Food shortages are the largest proximate cause of conflict---studies overwhelmingly go negative

A growing number of studies of environmental stressors and social conflict posit that future wars will be fought over diminishing resources (Miguel et al. 2004; Burke et al. 2009;O ’ Loughlin et al. 2012; Scheffran et al. 2012 ). Building on insights from these studies, as well as other suggestive accounts (e.g. Brinkman and Hendrix 2011 ;Hendrix and Brinkman 2013 ; Messer and Cohen 2006 ;Prunier 2008 ), the present study demonstrates empirically, for the first time, the existence of a systemic relationship between conflict on the one hand, and food (in) security on the other, both globally and locally. Specifically, highly disaggregated cropland-based measures of food insecurity are shown to produce a significant effect on the incidence of inter and intra-state armed conflict worldwide. Unlike the majority of previous studies, which rely primarily on country-level indicators (Miguel et al. 2004 ; Burke et al. 2009 ; Scheffran et al. 2012 ;Buhaug 2010 ) or focus specifically on sub-Saharan Africa (Miguel et al. 2004 ; Burke et al. 2009;O ’ Loughlin et al. 2012;Buhaug 2010; Fjelde and Hultman 2014 ), the present approach uses geographic factors to estimate the regional sub-state distribution of conflict globally. Two agricultural output measures, the percent of cropland in a given region and the amount of cropland per capita within agricultural regions, are used to proxy for the demand and supply aspects of food security, respectively (Barrett 2010 ). Using logistic regression (i.e., logit) models, these measures are then paired with a large number of political, economic, and climatic indicators in order to estimate the direct effects of food security on violent conflict. Evidence suggests that conflict occurs in areas with higher access to, but lower availability of, food resources. Together these findings imply that food insecurity produces an independent effect on contemporary social and political conflict. While relatively little research directly addresses the relationship between food insecurity and conflict specifically, numerous studies have implied that such a relationship exists. For instance, in their analysis of the relationship between climate variability and conflict in Sub-Saharan Africa, Burke et al. found that B [t]emperature variables are strongly related to conflict incidence over our historical panel ^ (2009 , 20,670. See also Miguel et al. 2004 ; Koubi et al. 2012 ). They further hypothesize that, B [t]emperature can affect agricultural yields both through increases in crop evapotranspiration (and hence heightened water stress in the absence of irrigation) and through accelerated crop development...reducing African sta- ple crop yields by 10 % – 30 % per °C of warming ^ (ibid. 20,672). Somewhat more cautiously, O ’ Loughlin et al. conclude that, B [o]ur study and other studies question the evidence that climatic variability is uniformly driving up the risk of conflict in sub-Saharan Africa, ^ while also noting that B the positive association between instability and temperature may result from the harmful effects of high temperatures on food products such as maize ^ (2012, 18,347). While these conclusions were supported by subsequent studies (Raleigh and Kniveton 2012; Hendrix and Salehyan 2012 ;Hsiangand Meng 2014 ), other scholars question the validity of these findings and show that the incidence of conflict is primarily related to political and economic conditions (e.g. Buhaug 2010 ). In common with all these studies, however, is the insight that a major mechanism by which climate change increases the likelihood of conflict is through its effects on food supplies.