As consensus on the existence of global climate change has grown over the past several decades, debate has shifted to the consequences of climate change. The collective work of social scientists offers a varied picture of the ways in which climate change may impact humans. Attempts to draw clear linkages between climate change and human events, however, have proven challenging and contentious. Although difficult to unpack, the implications climate change may have for human rights and conflict are particularly important to understand given the gravity of those issues. This study will attempt to help elucidate the impact of climate change on human rights and conflict. By drawing on relevant scientific, social science, and legal literature, I intend to show that climate change can cause conflict and, consequently, poses a real threat to protection of human rights. The essay will proceed in four parts. First, I will briefly summarize existing scientific data on climate change, including projections of how it will affect the planet in the future. Second, I will examine the ways in which climate change can cause conflict. Third, I will discuss what role, if any, international humanitarian law, international human rights law, and international justice can play in defending against climate change-related infringements on human rights. Last, I will conclude with some general thoughts about the utility of a human rights approach to climate change.

I.  The Science of Global Climate Change Global Warming Earth’s average temperature has increased by 0.8 degrees Celsius over the past 100 years.[i]  Twenty of the warmest years on record occurred between 1981 and 2008.  Ten of these were recorded between 1996 and 2008.[ii]  Future projections of global temperatures point to the likely intensification of current trends.  The Intergovernmental Panel on Climate Change (IPCC) relates that, “It is virtually certain that increases in the frequency and magnitude of warm daily temperature extremes and decreases in cold extremes will occur in the 21st century at the global scale.”[iii]  More specifically, the IPCC estimates that depending on global greenhouse gas emissions, temperatures will rise somewhere between 1.1 and 6.4 degrees Celsius over the course of the 21st century.[iv] Altered Weather Patterns The rise in global temperatures is expected to alter existing weather patterns during the 21st century, significantly affecting human life.  Observed and expected changes to weather patterns can be classified in five categories: (1) sea ice melting and a reduction in land areas covered by snow; (2) rise in sea levels and warmer water temperatures; (3) more frequent heat waves; (4) intense precipitation and larger areas affected by drought; and (5) more intense hurricanes.[v]  The IPCC projects that these changing weather patterns will impact health, water, food, and coastlines, among other areas.  For instance, the IPCC notes that the continued rise of sea levels will lead to “extreme sea levels” that could inundate the coasts of small island states.[vi] The Worst Affected The countries that will experience the most drastic changes in climate are likely to be the world’s poorest.[vii]  For example, the International Food Policy Research Institute asserts that climate change will most impact food security in the Middle East and North Africa and Sub-Saharan Africa, two of the world’s poorest regions.[viii]  This finding is consistent with the IPCC’s suggestion that droughts in West Africa have become longer and more intense, and promise to increase in intensity in the future. Summary Climate change stresses the key human needs for food, water, and shelter.  Furthermore, it indicates that the world’s poorest countries, which already struggle to meet these basic needs, will suffer the most from climate-related stresses.  Taken together, these phenomena beg the question of whether climate change can place enough stress on states or individuals to cause conflict. II.  Can Climate Change Cause Conflict? A Challenging Question The role climate change plays in conflict, if any, is a challenging and hotly contested issue.  Views on the role climate change plays in conflict span the spectrum from no role to a primary cause.  Part of the reason why there is such a wide range of opinions is the fact that identifying a link between climate change and conflict requires exposing secondary and tertiary consequences of climate change.  Climate change is not a new technology or weapon that can be used by states or non-state actors to target armies or civilians; it is a global problem to which every state and every person on Earth contributes, albeit to different degrees.  Moreover, because traditional sources of conflict are as numerous as they are diverse—and consequently often difficult to pinpoint—adding climate change to the mix can sometimes make for an even murkier conflict picture. Methodology In order to mitigate these challenges, this essay balances a review of broad studies of the potential relationship between climate change and conflict with regional and country-specific case studies.  When possible, drawing distinctions between instances in which climate change is associated with conflict, a contributing factor to conflict, and a primary cause of conflict is also important.  This study utilizes these sources and classifications to draw conclusions on how, if at all, the stress climate change places on basic human needs plays a causal role in conflict.  The following potential causes of conflict, which are often interrelated, are analyzed because of their association with the basic human needs of food, water, and shelter: migration, rising sea levels, food insecurity, and water scarcity. Migration Migration can be associated with rising sea levels, food insecurity, and water scarcity.  The UN Human Rights Council identifies “four main climate change-related displacement scenarios, where displacement is caused by: weather-related disasters, such as hurricanes and flooding; gradual environmental deterioration and slow onset disasters, such as desertification, sinking of coastal zones and possible total submersion of low-lying island States; increased disaster risks resulting in relocation of people from high-risk zones; [and] social upheaval and violence attributable to climate change-related factors.”[ix]  Etienne Piguet et al. echo these risk categories, focusing on cyclones, heavy rains, and floods; drought and desertification; and sea-level rise.[x] Estimates of the human impact of this association, however, vary significantly.  The IPCC’s First Assessment Report, for example, predicted that climate change would forcibly displace approximately 150 million people by 2050.[xi]  Recent studies have offered more dire predictions.  The Stern Review on the Economics of Climate Change predicts that 200 million people will be forced to migrate over the same period due to the effects of climate change.[xii]  A Christian Aid study estimates that there will be 250 million climate-induced migrants by 2050.[xiii] Others provide a more cautious assessment of the role climate change plays in migration.  Piguet et al. note: "Climate change is clearly a complex environmental process that does not have uniform consequences everywhere; and societies have always had to adapt to changing environmental contexts – a multifaceted process of technological, organizational, institutional, socio-economic, and cultural nature that is likely to be just as complex as climate change itself.  The number of variables is therefore important, leading to high uncertainty and local variability."[xiv] Piguet et al., therefore, suggest that the climate change-migration link is less pronounced and impactful with respect to cyclones and water scarcity than the IPCC, Stern Review, and Christian Aid projections.[xv]  Nevertheless, Piguet et al. predict that approximately 146 million people will become “directly vulnerable” within several decades to rising sea levels.  Sea level rise due to climate change, they argue, represents the “clearest threat in terms of long-term forced migration.”[xvi] These studies suggest that climate change will play an increasing role in human displacement in the coming decades.  The challenge of pinpointing the degree to which climate change is responsible for any given incident of migration should not distract from the nature of the threat.  Neither should the difficulty in projecting exactly how many people will be forced to migrate by climate change during the 21st century be cause for complacency.  The fact that an estimate of tens of millions of climate change-related migrants could be considered conservative should be ample cause for alarm. Can Migration Cause Conflict? Globally, there have already been a number of states in which migration due to climate change-driven water scarcity escalated, renewed, or created fresh violent conflict. Migration in Tanzania’s water-stressed Pangani River basin, for example, is believed to have contributed to an escalation of local water conflicts.[xvii]  In Yemen, one of the most water-scarce countries in the world, inter-tribal conflict is strongly associated with land or water issues.[xviii]  Similarly, Gergana Yancheva et al. conclude that migration due to climate change-related famine in China and Central America led to conflict that played a contributing role in the decline of the Tang dynasty and the Classic Maya.[xix] Climate change-driven drought also appears to have resulted in conflict along the borders of Kenya, Sudan, Ethiopia, and Uganda.[xx]  The International Organization for Migration (IOM) relates that due to a “high variation in rainfall,” for which climate change is a “key driving factor,” “pastoralists are forced to move frequently to exploit available resources between seasons.  This has caused growing cross-border, resource-based armed conflicts.”[xxi]  The IOM classifies these conflicts as a “major security challenge in East Africa.”[xxii] The IOM also characterizes climate change as a contributor to intrastate conflict in Sudan.  In its words: "Although not the main driver of the crisis that has been devastating Sudan for many years, conflict between pastoralists and sedentary groups over scarce land suitable for grazing livestock or growing crops has been among the contributing factors to this complex situation. This type of conflict, while not new, has the potential to escalate, in light of the effects of long-term climate change.  A decade-long decline in rainfall has badly degraded much previously fertile land, dramatically reducing many areas’ ability to support human life and livelihoods."[xxiii] In short, climate change is playing a contributing role in intrastate conflict in Sudan and has the potential to play a more primary role in the future. Broader Trends in Climate Change-Driven Conflict These individual cases parallel evidence for broader trends in climate change-driven conflict.  For example, African civil wars, “defined as the use of armed force between 2 parties, one of which is the government of a state, resulting in at least 1,000 battle-related deaths,” are strongly linked to rising temperatures.  More specifically, a temperature increase of 1 degree Celsius in any given year has historically lead to a 4.5% increase in the number of civil wars that year and a 0.9% increase in number of conflicts in the following year.[xxiv]  Based on this climate change-conflict relationship and current trends in temperature, climate change is projected to lead to an additional 393,000 battle deaths in Africa by 2030, not including deaths indirectly related to the war.[xxv]  The evidence that agricultural performance related to climate change is the “central mechanism linking warming to conflict in Africa”[xxvi] mirrors the IOM’s perspective on conflicts in Sudan, Kenya, Ethiopia, and Uganda, as well as Gergana Yancheva et al.’s view on the dissolution of the Tang Dynasty and the Classic Maya. III.  Can Human Rights Law and International Justice Help? The Role of International Humanitarian Law International Humanitarian Law (IHL) can play a useful role in advancing protection of civilians in climate change-related conflicts involving state or government forces.  Articles 48, 51, 57 and 58 in Additional Protocol I are particularly important.  Article 48 of Additional Protocol I states: “The Parties to the conflict shall at all times distinguish between the civilian population and combatants and between civilian objects and military objectives and accordingly shall direct their operations only against military objectives.”[xxvii]  Article 51 requires proportionality in war, particularly the prohibition of indiscriminate attacks, collateral damage to civilians in excess of military advantage, and reprisals.[xxviii]  Last, Articles 57 and 58 dictate that parties to the conflict must take precautions against harming civilians and their property from military operations.[xxix]  IHL, the Guiding Principles on Internal Displacement, and international refugee law, specifically the 1951 Convention Relating to the Status of Refugees and the Convention Governing the Specific Aspects of  Refugee Problems in Africa, can also help protect refugees or internally displaced persons of climate change conflicts.[xxx] IHL’s ability to promote protection is, however, also constrained by two factors.  Since states are more likely to abide by IHL provisions than non-state actors, civilians may suffer disproportionately in climate change-related conflicts between non-state groups.  More importantly, because climate change is not a tool of war, IHL provides no defense against the climate change-related stresses that cause conflict. The Role of International Human Rights Law International Human Rights Law (IHRL) can play a limited preventative role in climate change-related conflict.  The International Covenant on Civil and Political Rights (ICCPR) and the International Covenant on Economic, Social and Cultural Rights (ICESCR) are the most relevant IHRL tools for advancing the enjoyment of human rights threatened by climate change.  Their protections of the right to life, the right to adequate food, the right to water, the right to health, the right to adequate housing, and the right to self-determination are particularly important.[xxxi]  Successful protection of these rights by governments ensures the absence of the climate change-related stresses that cause conflict. In practice, however, IHRL’s ability to pressure governments to protect these rights will be limited.  Even though every government that is a signatory to the ICESCR is obligated to ‘respect, protect and fulfill’ ICESCR rights[xxxii], failure to do so is unlikely to constitute a legal violation of human rights given the secondary and tertiary nature of climate change’s effect on human rights.[xxxiii]  Furthermore, because climate change disproportionately affects already marginalized and vulnerable groups in states, it seems unlikely that states will focus on protecting these groups in the short run.  Perhaps in the long run, however—if the role climate-related stress plays in conflict becomes clearer—states will invest more resources in defending these basic human rights. The Role of International Justice Aside from advancing the accountability of parties responsible for human rights violations during climate-related conflict, international justice appears likely to play only a minor role in climate change-related protection for the foreseeable future.  As noted previously, it is extremely difficult to bring legal pressure on governments to protect ICCPR and ICESCR rights threatened by climate change.  Similarly, efforts to prosecute corporations for their contribution to climate change-related infringements on human rights have failed at the International Criminal Court.  Such claims seem likely to continue to fail because of the difficulty of attribution and providing direct evidence of egregious human rights violations.[xxxiv] International justice will likely be more effective in pressuring governments to ensure that their responses to climate change do not infringe on human rights.  Daniel Bodansky explains that, “When a government acts to combat climate change, it must do so in ways that respect human rights.  In this regard, measures to combat climate change are no different from measures to combat terrorism or crime.”[xxxv]  For example, international justice could be used to hold a government accountable for threatening food security by responding to climate change through greater reliance on bio-fuels.  As of yet, however, few such cases have been tried in international justice bodies. IV.  Conclusion Climate change is a dangerous global phenomena that preys on the vulnerable and poses a significant threat to the protection of human rights.  Not only can climate change play a causal role in violent conflict, it also threatens the enjoyment of ICCPR and ICESCR human rights.  Given current global warming trends, moreover, climate change-related stresses appear likely to intensify over the course of the 21st century.  This likelihood implies an increased frequency of climate change-related conflicts in the future. Solving global climate change will of course necessitate more than a human rights approach has to offer.  Policy will surely play an important role.  More specifically, binding international agreements to limit greenhouse gas emissions will likely be required. Nevertheless, with the danger of climate change increasing and policy solutions appearing unlikely in the near future, it is prudent to leverage human rights tools, however limited they may be, to help mitigate the consequences of climate change.  IHL will be vital to advancing protection in conflict situations emanating from climate change, particularly those involving government forces.  IHRL will be most useful if it can be combined with international justice as a tool for shaping government responses to climate change, and compelling responses when necessary.  If done successfully, IHRL even has the potential to play a significant preventative role in climate change-related conflict.  Clearly, in the absence of a global solution to climate change, a human rights approach to climate change will be key to protection.

[i] “Climate Change Basics,” United States Environmental Protection Agency, 14 June 2012 http://www.epa.gov/climatechange/basics/.
[ii] T.C. Peterson et.al., “State of the Climate in 2008,” Special Supplement to the Bulletin of the American Meteorological Society, 90:8 (Aug. 2009): S18.
[iii] IPCC, Managing the Risks of Extreme Events and Disasters to Advance Climate Change Adaptation: Summary for Policymakers (Cambridge: Cambridge University Press, 2012) 11.
[iv] IPCC, Chap. 10: Global Climate Projections, Sec. 10.ES: Mean Temperature, Climate Change 2007: The Physical Science Basis (Cambridge: Cambridge University Press, 2007).
[v] U.N. Human Rights Council, 10th Session.  Report of the Office of the United Nations High Commissioner for Human Rights on the Relationship between Climate Change and Human Rights (A/HRC/10/61) 15 Jan. 2009: 5.
[vi] IPCC, Managing the Risks of Extreme Events and Disasters to Advance Climate Change Adaptation: Summary for Policymakers (Cambridge: Cambridge University Press, 2012) 16-17.
[vii] International Council on Human Rights Policy, Climate Change and Human Rights: A Rough Guide (Vernier, Switzerland: ATAR Roto Press SA, 2008) 1.
[viii] Nicholas Magnum, “Which Regions Will Be Most Affected by Climate Change?” International Food Policy Research Institute, 1 Dec. 2010 http://www.ifpri.org/blog/which-regions-will-be-most-affected-climate-change.
[ix] U.N. Human Rights Council, 10th Session.  Report of the Office of the United Nations High Commissioner for Human Rights on the Relationship between Climate Change and Human Rights (A/HRC/10/61) 15 Jan. 2009: 19.
[x] Etienne Piguet et al., “Migration and Climate Change: An Overview,” Refugee Survey Quarterly, 30:3 (June 2011) 7-12.
[xi] U.N. Human Rights Council, 10th Session.  Report of the Office of the United Nations High Commissioner for Human Rights on the Relationship between Climate Change and Human Rights (A/HRC/10/61) 15 Jan. 2009: 18.
[xii] Nicholas Stern, Stern Review on the Economics of Climate Change (Cambridge: Cambridge University Press, 2006) http://webarchive.nationalarchives.gov.uk/+/http:/www.hm-treasury.gov.uk/sternreview_index.htm.
[xiii] Christian Aid, Human Tide: The Real Migration Crisis (2007).
[xiv] Etienne Piguet et al., “Migration and Climate Change: An Overview,” Refugee Survey Quarterly, 30:3 (June 2011): 13.
[xv] Piguet et al. 7-11.
[xvi] Piguet et al. 12.
[xvii] Milline J. Mbonile, “Population, Migration, and Water Conflicts in the Pangani River Basin, Tanzania.” ECSP Report Issue 12.  Woodrow Wilson International Center for Scholars 2006-2007: 20
[xviii] Stefan Lindemann, “Addressing the Need for Water Service Delivery in Fragile States: The Case of German Donor Involvement in Yemen” 2006 Berlin Conference on the Human Dimensions of Global Environmental Change (17-18 Nov. 2006).
[xix] Gergana Yancheva et al., “Influence of the Intertropical Convergence Zone on the East Asian Monsoon,” Nature 445 (Jan. 2007) 74-77.
[xx] International Organization for Migration, Compendium of IOM’s Activities in Migration, Climate Change and the Environment (Geneva: International Organization for Migration, 2009) 145.
[xxi] International Organization for Migration 92.
[xxii] International Organization for Migration 145.
[xxiii] International Organization for Migration, Compendium of IOM’s Activities in Migration, Climate Change and the Environment (Geneva: International Organization for Migration, 2009) 128.
[xxiv] Marshall B. Burke et al., “Warming Increases the Risk of Civil War in Africa,” Proceedings of the National Academy of Sciences, 106:49 (Dec. 2009) 20670.
[xxv] Marshall B. Burke et al. 20672.
[xxvi] Marshall B. Burke et al., “Warming Increases the Risk of Civil War in Africa,” Proceedings of the National Academy of Sciences, 106:49 (Dec. 2009) 20672.
[xxvii] Article 48.  Protocol Additional to the Geneva Conventions of 12 August 1949, and relating to the Protection of Victims of International Armed Conflicts (Protocol I), 8 June 1977.
[xxviii] Article 51.  Protocol Additional to the Geneva Conventions of 12 August 1949, and relating to the Protection of Victims of International Armed Conflicts (Protocol I), 8 June 1977.
[xxix] Articles 57 and 58.  Protocol Additional to the Geneva Conventions of 12 August 1949, and relating to the Protection of Victims of International Armed Conflicts (Protocol I), 8 June 1977.
[xxx] U.N. Human Rights Council, 10th Session.  Report of the Office of the United Nations High Commissioner for Human Rights on the Relationship between Climate Change and Human Rights (A/HRC/10/61) 15 Jan. 2009: 21.
[xxxi] U.N. Human Rights Council 8-14.
[xxxii] International Council on Human Rights Policy, Climate Change and Human Rights: A Rough Guide (Vernier, Switzerland: ATAR Roto Press SA, 2008) 13.
[xxxiii] .N. Human Rights Council, 10th Session.  Report of the Office of the United Nations High Commissioner for Human Rights on the Relationship between Climate Change and Human Rights (A/HRC/10/61) 15 Jan. 2009: 23.
[xxxiv] International Council on Human Rights Policy 71.
[xxxv] Daniel Bodansky, “Introduction: Climate Change and Human Rights: Unpacking the Issues,” Georgia Journal of International and Comparative Law 38:3 (2010) 522.