The losses will grow to five billion dollars by 2020 and 14 billion by 2070, according to the joint study by the Brazilian Agricultural Research Center and the University of Campinas.

A team of 19 researchers evaluated the impact of rising temperatures on the cultivation of cotton, rice, black beans, coffee, sugar cane, sunflowers, cassava, corn and soybeans.

They found that higher temperatures and changes in rainfall patterns, along with an increase in storms, will cause these crops to migrate to places with a more hospitable climate.

Soybeans will be most affected by the climate change because they require consistent rain. The least affected will be sugar cane, which will gain ground as other crops shrink, the researchers said at a conference in Sao Paulo.

"This is what will happen if nothing is done," said Eduardo Delgado Assad, head of the research center. He proposed "massive investments in science and technology" to stop the crops from migrating to other geographic zones.

To slow global warming, he said, carbon emissions caused by deforestation must be reduced.

Silveira Pinto, a Campinas researcher, said the investment must be rapid to help the threatened crops adapt to climate change, a process that could take up to 10 years.

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