Comparison of seasonal climate in China during the cold and warm phases of ENSO

Abstract

El Niño-Southern Oscillation (ENSO) events have serious impacts on weather patterns, agriculture and ecosystems, and play an important role in predicting regional and global climate. A 2-tailed Student’s t-test was used to analyze the differences of seasonal air temperature and rainfall between ENSO years (El Niño/La Niña years) and non-ENSO years in China, and the results indicate that summer temperature was lower, and winter, spring and autumn rainfall was higher in El Niño years, while in La Niña years, winter temperature was lower and summer rainfall was higher in China as a whole. There were significant regional differences in seasonal temperature and rainfall between ENSO and non-ENSO years. In El Niño years, summer temperatures in most regions of China were lower than those in non-ENSO years. Summer and autumn rainfall was higher in the mid-lower reaches of the Yangtze River but lower in North China, and winter rainfall was lower in southern China. In La Niña years, winter temperatures were lower in the mid-lower reaches of the Yangtze River and South China, and summer rainfall was higher in Northeast China, North China, the mid-lower reaches of the Yangtze River and Southwest China than those in non-ENSO years. We conclude that the impacts of ENSO on rainfall are more obvious than those on temperature, and the responses of seasonal temperature and rainfall to El Niño are more obvious than those to La Niña events in China.