The global population is expected to increase from 7 billion to over 9.1 billion by the year 2050 (Godfray et al., 2010). To ensure the food security, approximately 70% more food than the available at present will be needed, which is expected to put agricultural production systems and the environment under pressure (FAO, 2013). According to Intergovernmental Panel on Climate Change (IPCC) projected climate change scenarios, the concern of increasing temperature and rainfall variability with drought events is more likely to further widen the gap between food supply and demand. Assessing and improving the resilience of cropping systems to climate change is a very critical issue, especially in the Mediterranean region (Rivington et al. 2007). Normally, in addition to being considered as a measure of stability and persistence (Gunderson and Holling 2002; Reggiani et al. 2002), some refer to resilience as the capacity of an ecosystem to shield itself against extreme factors (Carpenter et al. 2001). The ability of cropping systems to resist disturbance defines how resilience a system is (Enfors and Gordon 2007). Assessing spatial and temporal adaptations of a specific land use option or farming system, allows to identify the strategies/combination of strategies, priorities and measures which support the resilience of a cropping system against a change/set of changes. Diversities within land cover (e.g. cereals, legumes, orchards...etc.), farming system (i.e. rain-fed, irrigated and supplementary irrigated), cultivation system (e.g. intercropped farm, monoculture farm, mixed farm...etc.), soil type and fertility (Rodriguez et al. 2011) and availability of water (Tavakkoli and Oweis, 2004; Ilbeyi et al. 2006), define the resilience of cropping systems and their capability to adapt to climate change (Reidsma et al. 2010), in the Mediterranean region. The Beqaa plain of Lebanon is a typical semi-arid/dry Mediterranean area. It is around 1000m above sea level (a.s.l.). As agriculture is the main economic activity, wheat and potato are the two major cultivated crops. The average annual precipitation is around 600mm (Darwish et al., 2008), with a useful rainfall below wheat-water requirements. For this reason, the introduction of partial supplemental irrigation, i.e., applying limited amount of water in spring to attenuate drought spells during the rainy season, is one of the followed measures to increase wheat productivity. Similar studies, nevertheless, indicated that grain yield would be significantly increased (up to more than 3 times) by full supplemental irrigation (Tavakkoli and Oweis, 2004). Crop simulation models (e.g. CropSyst) are effectively applied for gap filling and extrapolating the results, especially when coped with GIS interface. These models can be used to foresee and assess the impacts of weather, farm properties, seed varieties, plant characteristics and agricultural practices on the environment. In the same context, Van Keulen and Seligman (1987) indicated that such models could be used over a period of time, which is long enough, to assess the effect of different factors on the crop performance by characterizing the climatic variability of a specific site. Thus, as we face the threat to sustain our food production systems, more attention shall be invested in sustaining high productivity systems, with more socio-economic returns and less environmental impacts.