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Climate, Conflict, and Social Stability: What Does the Evidence Say?
Abstract
Are violent conflict and socio-political stability associated with changes in climatological variables? We examine 50 rigorous quantitative studies on this question and find consistent support for a causal association between climatological changes and various conflict outcomes, at spatial scales ranging from individual buildings to the entire globe and at temporal scales ranging from an anomalous hour to an anomalous millennium. Multiple mechanisms that could explain this association have been proposed and are sometimes supported by findings, but the literature is currently unable to decisively exclude any proposed pathway. Several mechanisms likely contribute to the outcomes that we observe.
... Different perspectives strived to link security with the environment by narrowing down the debate to violent conflicts caused by varied environmental issues. Hsiang and Burke (2014) compiled studies that claimed a causal association between climate and social instability, and found "strong linkages" between climatic extremes (such as high temperatures or periods of drought) and decrease in social stability, even if an exact link and reasoning is unclear. ...
The following dissertation discusses the process of securitization of water scarcity in Jordan which took place in years 2013-2020. Jordanian authorities utilised a security narrative framing the Syrian refugee influx as aggravating water scarcity in the country. During the course of the analysis, special attention was paid to audiences the securitizing move was targeted towards, investigating their identity, influence and relations with other actors involved. The study was guided by a sociological approach to securitization that goes beyond Copenhagen School's initial formulation. It was conceptualised as a non-linear social process and a discursive practice with mutually constitutive agents, structures, and contexts. Theoretical base was supplemented with primary sources-Jordanian official documents and news articles-which revealed that the narrative adhered to the global water security discourse and relied on established heuristic cues to invoke security in relation to the refugees-water scarcity-Jordan nexus. This dissertation argues that the securitizing move was targeting both domestic and international audiences, with the latter, consisting of donor community, being the enabling audience and having a significant influence on threat construction. The findings further reaffirmed the important role of international donors in Jordan.
... The most vulnerable countries and regions to ACC, namely those that have extensive arid lands with water scarcity problems, countries with economies that are highly dependent on agriculture and with low socioeconomic development, fragile states, small island states, and the Arctic polar region, are also areas of significant military engagement [87]. However, the causal relation between climate change and conflict is difficult to establish [88,89]. During the Holocene, there is evidence that the consequences of natural climate change in conjunction with other stresses have led to armed conflicts and the disintegration of societies, and in some cases contributed to societal collapse [90][91][92][93]. ...
... The most vulnerable countries and regions to ACC, namely those that 341 have extensive arid lands with water scarcity problems, countries with economies that are 342 highly dependent on agriculture and with low socioeconomic development, fragile states, 343 small island states, and the Arctic polar region, are also areas of significant military en-344 gagement [88]. However, the causal relation between climate change and conflict is diffi-345 cult to establish [89,90]. More recently, there is evidence that the consequences of natural 346 climate change in conjunction with other stresses have led to armed conflicts and the dis-347 integration of societies, and in some cases contributed to societal collapse [91][92][93][94]. ...
Global greenhouse gas (GHG) emissions have continued to grow persistently since 1750. The United Nations Framework Convention on Climate Change (UNFCCC) entered into force in 1994 to stabilize GHG emissions. Since then, the increasingly harmful impacts of global climate change and repeated scientific warnings about future risks have not been enough to change the emissions trend and enforce policy actions. This paper synthesizes the climate change challenges and the insofar insufficient mitigation responses via an integrated literature review. The fossil industry, mainstream economic thinking, national rather than international interests, and political strive for short-term interests present key barriers to climate mitigation. A continuation of such trends is reflected in the Dice model, leading to a 3.5 °C temperature increase by 2100. Despite receiving the Nobel Prize for integrating climate change into long-run macroeconomic analysis via the Dice model, increases in global mean temperatures overshooting the 1.5 °C to 2 °C Paris targets imply an intensified disruption in the human–climate system. Past and present policy delays and climate disruption pave the way for solar radiation management (SRM) geoengineering solutions with largely unknown and potentially dangerous side effects. This paper argues against SRM geoengineering and evaluates critical mitigation solutions leading to a decrease in global temperatures without overshooting the Paris targets. The essential drivers and barriers are discussed through a unified approach to tipping points in the human–climate system. The scientific literature presents many economically and technologically viable solutions and the policy and measures required to implement them. The present paper identifies the main barriers to integrating them in a globally cooperative way, presenting an efficient, long-term, and ethical policy approach to climate change.
... Compared to this 5-year moving average, the 11-year moving average showed a 98% increase in PPR, and the 25-year moving average a 134% increase. This evidence is consistent with the argument that conflict between Murcia and church leaders was more likely under conditions of environmental duress caused by drought (Miguel et al. 2004, Hsiang andBurke 2014). ...
We analyze the case of pro-pluvia rogations (PPR) performed by the Catholic Church in Murcia, Spain since 1600. PPR were ceremonies to ask God for rain. We show a structural break in the prayer data during the 1830s, coinciding with the end of the ancien régime in Spain. PPR responded to environmental shocks and were used by the civil and ecclesiastical authorities to control the population, ensure stability, and maintain the status quo. Thus, PPR in Murcia have acted as a social resilience instrument. At the same time, PPR highlight the conflict between civil and religious authorities and within religious authorities. Understanding the motives, timing, and other characteristics of religious rituals is crucial to understand the evolution of institutions, the persistence of beliefs and strategies for social adaptation to the environment over the long run.
... Going beyond prediction and assessment, Indigenous knowledge and practice can also be leveraged to develop climate adaptation approaches. Studies evaluating the perception and knowledge of informants about climate change also reveal vernacular responses, including Codjoe et al. (2014), Hsiang and Burke (2014), Tahmasebi (2012), Leiserowitz et al. (2010), and Hartman and Sugulle (2009). These studies provide evidence that climate change and drought have disproportionate economic and social impacts on peoples who are strongly dependent on natural resources, especially nomadic pastoralists. ...
Nomadic pastoral communities are considered one of the most vulnerable to climate change. While indigenous knowledge can play an effective role in mitigating or responding to some impacts of climate change, the extent of their capacity to adapt their livestock and rangeland management is under question. This research aims to assess the scope and applicability of climate change related knowledge acquired in the management of summer rangeland, with a case study in Semirom, Isfahan Province, Iran. To do so, objective weather conditions (precipitation, min- and maximum temperatures) were evaluated using the Mann-Kendall non-parametric test, and compared with subjective evaluations by nomad community members. Specifically, the study targeted a community of 7,700 members of the Qashqai, a conglomeration of nomadic tribes in Iran. Their understanding of the weather was evaluated using focus groups and self-administered questionnaires, with a descriptive approach to data analysis.
The findings of the climatic investigation revealed a possible shift in the climate in the study area, particularly in winter and autumn. The findings of subjective evaluation showed similar changes in wind, precipitation, and temperature to be the main characteristics of climate change in the region, with about 90 percent of informants directly citing decreasing precipitation and increasing temperature and wind speeds. The community evaluation also highlighted some adaptations to climate change, such as delays in beginning the seasonal migration, increased reliance on concrete homes, reservoir construction, decreasing livestock yields, and increasing diversification of resources to feed livestock. Understanding the perceptions of nomadic pastoralists, their meteorological basis, and ongoing climate adaptations can facilitate governmental planning.
... Climate change is reflected by the long-term statistical shifts of weather, including the change of average weather conditions and the change of distribution of weather conditions around the average, such as extreme weather events (Wu et al., 2016). Climate change is an increasing challenge to the sustainable development of human society, by imposing substantial threats to ecological stability (Thuiller et al., 2005), food security (Wheeler and Braun, 2013), and energy supply (Turton and Barreto, 2006), impeding economic development (Tol, 2009;Rogerson, 2016), and increasing social instability (Hsiang and Burke, 2014). The University College London (UCL)-Lancet Commission issued a warning in 2009, which called climate change "the biggest global health threat of the 21st century" (Costello et al., 2009). ...
High temperature is a growing threat and impacts public health through different exposure mechanisms. Our study constructs a comprehensive exposure measurement based on temperature variability, duration, and effective influence range. We investigate human responses to high temperatures through self-rated health scores based on individual-level data from China Labor-force Dynamic Survey (CLDS). Results show that higher temperature and temperature variability significantly decrease self-rated health scores. Subjective health risk is most significantly related to the cumulative temperature in the previous two weeks. We also find that the exposure effects at night and on weekdays are more severe. Workers who experience greater exposure from commuting and work environments are negatively impacted by high temperatures. In addition, men, the elderly, middle and low education groups, rural residents are more likely to be impacted by high temperatures.
Despite colossal economic and human losses caused by conflict and violence, designing effective policies to avoid conflict remains challenging. While the literature has proposed a voluminous set of candidate predictors, their robustness is questionable and model uncertainty masks the true drivers of conflicts and wars. Considering a comprehensive set of 34 potential determinants in 175 post-Cold-War countries, we employ stochastic search variable selection (SSVS) to sort through all 2³⁴ possible models to address model uncertainty. We find past conflict constitutes the most powerful predictor of current conflict: Path dependency matters. Also, larger shares of Jewish, Muslim, or Christian citizens are associated with increased conflict, while economic and political factors remain less relevant than colonial origin and religion. Our results help future researchers and policymakers by inching towards causality and providing a standard set of covariates that need to be accounted for in designing any relevant policies.
During its Classic period (250-950 A.D.), Maya civilization reached a zenith. At its peak, around 750 A.D., the population may have topped 13 million. Then, between about 750 and 950 A.D., their society imploded. The Maya abandoned what had been densely populated urban centers, leaving their impressive stone edifices to fall into ruin. The demise of Maya civilization (which archaeologists call "the terminal Classic collapse") has been one of the great anthropological mysteries of modern times. What could have happened? Scholars have advanced a variety of theories over the years, pinning the fault on everything from internal warfare to foreign intrusion, from widespread outbreaks of disease to a dangerous dependence on monocropping, from environmental degradation to climate change. Some combination of these and other factors may well be where the truth lies. However, in recent years, evidence has mounted that unusual shifts in atmospheric patterns took place near the end of the Classic Maya period, lending credence to the notion that climate, and specifically drought, indeed played a hand in the decline of this ancient civilization.
Roughly a billion people around the world continue to live in state of chronic hunger and food insecurity. Unfortunately, efforts to improve their livelihoods must now unfold in the context of a rapidly changing climate, in which warming temperatures and changing rainfall regimes could threaten the basic productivity of the agricultural systems on which most of the world’s poor directly depend. But whether climate change represents a minor impediment or an existential threat to development is an area of substantial controversy, with different conclusions wrought from different methodologies and based on different data.
This book aims to resolve some of the controversy by exploring and comparing the different methodologies and data that scientists use to understand climate’s effects on food security. In explains the nature of the climate threat, the ways in which crops and farmers might respond, and the potential role for public and private investment to help agriculture adapt to a warmer world. This broader understanding should prove useful to both scientists charged with quantifying climate threats, and policy-makers responsible for crucial decisions about how to respond. The book is especially suitable as a companion to an interdisciplinary undergraduate or graduate level class.
"This book provides a much needed analysis of the interactions between climate change and the food system, with emphasis on how food security is likely to be affected and interventions needed to adapt to a warmer world."
Per Pinstrup-Andersen, Cornell University, New York, USA
A rapidly growing body of research examines whether human conflict can be affected by climatic changes. Drawing from archaeology, criminology, economics, geography, history, political science, and psychology, we assemble and analyze the 60 most rigorous quantitative studies and document, for the first time, a striking convergence of results. We find strong causal evidence linking climatic events to human conflict across a range of spatial and temporal scales and across all major regions of the world. The magnitude of climate’s influence is substantial: for each one standard deviation (1σ) change in climate toward warmer temperatures or more extreme rainfall, median estimates indicate that the frequency of interpersonal violence rises 4% and the frequency of intergroup conflict rises 14%. Because locations throughout the inhabited world are expected to warm 2σ to 4σ by 2050, amplified rates of human conflict could represent a large and critical impact of anthropogenic climate change.
We explore the relationship between drought and civil war. We show that the link between rainfall, temperature and civil war found in the literature may be driven by aggregate shocks (such as global climate) that were not accounted for. A standard differences-in-differences specification relying only on within country variation reveals a much weaker and insignificant link between weather variables and civil war. To increase statistical power, we propose a country-specific measure of drought that describes social exposure to water stress in a more efficient way than rainfall and temperature. We use the Palmer Drought Severity Index (PDSI) which combines rainfall, temperature (and soil texture) and takes important aspects that were missing from previous studies into account: nonlinearities - the effect of contemporaneous rainfall and temperatures depends on the climate history -, interaction effects - e.g. low rainfall is more important in hot years -, and threshold effects due to the limited capacity of the soil - e.g. rainfall water will run off when the soil layers are full. We continue to find a weak positive link between drought and civil war.
While the persistence of criminal activity is well documented, this may be due to persistence in the unobserved determinants of crime. There are good reasons to believe, however, that there may actually be a negative relationship between crime rates in a particular area due to temporal displacement. We exploit the correlation between weather and crime to examine the short-run dynamics of crime. Using variation in lagged crime rates due to weather shocks, we find that the positive serial correlation is reversed. These findings suggest that the long-run impact of temporary crime-prevention efforts may be smaller than the short-run effects.
Problems involving causal inference have dogged at the heels of Statistics since its earliest days. Correlation does not imply causation and yet causal conclusions drawn from a carefully designed experiment are often valid. What can a statistical model say about causation? This question is addressed by using a particular model for causal inference (Rubin, 1974; Holland and Rubin, 1983) to critique the discussions of other writers on causation and causal inference. These include selected philosophers, medical researchers, statisticians, econometricians, and proponents of causal modelling.
Can culture mitigate conflicts triggered by economic shocks? In light of the extraordinary emphasis that Confucianism places on subordination and pacifism, we examine its role in possibly attenuating peasant rebellion within the historical context of China (circa 1651–1910). Our analysis finds that, while crop failure triggers peasant rebellion, its effect is significantly smaller in counties characterized by stronger Confucian norms as proxied by Confucian temples and chaste women. This result remains robust after controlling for a long list of covariates and instrumenting Confucian norms using ancient Confucian sages (500 B.C.-A.D. 550) to address concerns of measurement error and reverse causality.
Problems involving causal inference have dogged at the heels of statistics since its earliest days. Correlation does not imply causation, and yet causal conclusions drawn from a carefully designed experiment are often valid. What can a statistical model say about causation? This question is addressed by using a particular model for causal inference (Holland and Rubin 1983; Rubin 1974) to critique the discussions of other writers on causation and causal inference. These include selected philosophers, medical researchers, statisticians, econometricians, and proponents of causal modeling.
Using centuries of Nile flood data, I document that during deviant Nile floods, Egypt's highest-ranking religious authority was less likely to be replaced and relative allocations to religious structures increased. These findings are consistent with historical evidence that Nile shocks increased this authority's political influence by raising the probability he could coordinate a revolt. I find that the available data provide support for this interpretation and weigh against some of the most plausible alternatives. For example, I show that while Nile shocks increased historical references to social unrest, deviant floods did not increase a proxy for popular religiosity. Together, the results suggest an increase in the political power of religious leaders during periods of economic downturn.