LetterEarth SciencesModulation of the urban heat island by the tourism during the Chinese New Year holiday: a case study in Sanya City, Hainan Province of China

The urban heat island (UHI) represents one of the most significant human impacts on the earth system. In recent decades, the number of the tourists has a remarkable increase in China and also other regions of the globe. However, it is still unclear whether or to what extent the tourism can affect the UHI. Here, we investigate the role of the tourism for the UHI during the Chinese New Year (CNY) holiday based on a case study in tropical Sanya City, which attracts many tourists for celebrating the CNY and enjoying the warm climate during the holiday. We find that the UHI effects expressed as daily mean (ΔTmean), maximum (ΔTmax), and minimum (ΔTmin) surface air temperature differences between urban and nearby non-urban stations averaged over the period of 1995-2004 during the CNY week were 0.48°C (39%), 0.66°C (61%), and 0.42°C (26%) higher than those averaged over the background period (8 weeks including 4 weeks before and 4 weeks after the CNY week), respectively. These changes are all significant at the 99% confidence level. Our findings highlight previously unidentified impact of the tourism on the UHI based on a case study in Sanya City, Hainan Province of China.