The first-ever global analysis of the impacts of climate change on fruit and nut trees finds that an important determining factor for crop yields will be impacted, posing a risk of substantial economic losses for an industry worth an estimated US $93 billion annually.

An increasingly shortening “winter chill” period each year due to warming in many key growing regions is impacting agricultural production of fruits and nuts, according to a study published in the online journal PLoS ONE.

“Changes in winter seasons will change the ranges of many tree crops, and many growing regions may become unsuitable for some of our favorite fruits that are grown on trees," said Evan Girvetz, senior climate scientist at The Nature Conservancy and co-author of the report, “especially apples, cherries, and peaches.” The report also notes that other fruits and nuts such as apricots, walnuts, pistachios, plums and almonds will be affected by decreased “winter chills.”

The study, “Climate change affects winter chill for temperate fruit and nut trees,” was led by Eike Luedeling of the World Agroforestry Centre in Nairobi, Kenya. Co-authors include Girvetz of The Nature Conservancy, Patrick H. Brown of the University of California, Davis, and Mikhail A. Semenov of Rothamsted Research in Harpenden, United Kingdom.

Using observed daily weather for more than 4,000 weather stations around the world from the National Climatic Data Center of the U.S. and climate projections from three global climate models, the analysis estimates winter chill for two past years (1975 and 2000) and generates 18 future scenarios (at the middle and end of the 21st century) for the entire globe with The Nature Conservancy’s ClimateWizard tool. Results can be found at