Adapting raw industrial and domestic water supply to climate change could cost US$ 12 billion per year, with up to 90% of this needed in developing countries, according to new research . A research team from the Netherlands, US and UK found that the highest costs are in Sub-Saharan Africa. Though US$ 12 billion seems a lot, the team stressed that the baseline costs of meeting existing and future demand for water by 2050 in most regions were far greater than adaptation costs.
“Many studies have already shown that the developing world is particularly vulnerable to the impacts of climate change,” Philip Ward of the VU University Amsterdam in the Netherlands told environmentalresearchweb. “In this study we show that the costs of adaptation to climate change in the industrial and municipal water supply sector are also greater for developing countries than for developed countries, both in absolute terms and as a percentage of GDP.”
The highest climate adaptation costs were for sub-Saharan Africa, where western Central Africa is projected to dry, followed by Latin America, which is likely to see increased seasonal and interannual rainfall variability in eastern Brazil.
Before calculating the climate adaptation costs, the researchers analysed the baseline costs needed to meet existing and future demand for water by 2050 without the effects of climate change. These baseline costs also covered the elimination of existing backlogs and the consequences of socioeconomic development.
The researchers then analysed the effect of adaptation to climate change over and above this baseline, using one emissions scenario and two global climate models to project the effects of climate on water supply.
“We found that in most regions the baseline costs far exceed adaptation costs,” said Ward. “This supports the notion of mainstreaming climate-change adaptation, and current and future climate vulnerability, into broader policy aims. It raises the question of ‘how much climate change adaptation should be factored into the current design of water supply systems?’ “
On a global scale, the baseline costs for water supply were $73 billion per year, compared with $12 billion per year for adaptation to climate change.
The researchers fixed the cost of meeting increased demand at US$ 0.30/cubic meter, whether this was met by additional surface reservoirs or other techniques, such as desalination, recycling, or rainwater harvesting. ,
The building of reservoirs is controversial as it can cause heavy environmental and social impacts. The team’s projections indicate that under these assumptions, global reservoir storage capacity would need to increase by around 34–36% by 2050 to cope with water demand.
The researchers hope their work can assist ongoing climate negotiation, such as COP-16, the United Nations Climate Change Conference in Cancun, which ends on 10 December 2010.
 Ward, P.J. … [et al.] (2010). Partial costs of global climate change adaptation for the supply of raw industrial and municipal water: a methodology and application. Environmental research letters ; vol. 5, no. 4 ; 044011. doi: 10.1088/1748-9326/5/4/044011
Source: Liz Kalaughe, environmentalresearchweb, 08 Dec 2010