Implementation of CAP in Hong Kong Observatory TONG Yu-fai Scientific Officer Hong Kong Observatory Hong Kong, China Common Alerting Protocol (CAP) Implementation Workshop WMO Headquarters, Geneva, Switzerland, 23 – 24 April 2013

Hong Kong Observatory (HKO) A government department of Hong Kong Responsible for forecasting weather and issuing warnings on weather-related hazards in HK Monitor and assess radiation levels in HK, and provide geophysical services

Weather Warnings in Hong Kong Hong Kong Observatory (HKO) is the alerting authority in Hong Kong to issue the following weather warnings: Special Announcement on Flooding Tropical Cyclone Warning Signals (number-coded) Landslip warning Strong Monsoon Signal Fire Danger Warning Rainstorm Warning Signals (colour-coded) Very Hot Weather Warning Cold Weather Warning Thunderstorm Warning Frost Warning

Dissemination of Weather Warnings Internet Website http://www.weather.gov.hk http://www.hko.gov.hk eXtensible Markup Language (XML) Mobile applications Telephone enquiry system Public Mass media (newspaper, radio and television) Social Network Twitter/Weibo SMS Delivery via diverse and multiple means to communicate weather information of different volumes and degrees of details

Delivery of Warning Messages in XML format Currently, HKO disseminates weather warning messages in its own XML-based format to users with the needs of system automation, facilitating exchange of weather warnings between machines. Common Alerting Protocol (CAP) is a XML-based data format for exchanging warning messages. Why do HKO need to deliver weather warnings in CAP - another XML-based format?

HKO’s XML data service Provision of weather bulletins (including warnings ) in XML since 2003 A website was set up to allow users to retrieve the XML bulletins over the Internet

HKO’s XML data service Wide spectrum of users Weather Info in XML Media Transport operators Utilities Telecom Service Industry Government users Wide spectrum of users Effective means to deliver up-to-the-minute weather reports/forecasts and warning electronically

Limitations of the HKO’s XML Service for Delivery of Weather Warnings “Proprietary” XML Schema The schema specifying the HKO’s XML bulletins is proprietary, not adopted from any open data standard No open library support. Users have to develop their tools to retrieve the HKO’s XML bulletins and ingest them into their systems. Could not contain reference to additional information in the form of a digital asset No geographic information. Messages target to all people in HK even though the incident affects only a specific area.

Limitations of the HKO’s XML Service for Delivery of Weather Warnings Multiple message on same incident For certain weather warnings, multiple XML bulletins referring to the same incident are issued to users, but containing different aspects of the information about the incident. TC bulletin (TC analysis info) TC signal bulletin (which TC signal is issued?) TC warning announcement (event description & actions to be taken) Tropical Cyclone Warning Signal Multiple messages for same event may cause user confusion and incur extra effort on users to incorporate the XML bulletins into their information systems.

Why do HKO need to deliver weather warnings in CAP? CAP is an XML-based data format for exchanging public warnings. It has advantages over the HKO’s XML data service: CAP data format HKO’s XML data format Open data standard for exchanging public warnings   Geographic information of target area Reference to additional information (e.g. image/audio files)

Implementation of CAP for Local Weather Warnings Combine messages of same event into a single CAP message Example: TC warning signal TC analysis & forecast track information TC warning bulletin (which TC signal is issued?) TC warning announcement (event description & actions to be taken) These messages are originally coded in 3 different XML bulletins CAP Combine them into a signal CAP message Tropical Cyclone Warning Signal

Implementation of CAP for Local Weather Warnings Combine messages of same event into a single CAP message Example: TC warning signal CAP message for TC warning TC warning bulletin (which TC signal is issued?) <headline>TC No. 3 is issued at XX:XX HKT</headline> TC warning announcement (event description & actions to be taken) <description>…</description> <instruction>…</instruction> <parameter> [analysis/forecast positions & intensities] </parameter> TC analysis & forecast track information

Challenge of Applying CAP for Weather Warnings in HK Certain CAP elements could not be directly determined by HKO’s warning messages CAP element Values allowed by CAP Warnings issued by HKO Urgency Immediate, Expected, Future, Past, Unknown Either Immediate or Expected Severity Extreme, Severe, Moderate, Minor, Unknown Rainstorms: Amber/Red/Black TC warning: Number-coded system Fire danger warning: Yellow/Red Certainty Observed, Likely, Possible, Unlikely, Unknown Either Observed or Likely

Option 1 Develop rules to assign values of CAP <severity> for each type of weather warnings. Rainstorm Warning Signals 30 mm/hr 50 mm/hr 70 mm/hr CAP <severity>: Extreme, Severe, Moderate, Minor ? As HK people already get used of the number- and colour-coded warning systems, the selection of CAP <severity> values must match their perception on the severity of local weather warnings. The warning types (e.g. amber/red/black for rainstorms ) will be coded in the <eventCode> element.

Option 2 Extend the value domain of the CAP <severity> element to include the HKO’s number- & colour-coded warning systems However, it would NOT conform to the XML Schema of CAP!

Tropical Cyclone Warning for Shipping by Hong Kong Observatory Tropical cyclone over the South China Sea could pose a threat to mariners and ships at sea over the region HKO issues TC warning to ships when a tropical cyclone is located with the area 10o to 30o N and 105o to 125o E HK Target users: mariners/ships over the warning area TC Warning Area of Hong Kong

Tropical Cyclone Warning for Shipping by Hong Kong Observatory Contain information about TC analysis and position/intensity forecast up to 72-hour ahead Update every 3 hours Broadcast to ships via NAVTEX (a radio frequency broadcast system, receiving by means of direct-printing telegraphy)

TC Shipping Warning: Event focusing Affected Area T+48 hrs T+24 hrs T+0 TC warning for shipping are focusing on the event, moving from one place to another For TC shipping warning, defining an area for sending alert is not as straight-forward as other warnings

Issues need to be rectified in adopting CAP for TC shipping warning Define what kind of alert to be delivered for the CAP message of the TC shipping warning. Decide how to determine the alert area of the CAP message to better meet the needs of the recipients. Decide whether and how to break message into individual CAP alerts for different areas that will be affected at different forecast periods, e.g. 0<T<=24; 24<T<=48, etc. Design rules for assigning values to elements urgency, severity and certainty Decide on how forecast track could be encoded and in what format

Provide alert / notification for the presence of TC of a particular strength Break the TC shipping warning into different time intervals, e.g. 0-24, 24-48, 48-72, etc. Alert area would be the polygon bounding the initial and final positions of the TC including the uncertainty circles Provide alerts for the strongest intensity Forecast track could be encoded in other XML format, e.g. CXML, KML, etc. and attach to the CAP in the <resource> element

Provide alert / notification for the presence of TC of a particular strength Area B Area A T+48 hrs T+24 hrs T+0 CAP (0<T<=24) Urgency: Immediate Target Area: A CAP (24<T<=48) Urgency: Expected Target Area: B

Next Steps … Develop rules and automatic system to convert all local warnings & TC advisories into CAP format Set up a dedicate website to publish the CAP warnings and feeds Develop public outreach and promulgate users (media, public utilities, transport operators, etc) to make use of CAP in their information systems

Thank You