Climate-driven Arctic coastline modeling: improving erosion forecasts for communities
Investigators
Student
- Kristopher Carroll, MS program
Synopsis
The rapidly warming Arctic is leading to increased rates of coastal erosion, placing hundreds of Alaska communities at the frontline of climate change. Understanding current rates of coastline change and accurately forecasting future changes is critical for communities to mitigate and adapt to these changes. Current modeling approaches typically use a simple linear model based solely on historical coastline positions to measure rates of change and extrapolate them into the future. In doing so, these models fail to capture the dynamic effects associated with decreasing sea ice, increasing annual wave energy, and increasing temperatures. Given the number of communities threatened by rising rates of erosion, there is a need to expand the scope of these models and improve their quality.
This proposal has three main objectives:
1. Develop automated processing techniques to incorporate satellite imagery data into state-of-the-art Arctic coastal erosion models.
2. Generate coastline location forecasts for a selected at-risk Alaska community through the year 2100 using satellite imagery and downscaled climate data.
3. Engage with stakeholders and communities to co-produce the knowledge, improving the quality of the models and ensuring that research findings are of direct benefit to them.
Overview
The issue
The rapidly warming Arctic is leading to increased rates of coastal erosion, placing hundreds of Alaska communities at the frontline of climate change. Understanding current rates of coastline change and accurately forecasting future changes is critical for communities to mitigate and adapt to these changes. Current modeling approaches typically use a simple linear model based solely on historical coastline positions to measure rates of change and extrapolate them into the future. In doing so, these models fail to capture the dynamic effects associated with decreasing sea ice, increasing annual wave energy, and increasing temperatures. Given the number of communities threatened by rising rates of erosion, there is a need to expand the scope of these models and improve their quality.
Why is this an Alaska Sea Grant project?
The work proposed will directly contribute to the 2018-2021 Alaska Sea Grant Strategic Plan for Healthy Coastal Ecosystems (Goal 1), Resilient Communities and Economies (especially Goal 4), and Environmental Literacy and Workforce Development (especially Goal 7). Our research will contribute to both of the objectives within Goal 1, by co-producing improved knowledge and forecasts of coastal erosion for communities at risk. These results will also contribute to the objective of Goal 4 by increasing the capacity of communities and residents to adapt and respond to environmental changes and coastal hazards. Lastly, we will contribute to Goal 7 by expanding the Alaska workforce through undergraduate and graduate training.
Undergraduate researchers will be trained in satellite imagery acquisition and processing, and a graduate student will be trained in coastal erosion models and machine learning techniques.
How will researchers conduct their study?
We will work with stakeholders to select a community to co-produce improved coastal erosion models. These models will create new historical coastlines from satellite imagery and fieldwork using Global Navigation Satellite System (GNSS) devices operated in partnership with community members. These coastlines will be combined with newly downscaled climate data (e.g. temperature, sea ice, wind) and used as inputs to a nonlinear Gaussian process regression model. We have implemented a version of this approach on portions of the North Slope of Alaska and have found considerable improvements in the accuracy of the forecast coastline.
