Case Study: Monitoring Coastal Change via Satellite Imagery at Regional Scale in the Pacific Northwest

Coastal environments are dynamic and ever-changing, presenting a challenge for scientists, managers, and policymakers who seek to understand and mitigate the impact of these changes. Traditionally, the scarcity of shoreline position data has hindered efforts to comprehensively monitor coastal evolution, primarily due to the logistical challenges and expenses associated with data collection.

However, recent developments in satellite remote-sensing techniques have provided a game-changing solution. Researchers can harness these advancements to extract high-spatiotemporal-resolution data sets of coastal evolution from satellite imagery. This method offers a cost-effective and efficient means of monitoring coastal dynamics over different spatial and temporal scales.
 

In the study, a team of scientists from the Université de Toulouse, Oregon State University, Washington State Department of Ecology, and USGS focused on the mesotidal, high wave-energy, and dissipative sandy beaches of the Columbia River Littoral Cell (CRLC) in the Pacific Northwest. Their objective was to assess the accuracy of satellite-derived shoreline positions by comparing them to field observations.

The findings of the study, published in Cambridge Prisms: Coastal Futures, represent a significant breakthrough. By removing outliers and correcting satellite-derived waterline data for tides and wave runup, the researchers achieved a strong agreement between satellite-derived and field-observed shoreline positions along the CRLC. Notably, even the removal of outliers alone proved sufficient to extract accurate shoreline change trends.

The research highlights the transition from data scarcity to data abundance in coastal monitoring, made possible by advancements in satellite remote-sensing techniques. These data will provide invaluable insights into historical trends and patterns, empowering coastal communities, policymakers, and planners to devise proactive strategies for the prevention of—and adaptation to—potential future coastal hazards.