Research

Overview

Global climate change is projected to generate wide-ranging impacts on ecological and human systems, from coral reef and species loss, to agricultural and human health effects. Communities in the Global South are expected to bear the brunt of the consequences of climate change, while richer nations shoulder far greater responsibility for adding carbon to the atmosphere (IPCC, 2014). In Africa, the context for the studies in my dissertation, communities are expected to face a high risk of reduced water availability and drought, crop failure, and changes to the geographic range and incidence of vector and water borne diseases (Lobell et al., 2011; IPCC, 2014, p 21).

I am a quantitative environmental political scientist who studies human security impacts of climate change and climate stress. How will climate change impact human political and social conditions? How can international actors, governments and local communities respond, to increase resilience and equity and prevent the worst of these outcomes? I employ methods from econometrics and data science; informed by political science, development economics, earth systems science and geography; and generate my findings using data from surveys, behavioral games, administrative records, satellite sources and climate models. My current research focuses in particular on links between climatic conditions and violent conflict. Do higher temperatures or droughts lead to more conflict? If so, why and under what conditions? And what can we do about it?

Dissertation Synopsis

If warming is increasing the likelihood of violence, two approaches will be necessary to mitigate climate change’s most hostile effects. First, we need to understand the causal mechanisms, identifying links in the causal chains that connect climate to conflict. Policymakers can then craft effective interventions that block one or more of those links. Second, we need to identify the moderators that enhance or suppress the influence of climate on conflict. Policymakers and administrators can then more effectively determine the countries, regions or individuals that are most vulnerable to climate-related violence. Together, they can optimally target those interventions towards those most vulnerable areas or individuals. The combination of effective policy, informed by greater knowledge of causal mechanisms, and effective targeting, informed by increased understanding of effect moderators, can successfully reduce the likelihood that climate change leads to violence.

My dissertation, “Climate, Social Order and Social Protection: Mechanisms and Moderators in Climate-Related Violent Conflict,” is composed of three separate but thematically related studies. It seeks to better elucidate both moderators and mechanisms in climate-conflict relationships, particularly those involving local-level social relations and institutions, and national-level social insurance policies. Specifically, my dissertation explores 1) whether trust and social capital moderate temperature’s influence on conflict across 33 countries in Africa, 2) whether climate stress is more likely to lead to conflict or cooperation in northern Namibia and 3) whether a programmatic social safety net policy in Ethiopia can block links in the causal chain from climatic stress, to economic hardship, to violence. Collectively, these studies provide novel empirical tests of a set of notable factors – suggested by the literatures on political and economic development, social capital, political economy of conflict, and climate resilience – that may moderate or explain the influence of climatic factors on conflict in countries in the Global South.

Job Market Paper: Link

Temperature, Conflict and Social Capital in Africa

Revise and Resubmit at the Journal of Peace Research

Abstract:

Aggregate estimates indicate that higher temperatures increase violence and conflict, yet existing evidence suggests these mean effects may obscure enormous heterogeneity. I theorize that social capital will significantly moderate the effect of temperature on conflict, by enhancing resilience to adverse climatic conditions and either suppressing or exacerbating the likelihood of violence under climate stress, depending on context. I test these theoretical propositions with geolocated survey data on trust, associational membership, community activity and contact with local leaders from 2800 grid-cell areas in 33 African countries. Social capital is strongly and robustly associated with a more negative temperature-conflict relationship. Specific measures of bonding, bridging and linking social capital all show this association. Moreover, tests with increasingly plausible identifying assumptions indicate that social capital, especially involving trust, reduces temperature’s conflict-enhancing effects. These results point to increasing social capital as an important tool for reducing the likelihood of violence as the climate warms.

Climate and Cooperation: Evidence from Namibia

Joint with Dylan W Groves (Lafayette College)

Working Paper: Available upon Request

Political outcomes ranging from mass migration to leadership change to violent conflict have been linked to adverse climatic conditions associated with climate change. While large scale cross-country panel datasets can provide substantiation of such relationships, relatively little rigorous evidence is available to identify micro-level behavioral and collective responses that could help to explain these links. In this paper we explore the micro-level impact of climate change by pairing an exogenous climatic shock – a severe and spatially-varying drought – with "lab-in-the-field" behavioral games and surveyed measures of collective action from ≈ 1000 livestock managers in 123 grazing areas across northern Namibia. First, we leverage repeated measurements of the same livestock managers over time to test whether play in public goods games differs between drought and non-drought conditions. Second, in the same villages, we explore how observed measures of collective behavior, including participation in water resource management and community grazing institutions, vary with the experience of drought. Initial results provide evidence that, in this context of acute vulnerability to climate change, severe climatic shocks tend not to affect or to increase people’s propensity to act pro-socially and collectively. Where present, such counter-veiling collective responses to the devastation of drought may enhance resilience in the face of climate change and limit the rise of disruptive future political outcomes, including mass migration to conflict.

Rainfall Time Series and Data Collection Timeline by Region

Can Social Safety Nets Prevent Climate-Related Conflict?  Evidence from Ethiopia

Early-Stage Conference Paper: Available upon Request, with Caveats

Abstract:

Few proposed causal mechanisms that could link climatic conditions to violent conflict are yet well understood or thoroughly tested. One commonly suggested mechanism is that of “opportunity cost.” When adverse climatic conditions reduce incomes and lead to livelihood loss, the opportunity cost of joining in violent, rebellious activity is reduced and the quantity of that activity rises accordingly. I explore the efficacy of an internationally funded and supported policy – Ethiopia’s Productive Safety Net Program (PSNP) – at reducing the link between climate and conflict in a context where livelihoods are heavily dependent on rainfall and temperature but climatic shocks (e.g. droughts) are common. The PSNP provides cash transfers to needy households and public works jobs to the underemployed. These outlays should break the opportunity cost mechanism, keeping individuals’ opportunity cost for violence high even while experiencing adverse climatic shocks. I exploit exogenous variation in climatic conditions like temperature and precipitation along with detailed, geographically precise and time-varying information on the PSNP program to test the role of the program in managing climate’s impact on violence. Very preliminary results suggest that, at least, the PSNP does little to exacerbate existing concerns with climate-driven insecurity. Coupled with other demonstrated benefits of this and other social safety net programs, a do-no-harm outcome, if it holds up to additional scrutiny, would be a positive result. Further results will provide new insights into whether “opportunity cost” is a major mechanism behind climate-conflict links in Ethiopia and shed new light on whether programmatic policies can break such links to prevent increases in conflict under a changing climate.

Temperature and Civil War: Differentiating Effects on Onset, Continuation and Termination

Working Paper: Available upon Request

While the burgeoning literature on climate and conflict has provided many insights and allowed scholars and practitioners to better gauge impacts of and plan for a changing climate, a number of features have been under-developed. Too often many different types of violent events have been pooled together, without consideration of the specific types of processes that might lead to these events.

This study seeks to improve upon existing limitations in the climate-conflict literature and push this growing area of scholarship in a number of ways. First, it considers a certain, particularly important, type of conflict event: civil war. Second, it separately considers theoretically distinct phases of civil wars: their start or “onset,” their "continuation," and their conclusion or “termination.” Finally, it begins to develop more explicit theory to explain why features of the climatic system might be related to particular types of harmful conflict events.

Broadly speaking, it finds that even for a very clearly defined large-scale event type: civil war, climatic variables play a role. Following prior work in the scholarship on civil war, after focusing in on the more civil war-prone, poorer, subset of national states, it finds that higher temperatures in a prior year are associated with a higher propensity for civil war onsets. The effects of temperature on civil war continuation are more ambiguous, while effects on termination tentatively suggest that temperature spike are associated with ends to civil wars in the following year.