Professor Wyss Yim's letter published on January 29 ("Hottest year? Not in Hong Kong") argued that urbanisation is the culprit of all the warming that is observed, and that the global temperature actually decreased during the period from 1998 to 2014.
This is typical of climate sceptics who often cherry-pick data to argue that the globe is not warming.
If urbanisation were the only reason for the observed warming, why has the Arctic sea ice shrunk by about a third since 1980? Why have significant amounts of ice melted in many of the glaciers? Why has the ocean temperature continued to increase? In these places, very few people live, and surely no urbanisation exists.
Yes, urbanisation enhances warming in the cities but the increase in temperature is global and not confined to the cities. According to the World Meteorological Organisation, the weather authority within the United Nations, the average temperature over land and ocean in 2014 was 0.57 degrees Celsius above the 1961-1990 average.
Note that the average over land includes all temperature records and not only those in the cities. Just because the temperature in Hong Kong is not the hottest does not imply global warming is not occurring!
As to the "pause" in the warming, the climate system is very complex and the global temperature will always be affected by many factors that occur on relatively short time scales.
