Public understanding of climate change-related sea-level rise

RESEARCH ARTICLE Public understanding of climate change- related sea-level rise Rebecca K. PriestleyID1*, Zoe¨ Heine1, Taciano L. MilfontID2 1 Centre for Science in Society, Victoria University of Wellington, Wellington, New Zealand, 2 School of Psychology, The University of Waikato, Tauranga, New Zealand * rebecca.priestley@vuw.ac.nz Abstract Sea-level rise resulting from climate change is impacting coasts around the planet. There is strong scientific consensus about the amount of sea-level rise to 2050 (0.24–0.32 m) and a range of projections to 2100, which vary depending on the approach used and the mitigation measures taken to reduce carbon emissions. Despite this strong scientific consensus regarding the reality of climate change-related sea-level rise, and the associated need to engage publics in adaptation and mitigation efforts, there is a lack of empirical evidence regarding people’s understanding of the issue. Here we investigate public understanding of the amount, rate and causes of sea-level rise. Data from a representative sample of New Zealand adults showed a suprising tendency for the public to overestimate the scientifically plausible amount of sea-level rise by 2100 and to identify melting sea ice as its primary causal mechanism. These findings will be valuable for scientists communicating about sea- level rise, communicators seeking to engage publics on the issue of sea-level rise, and media reporting on sea-level rise. Introduction Between 1902 and 2015, global sea level rose by 16 cm [1]. In recent decades sea-level rise has

been accelerating, due to increasing rates of ice loss from the Greenland and Antarctic ice sheets. The majority of the world’s large cities are located on the coasts, and by 2050 one billion people could be at risk of coastal inundation or high-tide flooding [1]. While public under- standing of climate change has been well canvassed in recent years [2–5], public understanding of sea-level rise is relatively unexplored. Studies conducted in the United States and the United Kingdom show the public does not feel well informed about, and has difficulty understanding, sea-level rise associated with cli- mate change [6, 7]. Moreover, a review of international sea-level rise communication [8] noted sea-level rise has suffered from low media attention and salience as a public issue. This lack of public understanding and salience as an issue is despite the fact that sea-level rise is already causing increased coastal flooding [9], and there is relatively low uncertainty about the amount of sea-level rise that will occur to 2050, which is projected to be between 0.24 and 0.32 m [10]. (Sea-level rise is always counted with respect to a reference date: in this paper we have PLOS ONE PLOS ONE | https://doi.org/10.1371/journal.pone.0254348 July 9, 2021 1 / 12 a1111111111 a1111111111 a1111111111 a1111111111 a1111111111 OPEN ACCESS Citation: Priestley RK, Heine Z, Milfont TL (2021) Public understanding of climate change-related sea-level rise. PLoS ONE 16(7): e0254348. https:// doi.org/10.1371/journal.pone.0254348 Editor: Riccardo Riva, Technische Universiteit Delft, NETHERLANDS

Received: November 24, 2020 Accepted: June 25, 2021 Published: July 9, 2021 Copyright: © 2021 Priestley et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Data Availability Statement: The full sea-level rise survey, as well as overall descriptive results produced by Horizon Research, and the raw data, can be found in the Open Science Framework: https://osf.io/vcjuf/. Funding: RKP and ZH: Supported by New Zealand Ministry of Business, Innovation, and Employment Grant through Victoria University of Wellington (RTUV1705), NZ SeaRise Programme administered by the Antarctic Research Centre. LM: Victoria University of Wellington sabbatical (222992). The funders had no role in study design,