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Abstract This analysis quantifies the network dynamics, geographic concentration, and disparities in perishable food supply networks for temperature-controlled food shipments in the United States. The United States forms the core of global food systems and produces more high-quality data for network analysis than most other countries. We use the 2017 US Census Commodity Flow Survey and other publicly available data to derive empirical results from the Food Flow Model for perishable meats and perishable prepared foods. We identify the top ten counties for perishable food distribution and find that the Los Angeles and Chicago regions support the greatest volumes of perishable food movements. States that largely exist outside national perishable food networks are Arizona, Michigan, Montana, North Dakota, Texas, and West Virginia. Our analysis of US data highlights the importance of certain counties, states, and regions in perishable food networks and suggests areas where interventions could improve systems’ functions by increasing access to markets for farmers and access to food for underserved communities, especially those in rural regions. 

Coastal jetties are commonly used throughout the world to stabilize channels and improve navigation through inlets. These engineered structures form artificial boundaries to littoral cells by reducing wave-driven longshore sediment transport across inlet entrances. Consequently, beaches adjacent to engineered inlets are subject to large gradients in longshore transport rates and are highly sensitive to changes in wave climate. Here, we quantify annual beach and nearshore sediment volume changes over a 9-yr time period along 80 km of wave- dominated coastlines in the U.S. Pacific Northwest. Beach and nearshore monitoring during the study period (2014–2023) reveal spatially coherent, multi-annual patterns of erosion and deposition on opposing sides of two engineered inlets, indicating a regional reversal of longshore-transport direction. A numerical wave model coupled with a longshore transport predictor was calibrated and validated to explore the causes for the observed spatial and temporal patterns of erosion and deposition adjacent to the inlets. The model results indicate that subtle but important changes in wave direction on seasonal to multi-annual time scales were responsible for the reversal in the net longshore sediment transport direction and opposing patterns of morphology change. Changes in longshore transport direction coincided with a reversal in the Pacific Decadal Oscillation (PDO) climate index, suggesting large-scale, multi-decadal climate variability may influence patterns of waves and sediment dynamics at other sites throughout the Pacific basin.