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U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration NATIONAL WEATHER SERVICE
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TO: All Holders of Operations Manual
SUBJECT: Transmittal Memorandum for Operations Manual Issuance 96-2
1. Material Transmitted:
WSOM Chapter F-61, Earthquake Reports.
2. Summary:
This chapter has been issued to show revised procedures for actions to be followed by NWS Forecast Offices in the event of an earthquake.
3. Effect on Other Instructions:
Supersedes entire Chapter F-61, WSOM Issuance 84-2, dated February 13, 1984.
Elbert W. Friday, Jr.
Assistant Administrator
for Weather Services
Issue Date Org. Code NATIONAL WEATHER SERVICE Part Chap.
3-6-96 W/OM12 Operations Manual F 61
EARTHQUAKE REPORTS
Table of Contents:
1. Purpose
1.1 Definitions
2. Earthquake Reporting Program
2.1 Scope
2.2 Reporting Procedures
2.2.1 Contiguous United States and Puerto Rico
2.2.1.1 Earthquake Report Format
2.2.2 Alaska and Hawaii
2.3 Request for Reports
2.4 NEIC Earthquake Products
2.5 Customer Outreach
Exhibits:
F-61-1 Modified Mercalli Intensity (Damage) Scale of 1931
F-61-2 Product Identifiers and Dissemination AFOS, NWWS, NWR
F-61-3 Telephone List - NEIC
F-61-4 Example Earthquake Reports
F-61-5 Earthquake Questionnaire
1. Purpose. This chapter promulgates the National Weather Service's (NWS) procedures for the dissemination of information in the event of an earthquake and provides for cooperation with the United States Geological Survey (USGS) in reporting earthquake information to the National Earthquake Information Center (NEIC).
1.1 Definitions. AFOS: Automation of Field Operations and Services. AFOS is an internal NWS communications network and field office computer system for data and product display, message composition, and message distribution. AFOS is used in the continental United States. AFOS will be phased out with the Modernization of the NWS. Earthquake Data: Specific data and computed information about an earthquake, such as phase arrival times and amplitudes, hypocentral locations in geographic coordinates, magnitudes, etc. Earthquake Magnitude: A measure of the size of an earthquake, obtained by measuring the amplitude of seismic waves on seismographs. The earthquake magnitude is related to the amount of energy released at the source of the earthquake. The first instrumental earthquake-magnitude scale was invented by Dr. Charles F. Richter.
Macroseismic Information: Information on earthquake effects that are observed without the aid of seismic instruments, such as where the earthquake was felt, how strongly the earthquake was felt (e.g., weakly, moderately, strongly), how many people felt the earthquake (e.g., a few, many, or all), damage caused by the earthquake, and casualties caused by the earthquake. Reference Exhibit F-61-1.
Modified Mercalli Intensit 8 number between 1 and 12 that characterizes the severity of ground shaking at a given location by considering the effects of the shaking on people, man-made structures, and the landscape (see Exhibit F-61-1). Intensities will be assigned to most communities in which the earthquake was felt. Intensity values may differ depending on effects in each community.
NWWS: NOAA Weather Wire Service. NOAA Weather Wire Service (NWWS) is a satellite broadcast system that delivers NWS text products to customers.
2. Earthquake Reporting Program. This program is established to disseminate earthquake information within the NWS and to the public. It functions in cooperation with the USGS to increase the effectiveness of the NEIC. The public and especially the NEIC value the information contained in these reports for earthquakes occurring within the United States. Located in Golden, Colorado, the NEIC is a component of the USGS's Office of Earthquakes, Volcanoes, and Engineering, Branch of Global Seismology and Geomagnetism.
2.1 Scope. The procedures described in this Chapter are applicable to all NWS offices in the United States and its possessions, including National Centers, Weather Forecast Offices (WFOs), Weather Service Forecast Offices, Weather Service Offices, Weather Service Meteorological Observatories, NEXRAD Weather Service Forecast Offices , NEXRAD Weather Service Offices, and the Alaska and Pacific Tsunami Warning Centers.
2.2 Reporting Procedures. Distinct reporting procedures are described for the contiguous United States and Puerto Rico, and for offices in Alaska, Hawaii, Guam, American Samoa, the Federated States of Micronesia, the Republic of Palau, and the Republic of the Marshall Islands.
2.2.1 Contiguous United States and Puerto Rico. NWS field offices are often the first to report macroseismic earthquake information to the NEIC. NWS earthquake information reports often trigger the NEIC to investigate an event, sometimes before earthquake data have been calculated from available seismic information. Therefore, NWS earthquake information reports are very important to the NEIC. See Exhibit F-61-2 for product identifiers and dissemination procedures.
Earthquakes of intensity IV or greater on the Modified Mercalli Scale (see Exhibit F-61-1) should be reported immediately to NEIC using AFOS and NWWS (AFOS product identifier CCCEQREQI, WMO abbreviated header SEXX40, see Exhibit F-61-2). Intensity IV is defined as: During the day felt indoors by many, outdoors by few. At night some awakened. Dishes, windows, and doors disturbed; walls make creaking sound. Sensation like heavy truck striking building. Standing motorcars rocked noticeably.
Information contained in the information reports should be factual and validated, if possible. Reports should be in plain language, avoiding abbreviations and local jargon and place names. If the affected area is large, it is possible that independent reports may be issued by several offices for the same event. These reports will be forwarded to the NEIC via the NWWS and the Defense Information Systems Agency AUTODIN system upon receipt from the NOAA Message Center in Silver Spring, Maryland.
Since it may be some time--possibly several hours--before NEIC issues an official press release on an earthquake, each office issuing an Earthquake Information Report shall disseminate it, as soon as possible, over NOAA Weather Radio (NWR), in addition to AFOS and NWWS. Field office personnel should confirm with the NEIC that the event was an earthquake before disseminating the product. If desired, confirmation may be obtained by calling the NEIC duty geophysicist at 303-273-8500 (see Exhibit F-61-3). During off-hours, the answering system will provide the home telephone numbers of the two duty geophysicists on call. Earthquake confirmation is recommended when it is not clear whether the shaking was caused by an earthquake or something else, such as quarry blast, sonic boom, etc.
The NEIC will issue an Earthquake Alert: A General Message (see Exhibits F-61-2 and F-61-4) in accordance with established criteria. Once the message is received by the NWS field office, it should be disseminated on NWR, as soon as possible. Earthquake messages should remain on NWR for two or three cycles. An office may decide to broadcast a message for a longer duration if the earthquake is especially remarkable or if there is significant interest in the event. Note that earthquake information reports issued by NWS field offices contain macroseismic earthquake information and do not contain the Richter Scale magnitude. The Richter Scale magnitude is computed from seismic information (earthquake data) and will be provided by NEIC, as soon as possible. There is no correlation between Mercalli intensity and Richter magnitude.
In addition to the real-time NWS Earthquake Information Reports, the Earthquake Questionnaire (Exhibit F-61-5) provides valuable information to the NEIC after the event. The Questionnaire should be completed and mailed to NEIC within 24 hours of earthquakes which meet the following criteria (Mercalli V):
The questionnaire should be completed and mailed to NEIC for earthquakes that are of sufficient strength at local NWS field offices to knock objects off shelves, displace appliances, crack glass, or be perceived as strong enough to be alarming. Such earthquakes are substantially less frequent than earthquakes that are merely felt. If the earthquake makes a strong impression on the people or significantly displaces objects in an NWS field office, NEIC would like the questionnaire. If there is doubt as to whether the earthquake was sufficiently strong to merit completion of a questionnaire, field personnel can assume no report is needed. A current version of the questionnaire is contained in Exhibit F-61-5.
2.2.1.1 Earthquake Information Report format for AFOS NWWS, and NWR. The NWS Earthquake Information Report should have the following general format:
EARTHQUAKE FELT_____ BY ____ IN ____. _____ DAMAGE _______.
(a) (b) (c) (d) (e)
(a) VERY STRONGLY, STRONGLY, MODERATELY, WEAKLY
(b) (single) OBSERVER, FEW, MANY, etc.
(c) Give locality or localities
(d) CONSIDERABLE, MODERATE, SLIGHT, NO
(E) Give brief description of damage, e.g., CHIMNEYS BROKEN, TOWERS FELL, STRUCTURES DESTROYED, WALLS CRACKED, DISHES RATTLED, BUILDING SHIFTED, CASUALTIES.
In addition, it is necessary to add the following statement at the end of the Earthquake Information Report:
INFORMATION RELEASED IN THIS STATEMENT IS PRELIMINARY. UPDATES, INCLUDING RICHTER SCALE MAGNITUDE, WILL BE MADE AS MORE INFORMATION BECOMES AVAILABLE FROM THE NATIONAL EARTHQUAKE INFORMATION CENTER IN GOLDEN, COLORADO.
See Exhibit F-61-4 for an example of an Earthquake Information Report.
If additional information concerning damage or injuries within the area of the reporting office becomes available within 24 hours of the time of the initial message, supplementary report(s) should be sent to NEIC with this information.
2.2.2 Alaska, Hawaii, Guam, American Samoa, the Federated States of Micronesia, the Republic of Palua, and the Republic of the Marshall Islands. Field offices in Alaska, Hawaii, Guam, American Samoa, the Federated States of Micronesia, the Republic of Palau, and the Republic of the Marshall Islands shall coordinate collection of macroseismic information with the Alaska and Pacific Tsunami Warning Centers 9ATWC and PTWC), respectively. The ATWC and PTWC serve as supporting seisological observatories to the NEIC in addition to their primary function as NWS tsunami warning centers. NWS field offices in Alaska and Hawaii shall communicate earthquake information reports, as outlined in section 2.2.1, to ATWC and PTWC using existing, internal communication circuits. In turn, ATWC and PTWC will transmit earthquake information to NEIC using established communication circuits. WSOM Chapter F-60 (Tsunami Warnign Service) establishes policy for the tsunami warning program and provides additional guidance for the exchange and dissemination of earthquake data. Earthquake reports of macroseismic information only (consolidated, prepared, and disseminated by ATWC and PTWC) for events below the threshold for issuing tsunami information bulletins should follow the report format outlined in section 2.2.1.1. The reports shall be sent to NEIC using established communication circuits and disseminated over NWWS. NWS field offices in the felt area of the earthquake shall broadcast the reports on NWR.
2.3 Request for Reports. Under some circumstances, the NEIC may request macroseismic information reports from NWS offices in a particular area, even if the level of shaking in the NWS office is not of an intensity that would normally warrant issuance of an Earthquake Information Report. Requests should be complied with, as soon as possible, using the Earthquake Information Report format and transmitted as prescribed in sections 2.2.1.1 and 2.2.2.
2.4 NEIC Earthquake Products. Along with macroseismic information provided by the NWS, the NEIC collects additional descriptive and specific technical information to determine the various earthquake parameters. NEIC then issues statements and bulletins for earthquakes occurring both domestically and around the world.
Product identifiers and dissemination procedures for NEIC Earthquake Products are described in Exhibit F-61-2. Examples of these products are displayed in Exhibit F-61-4.
2.5 Customer Outreach. NWS Warning Coordination Meteorologists (WCM) provide and interface between NWS filed offices and customers, including regional, state, county, and local emergency management officials. WCMSs shall maintain a basic understanding of this Chapter, earthquakes in general, and earthquake risks in their area of responsibility, in order to carry out an effective earthquake reporting program in support of the NEIC. This understanding may be obtained through interaction with the NEIC, FEMA Regional Offices, State, County, and Local Emergency Management, local Universities, and other sources of expertise. NWS WCMs should educate their customers, including emergency management officials, on earthquake information disseminated on NWWS and NWR. NWR should be considered an All Hazards dissemination tool. While WCMs are not responsible for being experts on earthquakes, they should assist emergency managers in earthquake preparedness and hazard mitigation activities to the fullest extent possible.
I. Not felt except by a very few under especially favorable circumstances.
II. Felt only by a few persons at rest, especially on upper floors of buildings. Delicately suspended objects may swing. III. Felt quite noticeably indoors, especially on upper floors of buildings, but many people do not recognize it as an earthquake. Standing motorcars may rock slightly. Vibration like passing truck. Duration estimated. IV. During the day felt indoors by many, outdoors by few. At night some awakened. Dishes, windows, and doors disturbed; walls make creaking sound. Sensation like heavy truck striking building. Standing motorcars rocked noticeably. V. Felt by nearly everyone; many awakened. Some dishes, windows, etc. broken; a few instances of cracked plaster; unstable objects overturned. Disturbances of trees, poles, and other tall objects sometimes noticed. Pendulum clocks may stop. VI. Felt by all; many frightened and run outdoors. Some heavy fumiture moved; a few instances of fallen plaster or damaged chimneys. Damage slight. VII. Everybody runs outdoors. Damage negligible in buildings of good design and construction; slight to moderate in well-built ordinary structures; considerable in poorly built or badly designed structures. Some chimneys broken. Noticed by persons driving motorcars. VIII. Damage slight in specially designed structures; considerable in ordinary substantial buildings, with partial collapse; great in poorly built structures. Panel walls thrown out of frame structures. Fall of chimneys, factory stacks, columns, monuments, walls. Heavy furniture overturned. Sand and mud ejected in small amounts. Changes in well water. Persons driving motorcars disturbed. IX. Damage considerable to specially designed structures; well-designed frame structures thrown out of plumb; great in substantial buildings, with partial collapse. Buildings shifted off foundations. Ground cracked conspicuously. Underground pipes broken. X. Some well-built wooden structures destroyed; most masonry and frame structures destroyed with foundations; ground badly cracked. Rails bent. Landslides consider-able from river banks and steep slopes. Shifted sand and mud. Water splashed (slopped) over banks. XI. Few, if any (masonry) structures remain standing. Bridges destroyed. Broad fissures in ground. Underground pipelines completely out of service. Earth slumps and land slips in soft ground. Rails bent greatly. XII. Damage total. Waves seen on ground surfaces. Lines of sight and level distorted. Objects thrown upward into the air. NOTE: This is considered to be a classical scale similar to the Beaufort Scale. Thus a more modem version has not been developed. |
Earthquake Reports Originating from NWS Field Offices:
(Reference section 2.2.1.) Earthquake reports originating from NWS field offices are transmitted using AFOS PIL CCCEQREQI (WMO abbreviated header SEXX40) and addressed to "ALL", where CCC is the node identifier of the parent office. NOTE: It is important to ensure the national product bit has been set to ON (i.e., KEY: CCCEQREQI N=l). The product priority is 4. This product is scheduled for uplinking to the NWWS and broadcast over NWR. Earthquake Information Originating from NEIC: (Reference section 2.4.) The official earthquake information press releases from the NEIC are identified and distributed as follows: EARTHQUAKE ALERT - GENERAL MESSAGE. WMO Header SEXX02 KNEC. NWWS Header NECEQREQS. AFOS Header EQREQS. This is an information message about an earthquake that has met one of the following criteria: (1) magnitude 6.5 or greater, (2) caused or likely to have caused casualties or significant damage, (3) magnitude 4.5 or greater within the contiguous United States, (4) felt strongly enough in the United States to generate inquiries from the news media or public, or (5) other events determined to be newsworthy by the NEIC duty geophysicist. The product contains the location, time of occurrence, magnitude, and felt effects of the earthquake. The product includes a descriptive summary only and is intended for the news media and general public. Note that NWS field offices disseminate the information contained in the Earthquake Alert - General Message over NWR and any other local system in the affected or adjacent areas. EARTHQUAKE ALERT - SCIENTIFIC MESSAGE. WMO Header SEXX01 KNEC. NWWS Header NECEQREQB. AFOS Header EQREQB. This is an information message about an earthquake that has met one of the following criteria: (1) magnitude 5.5 or greater, (2) caused or likely to have caused casualties or significant damage, (3) magnitude 4.5 or greater within the contiguous United States, (4) felt strongly enough in the United States to generate inquiries from the news media or public, or (5) other events determined to be of scientific interest by the NEIC duty geophysicist. The intended audience includes civil defense agencies, dam operators, power plants, railroads, insurance companies, relief agencies, schools, and scientists. The product contains the earthquake location, time of occurrence, magnitude, depth of focus, felt effects, and data used in the processing. QUICK EPICENTER DETERMINATION. WMO Header SEXX03 KNEC. NWWS Header NECEQRQED. AFOS Header EQRQED. This is a global listing of earthquakes that have been located by the NEIC. The listing is issued daily and generally contains 10 to 20 events for the date 7 days prior to the current date. DAILY SUMMARY OF UNITED STATES EARTHQUAKES. WMO Header SEUS42 KNEC. NWWS Header NECEQRSUM. AFOS Header EQRSUM. This is a listing of United States earthquakes that occurred in the last 30 hours, grouped into 6 regions: Southwest, West Central, Northwest, Eastern, Hawaii, and Alaska. This product is available on NWWS. Note that it is not necessary for field offices to redistribute these products on NWWS. Extemal NWWS and Family of Service users should be aware of these products and make necessary arrangements to ensure report as appropriate. See Exhibit F-614 for examples of these products. |
NEIC
The duty geophysicist can be reached at the NEIC facility in Golden, Colorado, by calling (303) 273-8500. An unlisted number, (303) 273-8439, may also be used, but it must remain confidential; do not give it to anyone outside of the NWS
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Example Earthquake Information Report (issued by NWS office):
ZCZC SFOEQREQI EARTHQUAKE REPORT EARTHQUAKE FELT STRONGLY BY MANY IN THE EUREKA AREA AT 320 PM PST. NO MAJOR DAMAGE HAS BEEN REPORTED..HOWEVER..FIRES WERE REPORTED AT FERNDALE, CALIFORNIA. IT HAS BEEN REPORTED BY THE EUREKA FIRE THERE HAVE BEEN AT LEAST EIGHT AFTERSHOCKS..THOUGH MINOR IN STRENGTH. THERE ARE NUMEROUS POWER OUTAGES REPORTED THROUGHOUT THE REGION. INFORMATION RELEASED IN THIS STATEMENT IS PRELIMINARY. UPDATES, INCLUDING RICHTER SCALE MAGNITUDE, WILL BE MADE AS MORE INFORMATION BECOMES AVAILABLE FROM THE NATIONAL EARTHQUAKE INFORMATION CENTER IN GOLDEN, COLORADO.
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Exhibit F-61-4 Example Earthquake Reports
Example Earthquake Alert - General Message (issued by NEIC):
SEXX02 KNEC 261751 THE FOLLOWING IS A RELEASE BY THE U.S. GEOLOGICAL SURVEY, NATIONAL EARTHQUAKE INFORMATION CENTER: A STRONG EARTHQUAKE OCCURRED NEAR THE COAST OF NORTHERN CALIFORNIA, ABOUT 35 MILES SOUTH OF EUREKA AT 5:18 AM MDT TODAY, APRIL 26, 1992. THE MAGNITUDE WAS COMPUTED AT 6.5 ON THE RICHTER SCALE. THE QUAKE WAS RECORDED BY THE U.S. GEOLOGICAL SURVEY AT GOLDEN, COLORADO. THIS EARTHQUAKE IS LOCATED IN THE SAME GENERAL AREA AS THE MAGNITUDE 6.9 EVENT ON APRIL 25. THIS EARTHQUAKE WAS FELT STRONGLY AT EUREKA, SAN FRANCISCO, SACRAMENTO, LAKE TAHOE, AND IN THE SANTA CRUZ-SALINAS AREA. NO REPORTS OF ADDITIONAL DAMAGE OR CASUALTIES HAVE BEEN RECEIVED AT THIS TIME. Example Earthquake Alert - Scientific Message (issued by NEIC): SEXX01 KNEC 190503 STATIONS USED: KMPM P 040337.7 KRMM P 040343.2 KPPM P 040346.4 |
Exhibit F-61-4 Example Earthquake Reports (continued)
MNV P 040451.0 PAGM P 040451.3 MTUM P 040451.9 PMCM P 040452.0 PMGM P 040452.4 PTRM P 040452.7 LON P 040456.3 BCH P 040457.6 YEG P 040458.1 TNP P 040459.2 GMW P 040502.8 ISA P 040506.3 RMW P 040506.4 MCW P 040519.8 GSC P 040524.9 SSK P 040526.9 CSP P 04D528.5 PEC P 040534.3 NEW P 040537.7 HVU P 040540.1 ARUT P 040540.8 DUG P 040540.9 PLM P 040543.5 PTI P 040545.5 MSU P 040551.0 TMI P 040551.5 SMTC P 040555.7 DAU P 040556.6 EMUT P 040602.3 SRU P 040607.9 BW06 P 040612.3 PV09 P 040623.6 PV10 P 040625.3 PV08 P 040628.2 GLD P 040657.3 GOL P 040657.5 RSSD P 040704.5 SIT P 040723.7 CBKS P 040749.3 WMOK P 040811.3 BALM P 040822.9 KLU P 040835.6 SLKM P 040842.2 PMR P 040845.6 MIAR P 040851.0 CRP $0853.0 CP2 P 040854.2 FVM P 040901.8 FBA P 040904.0 SVW P 040904.4 GRT P 040915.2 MFTN P 040915.7 OXF P 040920.4 ANM P 040954.4 OPA P 040955.1 BRW P 041006.5 PRM P 041007.6 YSNY P 041010.9 BLA P 041012.0 JSC P 041014.9 LHS P 041017.1 SSPA P 041018.0 ADK P 041021.2 CVL P 041022.3 SGS P 041023.3 CEH P 041023.7 HBF P 041024.8 BINY P 041026.8 RSNY P 041030.9 GPD P 041039.2 WCC P 041042.8 CRNY P 041043.5 LSCT P 041045.2 LBNH P 041047.3 HRV P 041052.0 SJG P 041252.7 KEV P 041416.7 RAR P 041426.9 LPAZ P 041515.1 PLCA P 041640.5 BGCA P 042215.2 VNDA P 042217.2 BOSA P 042308.2 Example Daily Summary of U.S. Earthquakes (issued by NEIC): UNITED STATES GEOLOGICAL SURVEY SEUS42 LISTS OF U.S. EARTHQUAKES IN THE LAST 30 HOURS EARTHQUAKES IN SOUTHWESTERN UNITED STATES (29.0 TO 35.8 N, 102.0 TO 125.0 W) NO EVENTS LOCATED IN REGION EARTHQUAKES IN WEST CENTRAL UNITED STATES (35.8 TO 40.3 N, 102.0 TO 125.0 W) DATE TIME (UTC) LAT LONG DEPTH MAG |
Exhibit F-61-4 Example Earthquake Reports (continued)
EARTHQUAKES IN NORTHWESTERN UNITED STATES
(40.3 TO 50.0 N, 102.0 TO 125.0 W) NO EVENTS LOCATED IN REGION EARTHQUAKES IN EASTERN UNITED STATES NO EVENTS LOCATED IN REGION EARTHQUAKES IN STATE OF HAWAII NO EVENTS LOCATED IN REGION EARTHQUAKES IN STATE OF ALASKA DATE TIME (UTC) LAT LONG DEPTH MAG 1995 FEB 23 15:59:47.88 58.5 N 153.6 W 100 km 2.9 PREPARED BY USGS/NEIC 1995 FEB 24 AT 00:15 UTC Example Quick Epicenter Determination (issued by NEIC): U.S. DEPARTMENT OF THE INTERIOR SEXX03 FEB 14
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Exhibit F-61-4 Example Earthquake Reports (continued)
102045.1P 14.85 N 93.86 W 33N 4.2 0.8 17 NEAR COAST OF CHIAPAS, MEX 111319.1S 37.777N 42.830E 10G 4.8 4.1 1.1 23 TURKEY 124737.9 35.854N 34.214E 33N 4.2 0.6 37 CYPRUS REG. ML 4.3 (JER). 140422.9P 34.95 S 71.07 W 90G 0.2 10 NEAR COAST OF CEN CHILE 141032.7P 32.43 S 71.61 W 33N 0.6 10 NEAR COAST OF CEN CHILE. MD 3.6 (SAN). 155357.7 23.093S 67.598W 156D 5.7 0.9 130 CHILE-ARG BDR REG. MW 6.0 (GS), 6.0 (HRV). MO=2.2*10**18 NM (PPT). MOMENT TENSOR 171135.5P 31.95 S 70.18 W 110G 0.4 10 CHILE-ARG BDR REG |
Exhibit F-61-4 Example Earthquake Reports (continued)
WSOM Issuance
96-23-6-96