Flooded House or Underwater Mortgage? The Macrofinancial Implications of Climate Change and Adaptation

Abstract

I study how climate change affects housing markets, mortgage credit, and private adaptation in a general-equilibrium overlapping-generations model. Climate events damage housing and degrade land, which is inelastically supplied. While exposure to future climate risk lowers expected resale values, realized climate damages reduce effective housing supply, raising house prices over time. In frictionless markets, forward-looking prices support efficient adaptation. However, credit-constrained households underinvest in resilience, implying that price signals alone are insufficient. Unequal adaptation amplifies wealth inequality and accelerates land degradation, tightening credit constraints and widening the adaptation gap. I show that a shift toward landlord-based ownership can restore efficiency.

Keywords: Climate Change, Climate Change Adaptation, Housing, Financial Assets, Financial Constraints, Wealth Inequality, Flood Risk

JEL Classification: E44, G51, Q54