Global warming has in recent years boosted sales of iced drinks in fall and winter as well as raised the prices of imported fruits in Korea.
Temperatures have been steadily increasing here, standing at 12.8 degrees Celsius on average between 2001 and 2010, making this the hottest decade since comprehensive statistics were first compiled in 1973, according to the National Institute of Meteorological Research.
The country also saw the highest level of precipitation over the same period, or 1,395 mm on average.
As the Korean Peninsula gradually becomes more subtropical in climate, with each passing year higher temperatures and more rain, this September is proving to be both hotter and wetter than in previous years, it added.
The changing weather patterns have caused sales of iced beverages to shoot up even long after the summer ends.
According to Smoothie King, which specializes in fruit drinks mixed with ice, its sales jumped 33.6 percent from September to November, compared to the same period in 2010. And from December 2011 to this February, they rose 25.3 percent on-year.
The increases were even larger than the 18.5 percent rise from summer 2010 to 2011, calculated as the months of June through August.
"As the mercury has climbed in both summer and winter, more people are turning to refreshing smoothies regardless of the season," said Yoo Sun-hwa, Smoothie King's marketing manager.
CJ Foodville's coffee chain A Twosome Place saw a 55-percent increase in sales of iced beverages from November through December last year, it said.
SPC's café chain Pascucci sold 85 percent more iced Americanos and 30 percent more iced caffe lattes last November on-year. Sales of its regular Americanos and caffe lattes dropped by 5 percent, while overall demand for its hot drinks fell by 9 percent, it said.