Solar energy for irrigation: mitigation and adaptation option for the Mediterranean?

Project description: 
The countries of the Mediterranean region cover 8,760 million km2 and hold 430 million people (FAO 2003). These countries represent 7% of the world population, but they account for 25% of world food imports (Mediterra, 2008). Roughly speaking, around 22 % of the population of these countries works in agriculture, cultivating a total of 130 million ha (Nunes Correia 1999) and producing a gross value of 225 billion US$ per year (FAO 2012). The Mediterranean is characterized by natural climate variability, and spatially and temporally variable water scarcity. Currently, 108 million inhabitants, mainly in the Southern Mediterranean, have water availability of less than 1000 m3 yr-1 (Hallegatte 2010) and most Mediterranean areas experience water deficit (Nunes Correia 1999). Agriculture is the main user of this scarce resource: only about 15 % of cultivated area is irrigated but it accounts in 15 out of 19 countries for more than 50 % of the total water withdrawal (FAO 2012; Eulisse et al. 2009; Nunes Correia 1999).

75-95% of the energy supply in the Mediterranean is produced with fossil fuels. This situation makes the Mediterranean vulnerable to future oil price shocks and reveal a high dependence on fossil fuel reserves and on the future geopolitical strategies of the oil exporters (Hallegatte 2010). But more importantly, it leaves the door open for a positive feedback: climate change may lead to higher irrigation water requirements, which in turn would need more energy and would lead, at the end, to more fossil fuel burning and more climate change. This project aims to evaluate the possibility of breaking this positive feedback by testing the potentials of solar energy to drive future irrigation. The project is structured in the following research questions:

1. Does climate change increase irrigation water requirements in the Mediterranean area? 2. How much energy demand increase can be expected due to higher irrigation water requirements? 3. How much money and roof surface would be needed to drive irrigation fully with solar energy? 4. Can a switch of irrigation systems reduce irrigation water requirements and/or energy requirements of irrigation today and in future?

This project makes use of geographical and statistical as well as modelling experiments. In order to account for the interlinkages between land use and the water balance, an ecosystem modelling approach is needed. LPJmL, a process-based, biogeochemical, dynamic global vegetation and hydrology model, is therefore being used and further developed to tackle these questions.

Eulisse, E., Hemmami, M., Koopmanschap, E. (eds.) (2009): Sustainable Use of Water in Agriculture. Indicators and Trends for Water Resources Conservation. In: Proceedings of the 3rd training course “European Sustainable Water Goals” Venice, October 5-9, 2009. 
FAO (2003): CLIMAGRImed. About Mediterranean Region. 
FAO (2012): FAOSTAT. 
Hallegatte, S. (2010): Climate Change and the Mediterranean Region. Meteo France. 
Mediterra (2008): The future of agriculture and food in Mediterranean countries. CIHEAM edition, 355pp. 
Nunes Correia, F. (1999): Water resources in the Mediterranean. Water International 24(1): 22-30.