According to Mr. Sai-tick Chan, Assistant Director of the Hong Kong Observatory (HKO),Early Warning System in Hong Kong consists of 4 pillars. The first is “Disaster risk knowledge” which is about the systematic collection of data of risk assessments. The second is about “Detection, Observations, Monitoring, Analysis and Forecasting of Hazards”. The third is about “Warning dissemination and communication” which involves the use of various channels for communicating risks information and early warnings. The fourth is about “Preparedness and response capabilities” at the local government level for responding to warnings.

Disaster risk knowledge

To set up the early warnings system, a comprehensive understanding of disaster risk is essential. Tropical Cyclone Impact Data from Regular Sources can be found on HKO website.

With the spread of smart phones and the mobile Internet, the public can become a node in a vast network of weather observation with the help of smart phones. HKO is committed to promoting societal impact information collection from Crowd-Sourcing, encouraging the public to participate in meteorological observation, and providing more diverse and extensive meteorological information and data.

Moreover, the public can report and share weather information by the mobile App MyObservatory, which was launched by HKO. The “My Weather Observation” function allows the public to report weather phenomena. Some high-impact weather phenomena like hail and tornado will only be displayed after verification of information from users.

Members of the Community Weather Observation Scheme (CWOS) Facebook group can share weather photos and video clips to CWOS Facebook group through this function.

Detection, observations, monitoring, analysis and forecasting of hazards

The Hong Kong Meteorological observation Network comprises over 150 automatic weather stations. HKO operates a range of weather monitoring equipment, including a territory-wide network of automatic weather stations for measuring wind, pressure, temperature, humidity and rainfall. There also have microclimate stations, wind measurement on pilot boats and fishing vessel, and Automatic Weather Station and Raingauge network.

HKO has developed a suite of nowcasting systems, including the "Short-range Warning of Intense Rainstorms in Localized Systems" (SWIRLS), to aid rainstorm warning operation as well as high-impact weather forecasting for the public and the aviation community.

Warning dissemination and communication

When inclement weather is expected several days ahead, reminders in form of Weather Note will be issued to remind the public to pay attention to weather changes ahead and take precautionary measures.

The column serves as an effective means to communicate with the public on possible high-impact hazards and extreme weather and the associated uncertainties.

HKO makes use of all available dissemination channels to deliver weather forecast and warnings. The “My Weather Observation” function in MyObservatory mobile App allow users to select personalised locations, and can provide weather forecasts for the coming 3 days at hourly intervals presented in graphical form.

Cumulative downloads of MyObservatory Mobile App are over 9.7 million as of February2023.

Preparedness & Response

HKO organizes Pre-Typhoon Season meetings every year, and provides tropical cyclone Outlook Briefings fortnightly to clarify potential typhoon impacts. HKO also conducts annual exercises to test the emergency response capabilities of different areas.

At the same time, HKO has intensified publicity efforts by conducting school talks and public seminars on climate and setting up the "Friends of the Observatory" to enhance communication between the public and HKO, and carry out "Science in the public Service" campaign.

Editor: Luo Lan