The Uncertainty Contagion: Revealing the Interrelated, Cascading Uncertainties of Managed Retreat

Christina Hanna,Iain White,Bruce Glavovic

doi:10.3390/su12020736

Abstract

Managed retreat presents a dilemma for at-risk communities, and the planning practitioners and decisionmakers working to address natural hazard and climate change risks. The dilemma boils down to the countervailing imperatives of moving out of harm’s way versus retaining ties to community and place. While there are growing calls for its use, managed retreat remains challenging in practice—across diverse settings. The approach has been tested with varied success in a number of countries, but significant uncertainties remain, such as regarding who ‘manages’ it, when and how it should occur, at whose cost, and to where? Drawing upon a case study of managed retreat in New Zealand, this research uncovers intersecting and compounding arenas of uncertainty regarding the approach, responsibilities, legality, funding, politics and logistics of managed retreat. Where uncertainty is present in one domain, it spreads into others creating a cascading series of political, personal and professional risks that impact trust in science and authority and affect people’s lives and risk exposure. In revealing these mutually dependent dimensions of uncertainty, we argue there is merit in refocusing attention away from policy deficits, barrier approaches or technical assessments as a means to provide ‘certainty’, to instead focus on the relations between forms of knowledge and coordinating interactions between the diverse arenas: scientific, governance, financial, political and socio-cultural; otherwise uncertainty can spread like a contagion, making inaction more likely.

Highlights

The projected impacts of climate change combined with legacy development and urbanization means that more people and assets will be exposed to natural hazard risks over the coming decades
While the managed retreat dilemma is typically positioned between the compelling scientific risk reduction imperative and substantial political unpalatability, in this paper, we seek to reframe this dilemma as involving more complex relations between multiple intersecting uncertainties, which we argue provides deeper explanatory power and new insights about its potential resolution
The potential of managed retreat is hampered by concatenated uncertainties that can only be addressed if they are identified [27], but they need to be considered in relation to each other and addressed across different arenas—from the techno-scientific to governance, financial, spatio-temporal and socio-cultural—in a coordinated manner

Summary

Introduction

The projected impacts of climate change combined with legacy development and urbanization means that more people and assets will be exposed to natural hazard risks over the coming decades Some of these risks can be calculated and managed effectively, in the short and medium term, by technical approaches designed to protect people and assets. Managed retreat can be defined as a deliberate strategy to remedy unsustainable land use patterns that expose people, ecosystems, and assets to significant natural (and socio-natural) hazard and climate change induced risks [8] The benefits of this strategy stretch beyond risk management to include the restoration of land and ecosystem functions, and the removal of long-term risk management liabilities and emergency management costs. It holds potential to create more equitable and sustainable outcomes compared to ad-hoc, reactive or unmanaged relocations, such as those associated with migration and displacement, or in comparison to at-risk communities remaining in situ but subjected to an uncertain future with the prospect of escalating risk and declining investment

Methods

Discussion

Conclusion