Temperature trends in Hong Kong from a seasonal perspective

Abstract

We examined the seasonal trends of mean and extreme temperatures in Hong Kong using data from 1885-2010. The analysis revealed that the daily maximum temperature (TMax), daily mean temperature (TMean), and daily minimum temperature (TMin) of Hong Kong had a significant long-term increasing trend in all 4 seasons and that the warming trend was more prominent in winter and spring. The relatively higher rate of increase in temperatures in winter and spring could be attributed to local urbanization effects and the weakening of the East Asian winter monsoon in the last few decades. For extreme indices, we observed a significant increase in the hot indices (TN90p and TX90p) and a significant decrease in the cold indices (TX10p and TN10p) in all seasons. The seasonal variations in the heating and cooling degree-days (HDD and CDD) also indicated that CDD in spring, summer, and autumn had a significant increasing trend, while HDD in spring, autumn and winter had a decreasing trend. Analysis of the hot and cool periods in Hong Kong showed a significant decreasing (increasing) trend in the number of cool (hot) days. Also, the cool (hot) period has become shorter (longer) over the last century. © Inter-Research 2012.