Given the high dependency on agriculture of hundreds of millions of poor and food-insecure rural people, the potential impacts on agricultural incomes - with economy-wide ramifications in low-income countries that are highly dependent on agriculture - are a major concern. The IPCC also helped catalyse the development of Shared Socio-economic Pathways (SSPs), which describe alternative development futures, to be used alongside the RCPs to analyse feedback between climate change and socioeconomic factors (Box 7). The authors compare the effects of the exogenous climate change shock on yields of four crop aggregates - coarse grains, oil seeds, wheat and rice - which account for about 70 percent of the global crop harvested area.