In the May 22 2010 issue of the Economist, there is an excellent article titled
with the subheading
“Mostly because of farming, water is increasingly scarce. Managing it better could help”
This article effectively presents the vulnerability view that is consistent with what we urged in our paper
Pielke Sr., R., K. Beven, G. Brasseur, J. Calvert, M. Chahine, R. Dickerson, D. Entekhabi, E. Foufoula-Georgiou, H. Gupta, V. Gupta, W. Krajewski, E. Philip Krider, W. K.M. Lau, J. McDonnell, W. Rossow, J. Schaake, J. Smith, S. Sorooshian, and E. Wood, 2009: Climate change: The need to consider human forcings besides greenhouse gases. Eos, Vol. 90, No. 45, 10 November 2009, 413. Copyright (2009) American Geophysical Union
where we wrote
“The impact on water quality and water quantity, for example, is a critically important societal concern. The water cycle is among the most significant components of the climate system and involves, for example, cloud radiation, ice albedo, and land use feedbacks [NRC, 2003]. Regional and local variations in water availability, water quality, and hydrologic extremes (floods and droughts) affect humans most directly.”
We recommend that the next assessment phase of the IPCC (and other such assessments) broaden its perspective to include all of the human climate forcings. It should also adopt a complementary and precautionary resource- based assessment of the vulnerability of critical resources (those affecting water, food, energy, and human and ecosystem health) to environmental variability and change of all types.
“We ….. propose that one should not rely solely on prediction as the primary policy approach to assess the potential impact of future regional and global climate variability and change. Instead, we suggest that integrated assessments within the framework of vulnerability, with an emphasis on risk assessment and disaster prevention, offer a complementary approach [Kabat et al., 2004].”
as well as in posts on my weblog; e.g. see where I wrote
“There are 5 broad areas that we can use to define the need for vulnerability assessments : water, food, energy, health and ecosystem function. Each area has societally critical resources. The vulnerability concept requires the determination of the major threats to these resources from climate, but also from other social and environmental issues. After these threats are identified for each resource, then the relative risk from natural- and human-caused climate change (estimated from the GCM projections, but also the historical, paleo-record and worst case sequences of events) can be compared with other risks in order to adopt the optimal mitigation/adaptation strategy.”
The Economist article includes the perceptive and very important text
“Nature has decreed that the supply of water is fixed. Meanwhile demand rises inexorably as the world’s population increases and enriches itself. Homes, factories and offices are sucking up ever more. But it is the planet’s growing need for food (and the water involved in producing crops and meat) that matters most. Farming accounts for 70% of withdrawals.”
“Although the supply of water cannot be increased, mankind can use what there is better—in four ways. One is through the improvement of storage and delivery, by creating underground reservoirs, replacing leaking pipes, lining earth-bottomed canals, irrigating plants at their roots with just the right amount of water, and so on. A second route focuses on making farming less thirsty—for instance by growing newly bred, perhaps genetically modified, crops that are drought-resistant or higher-yielding. A third way is to invest in technologies to take the salt out of sea water and thus increase supply of the fresh stuff. The fourth is of a different kind: unleash the market on water-users and let the price mechanism bring supply and demand into balance. And once water is properly priced, trade will encourage well-watered countries to make water-intensive goods, and arid ones to make those that are water-light.”
“Even if the world manages to limit depletion, many water-related problems will persist. About 1 billion people are still without access to a decent water supply, while others suffer from flooding, pollution and poor sanitation. Yet if man wants to solve these problems, he can. He has applied far more money and know-how to issues far less important than the shortage of water. And if he does tackle them successfully, the big causes of human suffering—disease and poverty—will be automatically alleviated. Investing more thought and cash in the better use of the world’s most valuable commodity is surely worthwhile.”
The entire article is worth reading!