Royal - HKU Libraries - The University of Hong Kong

The Third Congress of the World MeteorologicalOrganisation adopted Celsius for measuring air temperatureand for general use in 1953.The Fourth Congress, in 1959, at which Hong Kong wasrepresented, noted that good progress had been made andresolved that Celsius be used in the international exchangeof air temperatures - a usage that became world-wide by1963.At the same time, some nations stopped using Farenheitfor any purpose, to avoid confusion.When he returned from the Congress, the Director of theObservatory, Dr. I. E. M. Watts, noted that the case forchanging to Celsius was even stronger in Hong Kong thanin Britain because:• Celsius had been used in China for many years andmany adult Chinese in Hong Kong were familiar with thescale.• Continental Europeans in Hong Kong had used Celsiusfor years.• Neighbouring countries, including China, Macau andJapan, used Celsius.• A large proportion of Hong Kong's population wasbelow school leaving age, a good age at which to introducea change.• Celsius was already used at the airport, the Observatory,and in schools and laboratories.• Given the rapid pace of technological development, achange should be made sooner rather than later.Several points of a more general nature which supportedthe need for a change were found, including:• Other countries were changing to Celsius.• The use of two scales was inefficient and undesirable.• Many more people in other parts of the world usedCelsius than Farenheit.• Major economic blocs, such as the European CommonMarket and the Communist countries, used Celsius exclusively.104