(Photo: The HKO staff launching a pilot balloon at the Tsim Sha Tsui Headquarters in the 1930s. (Courtesy of the family of Mr Heywood, former Director of the HKO))
The upper air observing station of the Hong Kong Observatory (HKO) was accredited as a centennial observing station by WMO in June. It is the first upper air observing station to be accredited since the
introduction of the recognition mechanism.
HKO commenced upper air meteorological observations in 1921. In the early days, the work was carried out at its headquarters in Tsim Sha Tsui and pilot balloons were used to measure upper air wind direction and speed. In 1949, HKO started using radiosondes and extended the measurements to include air temperature, humidity and pressure. In 1951, upper air observations moved to the nearby King’s Park Meteorological Station as the headquarters was being surrounded by buildings. Over the years, the HKO made continuous improvement in the technology for upper air observations, extending the measurements to include upper air radiation level and ozone content. In 2004, an Automatic Upper Air Sounding System was installed, the first of its kind in Southeast Asia. In 2020, HKO started the measurement of upper air water vapour content using balloons with frostpoint hygrometer.
In 2017, the surface observing station at HKO Headquarters was accredited by WMO – one in a batch of first centennial observing stations to be recognized when the mechanism was introduced. So far, WMO has accredited about 300 observing stations with 100 years or more of observational history. The full list is available here.
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