In 2019, 15 US retail companies emitted 12.7 million metric tonnes of carbon dioxide (CO2) emissions, equivalent to 1.5 million US homes, by importing the majority of their goods on fossil fuel-powered ships, concludes a report from environmental organisations and Pacific Environment.

The CMA CGM Marco Polo passes under the Verrazzano-Narrows Bridge in New York, May 2021. (Photo by Timothy A. Clary/AFP via Getty Images).

Retail giants – including Walmart, Amazon and Ikea – should reduce maritime emissions by ensuring contracts with shippers require all products to travel on the cleanest ships. They should also commit to 100% zero-emission maritime supply chains by 2030, the report says.

Walmart’s sea transport produced 3.7 million metric tonnes of CO2 in 2019, equivalent to a US coal-fired power plant burning for an entire year. Ashley Furniture’s maritime emissions were 2.2 million metric tonnes of CO2, while clothing retailer Target produced two million metric tonnes, more than the world’s 20 smallest countries combined, the report says.

To achieve a zero-emission shipping industry by 2030, the report calls for US policymakers to mandate climate and air emissions reductions for all ships that dock in US ports. They also want to see improved transparency in maritime emissions data via a mandated domestic monitoring, reporting and verification system.