Paper: arXiv 2501.11552

Authors: Emilio Barucci, Daniele Marazzina, Aldo Nassigh

Abstract

We explore the interplay between sovereign debt default/renegotiation and environmental factors (e.g., pollution from land use, natural resource exploitation). Pollution contributes to the likelihood of natural disasters and influences economic growth rates. The country can default on its debt at any time while also deciding whether to invest in pollution abatement. The framework provides insights into the credit spreads of sovereign bonds and explains the observed relationship between bond spread and a country’s climate vulnerability. Through calibration for developing and low-income countries, we demonstrate that there is limited incentive for these countries to address climate risk, and the sensitivity of bond spreads to climate vulnerability remains modest. Climate risk does not play a relevant role on the decision to default on sovereign debt. Financial support for climate abatement expenditures can effectively foster climate adaptation actions, instead renegotiation conditional upon pollution abatement does not produce any effect.

Complexity vs Empirical Score

  • Math Complexity: 7.5/10
  • Empirical Rigor: 5.0/10
  • Quadrant: Holy Grail — high math complexity, high empirical rigor

Why this score: The paper presents a rigorous theoretical dynamic macroeconomic framework using jump-diffusion processes and stochastic optimal control to analyze sovereign default and climate risk. While the empirical aspect relies on calibration rather than an extensive empirical backtest, the quantitative model design and policy analysis are sophisticated and well-written.

Research Flowchart

  flowchart TD
    A["Research Goal: Analyze interplay between<br>sovereign default & climate risk"] --> B["Inputs: Macroeconomic data,<br>climate vulnerability & pollution factors"]
    B --> C["Methodology: Calibrate sovereign default model<br>with pollution abatement & renegotiation"]
    C --> D["Computational Process: Simulate default decisions,<br>credit spreads & abatement incentives"]
    D --> E["Findings: Climate risk has minimal impact on default;<br>low incentive for countries to abate pollution"]
    D --> F["Policy Outcomes: Direct financial support fosters adaptation;<br>conditional debt renegotiation is ineffective"]