A once-a-century drought has lowered the water level of Argentina's main grains transport river, reducing farm exports and boosting logistics costs in a trend that meteorologists said will likely continue into next year.

The South American grains powerhouse is the world's No. 3 corn supplier and No. 1 exporter of soymeal livestock feed, used to fatten hogs and poultry from Europe to Southeast Asia. Farm exports are Argentina's main source of hard currency needed to bolster central bank reserves sapped by a three-year recession.

Southern Brazil, source of the Parana River, has been hit by severe dryness for three years. This has reduced water levels in the Argentine ports hub of Rosario, Santa Fe province, where about 80% of the country's agricultural exports are loaded.
"This is about a once-in-a-hundred-years event. That's the type of frequency we are looking at," said Isaac Hankes, a weather analyst at Refinitiv, financial and risk business of Thomson Reuters.

On Monday the United Nations climate panel's report found that climate change is making extreme weather events more common. One meteorologist told Reuters the situation could "even get worse after the rainy season" set to start in late September.

Ships sailing from Rosario are loading 18% to 25% less cargo than normal due to the shallow water, said Guillermo Wade, manager of Argentina's Chamber of Port and Maritime Activities.