Mispricing Climate Risk: Impacts on Property Insurance and Mortgages

A recent study by Wharton professor Parinitha Sastry, with co-authors Ishita Sen and Ana-Maria Tenekedjieva, explores the mispricing of climate risk within the property insurance and mortgage sectors. Their paper, “When Insurers Exit: Climate Losses, Fragile Insurers, and Mortgage Markets,” awarded the 2025 Marshall Blume Prize in Financial Research, highlights taxpayer liabilities and excess credit allocations to high-risk regions. This study underscores significant issues stemming from pricing inaccuracies.

The research focuses on the underestimation of climate-related risks in financial products. Professor Sastry has long been investigating the connection between climate risk, insurance, and mortgage markets. She points out that natural disasters expose the fragility of insurance coverage, complicating recovery efforts and straining the mortgage sector when insurers become insolvent. The study emphasizes that as climate-related losses escalate, they pose a growing threat to insurers' financial stability.

A key finding is the disconnect between actual risk levels and the rates applied to mortgages and insurance premiums. Such misalignment disturbs the risk signals essential for financial markets, inadvertently elevating the exposure of both lenders and homeowners to climate-related threats. Moreover, the research identifies characteristics contributing to insurer fragility, including insufficient capital, limited diversification, and reliance on poor-quality reinsurance, which lead to high insolvency rates.

Given these findings, Sastry advocates for policymakers, especially agencies like Fannie Mae and Freddie Mac, to implement stricter screening protocols for insurers. This would protect institutional exposures and enhance consumer protection as climate risks intensify. Further research is recommended to deepen the understanding of the interplay between insurance, housing, and real estate markets to better address these risks.