Climate change batters U.S. cereals — but boosts American avocados


Climate change is shifting the patterns of which foods can be cultivated in which regions, driving fluctuations in prices and output across the agricultural spectrum, according to a series of recent studies.

For the United States, these shifts are driving up the price of growing cereal grains - but potentially making it possible to grow tropical crops like coffee and avocados in areas with traditionally temperate climates.

Rising global temperatures have driven farmers' crop insurance payouts up dramatically since 1995, according to a study by the Environmental Working Group (EWG). That has meant a fourfold increase due to drought and a threefold increase due to flooding, the EWG reported.

"The climate crisis is already pummeling American farmers, at taxpayers' expense," because the federal crop insurance plan is heavily subsidized, EWG Midwest Director Anne Schechinger said.

Taxpayers paid $103.5 billion in subsidies for crop insurance premiums between 1995 and 2020, according to the EWG. That money doesn't currently come with any climate strings attached, and the Department of Agriculture often pays farmers "for the same type of losses, year after year," the EWG report found.

These losses are geographically concentrated: losses due to rain have been highest in 10 counties in the Dakotas, and losses due to drought were highest in 10 Texas counties, the report found.

These destructive weather extremes are only expected to grow, and crop ranges will change alongside them, according a NASA study published last November in the journal Nature.

Changes in temperature, ground-level carbon dioxide and rainfall patterns could drop corn yields by up to 24 percent - but raise wheat yields by 17 percent, with smaller declines in soy beans and rice, the study found.

"While future yield estimates remain uncertain, these results suggest that major breadbasket regions will face distinct [human-caused] climatic risks sooner than previously anticipated," the NASA study found.

These impacts to major cereal-growing regions will come alongside steep declines in many regions for harvests of cashews, arabica coffee and avocados - all key cash crops for small farmers in tropical countries, according to a University of Zurich study released Wednesday in the public research journal PLOS ONE.

Experts have long known that climate change would harm farmers' ability to grow arabica coffee - the most commonly cultivated species - in "most regions where it is currently grown," the PLOS study noted.

But there had been no studies of the impacts on avocados and cashews - or on the impacts on coffee itself of changing land and soil conditions, which may alter "pH, texture and slope" due to climate-linked factors like erosion or carbon dioxide concentration in the air, according to the study.

When these factors are accounted for, the researchers found "declines in suitability" for growing coffee in "all major producing regions," including Southeast Asia and the northern half of South America.

The researchers also predicted more limited declines in key cashew-producing regions like India and West Africa, and avocado-growing regions like the Caribbean, Andes and Southeast Asia.

For more temperate countries, however - like the United States, China, and East African nations like Kenya or Tanzania - the Swiss researchers identified a bright spot: expanding zones of "future suitability," particularly for avocados and cashews, at higher elevations or locations further from the equator.

"For both cashew and avocado, areas suitable for cultivation are expected to expand globally while in most main producing countries, the areas of highest suitability may decrease," the researchers found.