Climate Economics Seminar: Mitigation and Adaptation for Coastal Impacts from Sea Level Rise
Date and TimeThursday 01/28/2016 3:00PM to 4:30PM EST
POSTPONED!! Date TBD.
Coastal sector impacts from sea level rise (SLR) are a key component of the projected economic damages of climate change, a major input to decision-making and design of climate policy. Moreover, the ultimate costs to coastal resources will depend strongly on adaptation, society’s response to cope with the impacts. The first part of this talk presents a new optimization model to inform global estimates of coastal impacts, the Coastal Impact and Adaptation Model (CIAM). CIAM determines the optimal strategy for adaptation at the local level, evaluating over 12,000 coastal segments, as described in the DIVA database, based on socioeconomic characteristics and the potential impacts of relative sea level rise and uncertain sea level extremes. I will present a deterministic application of CIAM that demonstrates the model’s ability to assess local impacts and direct costs, choose the least-cost adaptation, and estimate global net damages for several climate scenarios that account for both global and local components of SLR (Kopp et al, 2014). CIAM finds large potential for coastal adaptation to reduce the expected impacts of SLR compared to the alternative of no adaptation, lowering global net present costs through 2100 by a factor of seven, although this does not include initial transition costs to overcome an under-adapted current state. In addition to producing aggregate estimates, CIAM results can also be interpreted at the local level, where retreat (e.g., relocate inland) is often a more cost-effective adaptation strategy than protect (e.g., construct physical defenses). The subsequent part of this talk presents related work exploring a specific climate threshold response, a potential disintegration of the West Antarctic Ice Sheet (WAIS). I will review the current scientific understanding of WAIS, identify methodological and conceptual issues related to incorporating threshold responses in integrated assessment models (IAMs), and demonstrate avenues to address some of them. Specifically, the threat of WAIS disintegration is represented in a stochastic hazard IAM framework (in an approximate way) that combines emulation of geophysical dynamics, expert knowledge, and learning. The DICE-WAIS model presented here is used to illustrate the relationships between scientific uncertainties, policy objectives, and economically-efficient strategies in the face of a specific climate threshold response.