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Abstract The food system is an important contributor to carbon dioxide (CO 2 ) emissions. The refrigerated food supply chain is an energy-intensive, nutritious and high-value part of the food system, making it particularly important to consider. In this study, we develop a novel model of cold chain food flows between counties in the United States. Specifically, we estimate truck transport via roadways of meat and prepared foodstuffs for the year 2017. We use the roadway travel distance in our model framework rather than the haversine distance between two locations to improve the estimate for long-haul freight with a temperature-controlled system. This enables us to more accurately calculate the truck fuel consumption and CO 2 emissions related to cold chain food transport. We find that the cold chain transport of meat emitted 8.4 × 10 6 t CO 2 yr −1 and that of prepared foodstuffs emitted 14.5 × 10 6 t CO 2 yr −1 , which is in line with other studies. Meat has a longer average refrigerated transport distance, resulting in higher transport CO 2 emissions per kg than processed foodstuffs. We also find that CO 2 emissions from cold chain food transport are not projected to significantly increase under the temperatures projected to occur with climate change in 2045. These county-level cold chain food flows could be used to inform infrastructure investment, supply chain decision-making and environmental footprint studies.
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Overview of cold chain development in China and methods of studying its environmental impacts
Abstract The cold chain (refrigerated supply chain) is an important application of refrigeration technologies. The capacity of the cold chain industry is growing rapidly in emerging economies such as China, leading to significant environmental impacts, especially greenhouse gas (GHG) emissions. By conducting the literature review, this study begins with presenting a comprehensive overview of the cold chain industry in China. We observed that China has a large total cold warehouse capacity but low capacity per capita. Then, we directly link the example of the cold chain in China to the methods of evaluating the GHG emissions from the cold chain industry. It is observed that existing studies either primarily focus on the lifecycle of food with less consideration on the cold chain facilities or primarily focus on the lifetime of a certain stage of the cold chain (e.g., refrigerated transportation) with less consideration on food. Neither frameworks capture the entire cold chain system. Moreover, we argue that existing studies lack investigations of the cold chain GHG emissions on the national scale. To evaluate the overall GHG emissions, we recommended that one can use the bottom-up approach. First, use the lifecycle assessment (LCA) to estimate the single-unit level (e.g., one kg food, one particular refrigerated warehouse) cold chain emissions. Second, aggregate up to the national scale by the distribution patterns of the cold chain networks. Finally, we identify the crucial future issues regarding collecting cold chain lifecycle inventory data, investigating the cold chain network and the overall environmental impacts in China, regulation and technology needs for expanding the clean refrigeration technologies, and the implications of the cold chain development to water, land, and society.
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- Award ID(s):
- 1804287
- PAR ID:
- 10209114
- Publisher / Repository:
- IOP Publishing
- Date Published:
- Journal Name:
- Environmental Research Communications
- Volume:
- 2
- Issue:
- 12
- ISSN:
- 2515-7620
- Page Range / eLocation ID:
- Article No. 122002
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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