most widely distributed store of freshwater in Africa, the quantitative maps are intended to lead to more realistic assessments of water security and water stress, and to promote a more quantitative approach to mapping of groundwater resources at national and regional level.

Click to enlarge. Copyright ERL

See related field experiment on valuing ground water protection here.

h/t Kyle

Interfacing Water, Climate, And Society: A Resource List

The Research Applications Laboratory at NCAR has a nice wiki-like resource list for folks interested in the interface between water, climate and society. The list isn't comprehensive, but its useful and has sections on:

• Undergraduate Level Degree Programs
• Graduate Level Degree Programs
• Post-graduate Opportunities
• Academic Research Groups
• Professional Development and Research Training
• Professional Networks
• Boundary Organizaions
• Journals
• References
• Funding Programs
• Conferences

Check it out here.

Valuing clean water in rural Kenya

My big sister spent a year in Malawi working on improving communal water infrastructure.  She came home fed up because, among other things, it seemed like nobody was willing to pay for investments in their own infrastructure (if I recall correctly, the Clinton Foundation was trying to pay for the initial construction, but the communities weren't even willing to pay for the maintenance).  I found this puzzling and wasn't sure I believed it at the time, but I guess I do now since the QJE says so.  My big sister has really good intuition.

[This work suggests how public and private infrastructure can be compliments.  Protection of public water sources isn't as effective (or highly valued, probably) when recontamination of water occurs in the home.]

SPRING CLEANING: RURAL WATER IMPACTS, VALUATION, AND PROPERTY RIGHTS INSTITUTIONS
MICHAEL KREMER, JESSICA LEINO, EDWARD MIGUEL, ALIX PETERSON ZWANE

Abstract: Using a randomized evaluation in Kenya, we measure health impacts of spring protection, an investment that improves source water quality. We also estimate households’ valuation of spring protection and simulate the welfare impacts of alternatives to the current system of common property rights in water, which limits incentives for private investment. Spring infrastructure investments reduce fecal contamination by 66%, but household water quality improves less, due to recontamination. Child diarrhea falls by one quarter. Travel-cost based revealed preference estimates of households’ valuations are much smaller than both stated preference valuations and health planners’ valuations, and are consistent with models in which the demand for health is highly income elastic. We estimate that private property norms would generate little additional investment while imposing large static costs due to above-marginal-cost pricing, private property would function better at higher income levels or under water scarcity, and alternative institutions could yield Pareto improvements.