Worst case scenario as stakeholder decision support: a 5- to 6-m sea level rise in the Rhone delta, France

Abstract

Risk policy and public attitudes appear disconnected from research predicting warmer climate partially due to human activity. To step out of this stalled situation, a worst case scenario of a 5-to 6-m sea level rise (SLR) induced by the collapse of the WAIS and occurring during the period 2030-2130 is constructed and applied to the Rhone delta. Physical and socio-economic scenarios developed with data from the Rhone delta context are developed and submitted to stakeholders for a day-long workshop. Group process analysis shows a high level of trust and cooperation mobilized to face the 5-6 m SLR issue, despite potentially diverging interests. Two sets of recommendations stem from the scenario workshop. A conservative "wait and see" option is decided when the risk of the WAIS collapse is announced in 2030. After WAIS collapse generates an effective 1 m SLR rise by 2050, decisions are taken for total retreat and rendering of the Rhone delta to its hydrological function. The transposition of these results into present-day policy decisions could be considered. The methodology developed here could be applied to other risk objects and situations, and serve for policy exercises and crisis prevention.

Coastal vulnerabilities under the deliberation of stakeholders: The case of two French sandy beaches

“…In order to make a choice that makes sense scientifically, politically and socially, they resource not only to scientific recommendations, but to a large extent to culturally shared ideas about the environment and risks (Adger et al, 2005;Delicado et al, 2012;Poumad ere et al, 2008). Let us now present a method to explore how more extreme and yet abstract decisions could be taken by stakeholders and policymakers under the pressure of an emergency situation.…”

Participatory analysis for adaptation to climate change in Mediterranean agricultural systems: possible choices in process design

“…At one extremity of the continuum, after the researchers present their previously prepared climate change and socio-economic scenarios, participants are invited to identify possible adaptation strategies. This approach allows the researchers to carefully design the scenarios and particularly to incorporate simulations based on climate models (Eakin et al 2007, Poumadère et al 2008, Thompkins et al 2008. It also allows researchers to think about how to communicate and how to assess simulations based on climate models with the participants (McCrum et al 2009).…”

“…This common ground usually ranges from 25 years ) to 50 years from the present (Eakin et al 2007). Another option is to progressively increase the time horizon of the scenarios discussed with the participants (Poumadère et al 2008).…”

Abrupt climate change near the poles

“…The authors also believe that some of the historical parts of London can be preserved in a "Venice of London", noting that the actual Venice is unlikely to survive. Poumadere et al (2008) study the Camargue, a nature reserve in the delta of the Rhone. Here as well, the likely decision is retreat although they argument is a different one.…”