Western Australia
December 4, 2025

New research has revealed rising temperatures and traffic congestion cause minimal losses in California’s processing tomato industry, which offers important insights for Australia’s agricultural supply chains.

The research, published in the  American Journal of Agricultural Economics, analysed 1.4 million truckloads of tomatoes transported from thousands of farm fields to processing facilities between 2011 and 2020. 

Dr Sarah Whitnall, from The University of Western Australia’s School of Agriculture and Environment, conducted the analysis during her postdoctoral research at the University of California, in Davis, US.

“Results highlighted how highly coordinated and efficient supply chains can buffer agricultural industries from climate impacts,” Dr Whitnall said.

“It is rare to find a case where climate change has only a negligible effect but the supply chain is a well-oiled machine and losses are relatively small, and  while temperature does increase loss, it’s not by a huge amount.”

Truckload was linked to hourly temperature and traffic records, and it found losses were lowest when cool temperatures coincided with slower traffic.

The highest losses occurred when heat combined with congestion and even then, the share of damaged tomatoes rose only from around one to two per cent.

Dr Whitnall said the findings are particularly relevant for Australia, where agricultural supply chains often span long distances and face increasing heat stress.

“Although this case study is from California, the lesson for Australia is clear — efficiency is a powerful form of climate adaptation,” she said. 

“Coordination along our supply chains reduces food loss and builds resilience as temperatures rise.”

She said similar research could help industries such as horticulture and viticulture to better understand and respond to climate pressures across transport and logistics networks.

The research was supported by the US Department of Agriculture’s Agriculture and Food Research Initiative.

REFERENCE

Postharvest losses from temperature during transit: Evidence from a million truckloads
American Journal of Agricultural Economics
 

Website: http://www.uwa.edu.au

Published: December 4, 2025