Big squeeze is on for tomato ketchup as planet warms up

TOMATO ketchup, a stalwart of British dinner tables, may become much rarer as climate change threatens to halve the fruit’s global harvest this century.

The sauce is made from the “processing tomatoes” variety, but the crops, like most worldwide, are at risk from rising temperatures.

A team led by Aarhus University in Denmark created a mathematical model to see how different climate change scenarios would affect production.

“There are two types of cultivated tomato: one for fresh consumption (like salads), usually grown under controlled environments; and one for industrial transformation known as processing tomatoes (like canned), usually grown under field conditions,” the researchers write in their paper, Nature Food.

“Processing tomatoes are important because they are used for tomato paste, tomato sauce, ketchup and other tomato-derived products.”

Around 180 million tons of tomatoes are grown every year, with two thirds produced by California, China and Italy.

Last year, the Intergovernmental Panel on Climate Change outlined five future global warming scenarios covering different levels of fossil fuel use and emissions.

By 2050, there would be a six per cent decline in tomato production, with little difference between the five potential futures. But between 2050 and 2100, there is a stark difference depending on the model and in the worst-case scenario, the harvest could be halved.