Extreme weather events in New Zealand: Financial market-related impacts

Abstract

Purpose – The purpose of this paper is to investigate extreme weather event (EWE) financial impacts on New Zealand investors. Design/methodology/approach – This study analyzes trends in extreme rain, wind, temperature, snow, and convective events (thunderstorms) and conducts an event study of the share market impacts of those events. Findings – This paper documents relatively stable distributions of EWEs in New Zealand over the past several decades. NZ EWEs bear only limited resemblance to conventional measures of climate change. NZX50 share prices are mostly insensitive to EWEs. Research limitations/implications – The muted financial response of investors to NZ EWEs has implications for the mandatory disclosure of climate-related physical risks. Additional public disclosure of extreme weather risks may not improve stock market efficiency if investors may have already factored in much of the EWE physical risks into share market prices. Practical implications – This study offers relevant findings for investors and asset managers interested in adjusting their portfolios based on EWE risks. Social implications – This study raises questions about whether rules for mandatory climate-related disclosure of local EWE risks in New Zealand will improve investor decision-making and further global sustainable development goals. Originality/value – This study examines a novel EWE data set assembled and curated by experts at New Zealand’s MetService to study EWE financial impacts in New Zealand.