Influence of sea level rise on discounting, resource use and migration in small-island communities: an agent-based modelling approach

Abstract

SUMMARYTime discounting – the degree to which individuals value current more than future resources – is an important component of natural resource conservation. As a response to climate change impacts in island communities, such as sea level rise, discounting the future can be a rational response due to increased stress on natural resources and uncertainty about whether future generations will have the same access to the same resources. By incorporating systematic responses of discount rates into models of resource conservation, realistic expectations of future human responses to climate change and associated resource stress may be developed. This paper illustrates the importance of time discounting through a theoretical agent-based model of resource use in island communities. A discount rate change can dramatically change projections about future migration and community-based conservation efforts. Our simulation results show that an increase in discount rates due to a credible information shock about future climate change impacts is likely to speed resource depletion. The negative impacts of climate change are therefore likely to be underestimated if changes in discount rates and emerging migration patterns are not taken into account.

Agent-based modeling for migration and modern slavery research: a systematic review

“…Seven of the studies used time scales that reflected real historical or date ranges, primarily in years, such as Kniventon, Smith and Black's model on climate induced migration in Tanzania from 1970 to 1994 [60]. The remaining models that included clear explanations of time-steps (n = 4) represented these discrete increments as 'time-to-event' meaning that they represented distinct processes, such as farming seasons or migration cycles [51,53,56,57]. Spatial characteristics are often an important design decision in ABM and the spatial representation depends on the research aims and data available (See Table 7).…”

Why scientific information does not necessarily impact the decisions by human society

“…There are cognitive biases that make us focus on the present, leading to less concern for the future (temporal discounting). The evolutionary roots of this behavior would lie in the fact that life expectancy in the first hominids would be extremely short, leading them to strategies focused on the present and their most urgent needs (Penn 2003, Henry et al 2017. A catastrophic scenario tends to emerge when associating these cognitive biases with our current consumption patterns.…”

Heterogeneous sea-level rises along coastal zones and small islands

“…MSL is a measure of the sea level variations over time and presents the mean change in the sea-level anomaly (SLA) located in assigned longitude-latitude grids. The effects of SLR on small islands have been widely reported [18][19][20][21]. Indisputably, heterogeneous assessments of SLR changes need to consider the MSL, which includes the climate-change-driven global MSL [16] and local variations caused by the melting of glaciers, ice-caps, and mountain glaciers; ocean circulation patterns; ocean heat content [22][23][24]; interannual or decadal variability; glacial isostatic adjustment; and tectonic movement [25].…”