The Impact of Atmospheric Intraseasonal Oscillation on High-Temperature Weather in Eastern Guangdong from May to June
LIU Yongtao
WEN Junxian
XIE Jiehong
LIN Weibin
WANG Jieyu
LIU Zhiqing
Abstract：To understand the characteristics and formation mechanisms of high temperatures in eastern Guangdong,this study utilized daily maximum temperature data from 20 national meteorological stations in eastern Guangdong from May to June between 1981 and 2022,along with the Boreal Summer Intraseasonal Oscillation(BSISO)index from APCC,and reanalysis data from NCEP and NOAA.Methods such as linear regression,trend analysis,power spectrum analysis,ButterWorth bandpass filtering,and chi-square tests were employed to analyze the climatic characteristics of high temperatures in eastern Guangdong from May to June and the influence of BSISO.The results are shown as follows.Over the past 42 years,the frequency of high temperatures in eastern Guangdong from May to June has increased significantly,with the coastal areas in the east and south experiencing slightly higher rates of increase compared to the inland northern regions.High temperatures in eastern Guangdong exhibit clear intraseasonal oscillation signals.The probability of high temperatures increases when BSISO1 is in phases 2-4 or BSISO2 is in phase 1.One of the reasons for high temperatures in eastern Guangdong is the enhanced geopotential height over the region,leading to in-creased adiabatic heating.Additionally,clear skies and reduced rainfall promote increased diabatic heating,which also affects the temperature structure and weather conditions in eastern Guangdong.
Keywords：climatologyhigh temperaturerelative thresholdBoreal Summer Intraseasonal Oscilla-tionMay-Juneeastern Guangdong
Publication Date：2025-04-20
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：6( 6-11 )