METEOROLOGICAL WARNINGS STUDY GROUP (METWSG)

Transcription

1 METWSG/4-SN No. 6 12/3/12 METEOROLOGICAL WARNINGS STUDY GROUP (METWSG) FOURTH MEETING Montréal, 15 to 18 May 2012 Agenda Item 6: Wind shear, turbulence and tsunami warnings TSUNAMI INFORMATION (Presented by Steve Albersheim, co-rapporteur of ad hoc group C) SUMMARY This paper presents a summary of the results of a survey of the present capabilities of the Asia/Pacific States to prepare and issue aerodrome warnings for Tsunami. This paper also discusses the international tsunami warning center system and framework. 1. INTRODUCTION 1.1 The third meeting of the Meteorological Warnings Study Group (METWSG/3) formulated the following Agreed Action 3/16: Agreed Action 3/16 Guidance on the issuance of tsunami warnings That an ad hoc group (C) consisting of Bill; Herbert, Juan, Jun, Ndiwa, Steve (co-rapporteur) and Shona (co-rapporteur) is to develop guidance on the provision of aerodrome warnings for tsunami and, in particular: a) examine existing capabilities of relevant countries to issue public tsunami warnings and the processes for States to forward them to meteorological service providers; (11 pages) METWSG.4.SN en.doc

2 METWSG/4-SN No b) determine the capabilities of meteorological service providers to extract tsunami information specifically relating to aerodromes (including land inundation) from public tsunami warnings; c) recommend how information on tsunami warnings can be included in an aerodrome warning; d) establish guidance material to support meteorological service providers on the issuance of aerodrome warning for tsunami; and e) produce a report by 15 January 2012 for consideration by the METWSG/4 Meeting. 1.2 A survey was prepared and undertaken by the Asia/Pacific Meteorological Advisories and Warnings Implementation Task Force (METWARN/I TF). A State letter and the survey were sent out on the 25th April 2011 (see the Appendix to this paper). 1.3 The results of this survey were first presented to the Fifteenth Meeting of the Communications/Navigation/Surveillance and Meteorology Sub-Group (CNS/MET SG/15) of the Asia/Pacific Air Navigation Planning and Implementation Regional Group (APANPIRG), as Working Paper Number 50 (WP50). 2. DISCUSSION 2.1 Survey of current capabilities Eighteen States in the APAC region responded to the survey. Some of the main results were: Most States have provisions to issue public Tsunami warnings. o One requires more training material and access to international experts. Need to improve on the compliance to the provision on issuing aerodrome warnings on Tsunami. o o A little more than half the States are not compliant for reasons such as authority (aerodromes not included in issuance authority). Two States have public Tsunami warnings issued directly to aerodromes and they consider this service meets their needs. States were aware of the source of Tsunami warnings. Sources varied from various national regional and international centers. Dissemination of public Tsunami warnings included phone, , fax, World Meteorological Organization (WMO) product over WMO circuit (over one-third), AFTN, SMS, and Internet.

3 - 3 - METWSG/4-SN No. 6 Criteria used for issuance of aerodrome warnings for a Tsunami varied. Five States issued the warnings based on the criteria from Tsunami warning centers. Three States relied on criteria determined by other government agencies (no details were provided). Three States monitor sensors directly and have criteria based on the location, magnitude and dept of the earthquake. The majority of States responded that their lead time requirements for an aerodrome warning on Tsunami were immediate or soon as practical. Respondents noted that there is a need to further evaluate the Tsunami emergency plans for aerodromes. Some States use public emergency plans that includes aerodromes and only a couple States have separate emergency planning for aerodromes for Tsunami Warnings. 2.2 Tsunami Warning Centers (TWC) CNS/MET SG/15 WP48 presented a complete overview of the international tsunami warning center (TWC) program for the Pacific Ocean. WP50 discussed the importance of maximizing the current capabilities of existing tsunami warnings systems and frameworks Pacific Tsunami Warning System (PTWS) Operations - One of the most important activities of the PTWS is to ensure the timely issuance of tsunami warnings to threatened coastal areas of the Pacific Ocean. When such an event occurs, the Centers provide timely and effective tsunami information and warnings for coastal communities in the Pacific to minimize the hazards of tsunamis, especially to human life and welfare International warning operations of the PTWS require the participation of many seismic, sea level, analysis, communication, and dissemination facilities operated by many nations throughout the Pacific Region. The Pacific Tsunami Warning Center (PTWC) serves as the operational center for the PTWS; sub-regional centers in Japan and Alaska work with PTWC to provide international warnings and advisories for the Pacific and its marginal seas. The international Tsunami Warning Centers (TWC) collect and evaluate data provided by participating countries, and issue appropriate bulletins to both participants and other nations, states or dependencies within or bordering the Pacific Ocean basin regarding the occurrence of a major earthquake and possible or confirmed tsunami generation Areas of Responsibility - The coastal areas of responsibility of the PTWC, West Coast and Alaska (WC/ATWC), and the Japanese Meteorological Agency/Northwest Pacific Tsunami Advisory Center (JMA/NWPTAC) are shown in figure 1 and 2. To ensure consistency and minimize confusion to customers, the TWC coordinate their earthquake parameters prior to official bulletin issuance for a common earthquake. Each TWC is authoritative for the earthquake parameters within a certain defined region near its own coastal area of responsibility The Joint Australian Tsunami Warning Centre (JATWC) is operated by the Bureau of Meteorology and Geoscience Australia. The JATWC has been established so that Australia has an independent capability to detect, monitor, verify and warn of the existence of tsunami in the Australian region and possible threats to Australian coastal locations and offshore islands.

4 METWSG/4-SN No Fig 1: JMA/NWPTAC areas of responsibility Fig 2: PTWC, WC/ATWC areas of responsibility OPERATIONAL PROCEDURES - Functioning of the system begins with the detection of an earthquake of sufficient size to trigger an alarm at the TWC. Generally, this will happen within a few minutes of the occurrence of any earthquake in the Pacific region with a magnitude above about 5.0. Duty personnel respond immediately and begin their analysis of the event. The TWC are staffed on a 24-hour a day, seven days a week basis to immediately respond. If a warning is issued, subsequent bulletins are issued, at least hourly, providing additional information and may continue,

5 - 5 - METWSG/4-SN No. 6 expand, or cancel the warning based on a combination of updated seismic parameters, sea level readings, numerical forecast model results, and historical data TSUNAMI BULLETINS - The TWCs issue several different types of messages, which contain the same information, but with slightly different formats or descriptive text. Significant coordination and agreed-upon rules of authority and procedures are in place between the international TWCs to ensure consistency in evaluation and reporting to their respective customers. The types of international messages are: Pacific-Wide Tsunami Warning Bulletin - A warning issued to all PTWS participants after there is confirmation of tsunami waves capable of causing destruction beyond the local area. Regional Expanding Tsunami Warning and Watch Bulletin - A message based initially on only seismic information that alerts all PTWS participants of the possibility of a widely destructive tsunami. Regional Fixed Tsunami Warning Bulletin - A message based initially on only seismic information that alerts all PTWS participants of the possibility of a regional tsunami. The area placed in Tsunami Warning status encompasses coastal regions within 1000 kilometers (km) of the earthquake epicenter. Tsunami Information Bulletin - A message issued to advise PTWS participants of the occurrence of a major earthquake in or near the Pacific, with an evaluation that there is either: o no widespread tsunami threat but the small possibility of a local tsunami, or o there is no tsunami threat at all TSUNAMI BULLETIN IDENTIFIERS- PTWC and WC/ATWC) tsunami bulletins are US National Weather Service products. The Northwest Pacific Tsunami Advisory Center (NWPTAC) bulletin is a Japanese Meteorological Agency (JMA) product. All products that are transmitted over the Global Telecommunications System (GTS) are described by WMO headers. The standard products have the headers: WEPA40 and WEPA 42 (PTWC, PHEB station originating code) WEPA40 (NWPTAC, RJTD station originating code), or WEPA41, WEPA43, and SEAK71 SEUS71 (WC/ATWC, PAAQ station originating code) The WC/ATWC also issues Pacific public-friendly messages under WEAK51 and WEAK MESSAGES - Bulletins issued by TWCs are guidance or advisory for national and local authorities. The authoritative tsunami warning agency for each country, territory, or administrative area is designated by its national government or administrative head. This agency has the fundamental responsibility for public safety in a tsunami emergency. The authority for issuing tsunami warning instructions to the public resides with this agency and not with the international TWC. It is recommended that only a single agency should be designated to ensure a single authoritative voice within an area. A national agency is usually designated as the 24-hour a day, seven days a week PTWS Tsunami Warning Focal Point (TWFP) for receiving official tsunami information from the international tsunami warning centers DISSEMINATION COMMUNICATION METHODS- To ensure the timely and effective dissemination of tsunami warnings and information, communication methods capable of rapidly reaching all PTWS participants are essential. Since such traffic is relatively infrequent, existing communication channels are used instead of establishing a separate communication system. These include the Global Telecommunications System (GTS) of WMO, Aeronautical Fixed Telecommunications System (AFTN) of the International Civil Aviation Organization (ICAO), and other more common systems such as facsimile transmission over telephone circuits, and internet and web postings.

6 METWSG/4-SN No Facsimile and internet are not transmitted through dedicated communications channels, and as such cannot be guaranteed for timely delivery. These common methods should be used as a secondary and/or backup means of communications by TWC. The GTS and AFTN are dedicated communication circuits Maintained by States for WMO and ICAO respectively to support the transmission of bulletins in a timely manner. Thus, while all dissemination methods are made simultaneously by the issuing centers, bulletins may reach their destinations at different times, depending on the communication method used. 3. RECOMMENDATION 3.1 Action 3/16 c) and d) asked the ad hoc group C to recommend how information on tsunami warnings can be included in aerodrome warnings; and establish guidance material to support meteorological service providers on the issuance of aerodrome warnings for tsunami. As is evident based on the survey and the assessment, the provision of tsunami warnings is complex and States have different protocols. Introducing another level of providing a warning would mostly likely compound the problem and delay the provision of the information in that a tsunami warning is very time critical where the time of notification can be less than an hour in some geographical areas. 3.2 The ad hoc group C, after examining the implementation of the provision of tsunami information, proposes that there may be another option on how best to disseminate this information in a timely manner, by providing information directly to the aerodrome from the TWC. This provision would be an alternative for States to choose. If a State chooses to use the international tsunami warning center, it is then the responsibility of that State to work with the international tsunami warning center to make arrangements so that warning and information products reach the intended aerodrome and appropriate aerodrome officials and users (e.g., airlines) in the most timely manner. 3.3 The group is invited to adopt the following draft actions: Draft Action Agreed 4/xx Provision of tsunami information for an aerodrome That instead of adding tsunami to the criteria for an aerodrome warning, that to provide the information to the aerodrome in the most timely manner, information regarding a tsunami be provided directly from: a) the National body responsible for the dissemination of Tsunami warnings and information; or b) for States without such a National body, International Tsunami warning center who area of responsibility include that State. That the States which choose b), the State work with the appropriate international tsunami warning center to make arrangements such that tsunami warnings and information products reach the intended aerodrome and appropriate aerodrome officials and users (e.g., airlines) in the most timely manner.

7 - 7 - METWSG/4-SN No ACTION BY THE GROUP 4.1 The group is invited to: a) note the information in this paper; and. b) consider the recommendation provided.

8 (12 pages) METWSG.4.SN en.doc APPENDIX

9 METWSG/4-SN No. 6 A-2

10 A-3 METWSG/4-SN No. 6

11 METWSG/4-SN No. 6 A-4 END