处于风险边缘：评估蒙古的“合理最坏情况”情景

Policy Research Working Paper At the Edge of Risk Assessing Mongolia’s “Plausible Worst-Case” ScenarioPublic Disclosure Authorized Migle PetrauskaiteHector PollittXinru Lin Trade, Competition, and BusinessGlobal DepartmentMay 2026 Policy Research Working Paper11370 Abstract This paper develops a plausible worst-case scenario for Mon-golia in which three major disasters—a sudden collapsein coal exports to China, a prolonged dzud (severe winterdisaster), and a severe flood in Ulaanbaatar—occur inquick succession. While each event has precedent in Mon-golia, an increasingly unstable climate raises the likelihoodof their overlap within the next 20 years. Conventional of these three crises could result in a 20 percent negativeshock to annual gross domestic product over a three-yearperiod, severely disrupting output and employment. Thefindings underscore the need for policy decisions based onworst-case scenarios rather than mean projections, empha-sizing proactive adaptation measures to mitigate systemicrisks. The paper highlights key vulnerabilities and calls for This paper is a product of the Trade, Competition, and Business Global Department. It is part of a larger effort by theWorld Bank to provide open access to its research and make a contribution to development policy discussions around theworld. Policy Research Working Papers are also posted on the Web at http://www.worldbank.org/prwp. The authors maybe contacted at mpetrauskaite@worldbank.org and hpollitt@worldbank.org. A verified reproducibility package for this The Policy Research Working Paper Series disseminates the findings of work in progress to encourage the exchange of ideas about developmentissues. An objective of the series is to get the findings out quickly, even if the presentations are less than fully polished. The papers carry thenames of the authors and should be cited accordingly. The findings, interpretations, and conclusions expressed in this paper are entirely thoseof the authors. They do not necessarily represent the views of the International Bank for Reconstruction and Development/World Bank and At the Edge of Risk: Migle Petrauskaite*, Hector Pollitt*, Xinru Lin* Keywords:climate risk, cascading disasters, scenario modelingJEL classification: D81; E17; Q51; Q54 1Introduction Mongolia is grappling with escalating climate change impacts, macro financial vulnerabilities, andan under-diversified export base, leaving it susceptible to simultaneous shocks. This paper exploresa ‘plausible worst-case’ scenario where a series of catastrophic events unfolds in rapid succession.It is informed by the risk-based, actuarial approach to climate change and compound shocks Severe climate-related impacts are already materializing at lower temperature increases thanpreviously expected (Ripple and others 2023). As a result, historical ‘tail’ risks—low-probability buthigh-impact events—are becoming more plausible. A growing body of academic literature highlightsthat such risks often occur in combination rather than isolation, with their interactions amplifyingeconomic and social impacts. For example, Zscheischler and others (2020) develop a widely used Recent observations suggest that the world is rapidly approaching, if not already surpassing, the1.5°C temperature threshold (Armstrong McKay and others 2022). Compounding this is newevidence that Earth’s climate sensitivity may be higher than expected, implying that future warmingcould be more severe for any given concentration of greenhouse gases. The precise degree of As we near 1.5°C warming, the risk of concurrent climate shocks increases. This paper examines thepotential impact of negative tail outcomes. In complex systems, including both our naturalenvironment and economies, such tail outcomes are more probable than conventional modelssuggest (see e.g., Beinhocker 2007). Because models reflect their underlying assumptions, failing to We focus on a scenario involving three increasingly plausible events: China halting its imports ofMongolian coal, a dzud (a harsh winter disaster), and a severe urban flood—all occurring over ahypothetical three-year period. While these three events are not equally likely, the probability of their higher than the simple multiplication of each individual event’s probability. An unstable climate Although this paper includes some quantitative analysis, its purpose extends beyond merelyprojecting GDP impacts from climate change. It seeks to identify critical vulnerabilities that climatechange could exacerbate. Effective climate policy must pay closer attention to tail risks. Traditionalmodels may understate the true threat by focusing on average outcomes. The more relevantquestion is:How bad could it get?By pinpointing vulnerabilities, we can better assess the proactive This paper considers the combined effect of the three crises and how the worst-case outcomescould be avoided. In Section2, we analyze each of the three adverse events, while Section3p