Analysis of the Characteristics of 60 Years of Degree-Day Measurements in Guangzhou Based on Apparent Temperature

HU Lin; GAO Xiao-rong; JIA Ning-yuan; XU Ze-ming

doi:10.3969/j.issn.1007-6190.2023.06.010

Abstract：Based on the long time series of air temperature,relative humidity and wind speed data for a national meteorological observation station in Guangzhou from 1961 to 2020,this work proposes a new algo-rithm for determining degree-day measurements based on apparent temperature(tg)and analyzes their varia-tions.The temperature-day measurement is defined as the deviation of daily mean temperature from a preset base temperature.The results are shown as follows.For the area of Guangzhou,heating degree-day(HDD)occurs mainly from November to the following March,which decreases significantly over the years at an aver-age rate of 2.06 d every ten years,and cooling degree-day(CDD)happens mainly from April to October,which tends to increase over the years at a rate of 2.02 d every ten years.Further analysis of this apparent temperature based measurement for Guangzhou shows that its multi-year mean of HDD is 308.4 ℃·d,much lower that of Chongqing(1 138.8 ℃·d)and Beijing(2 922.6 ℃·d),and its multi-year mean of CDD is 385.2 ℃·d,much higher than that of east China(about 160 ℃·d).It suggests that it needs more energy to cool via air conditioning from the prime summer to autumn in Guangzhou.As the apparent temperature based numbers of HDD and CDD days are larger than those based on daily mean temperature and the difference in CDD is much more significant,it is then suggested that as far as summertime cooling in the metropolitan is concerned,more attention should be paid to the discomfort brought about to the human body due to damp and sultry heat as well as windless conditions,and the apparent temperature based degree-day measurement is more suitable to deal with energy adaptability in areas where the winter is relatively warm and the summer is relatively hot.