gov.noaa.ngdc.mgg.hazards:G02151 eng; USA utf8 dataset NOAA National Centers for Environmental Information Hazards Data Manager haz.info@noaa.gov pointOfContact 2024-09-10 ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded Data ISO 19115-2:2009(E) NCEI/WDS Global Historical Tsunami Database, 2100 BC to Present 1974-01-01 publication doi:10.7289/V5PN93H7 NOAA National Centers for Environmental Information publisher National Geophysical Data Center / World Data Service (NGDC/WDS) originator Nicolas Arcos DOC/NOAA/NESDIS/NCEI > National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce (303) 497-3158 (303) 497-6513 325 Broadway, Mail Code E/NE42 Boulder CO 80305-3328 USA haz.info@noaa.gov pointOfContact https://www.ngdc.noaa.gov/hazard/tsu_db.shtml http NCEI/WDS Global Historical Tsunami Database, 2100 BC to Present Information on tsunami events from 2100 BC to the present in the Atlantic, Indian, and Pacific Oceans; and the Mediterranean and Caribbean Seas. information mapDigital tableDigital The Global Historical Tsunami Database provides information on over 2,400 tsunamis from 2100 BC to the present in the the Atlantic, Indian, and Pacific Oceans; and the Mediterranean and Caribbean Seas. The database includes two related files. The first file includes information on the tsunami source such as the date, time, and location of the source event; cause and validity of the source, tsunami magnitude and intensity; maximum water height; the total number of fatalities, injuries, houses destroyed, and houses damaged; and total damage estimate (in U.S. dollars). The second related file contains information on the runups (the locations where tsunami waves were observed by eyewitnesses, reconnaissance surveys, tide gauges, and deep-ocean sensors) such as name, location, arrival time, maximum water height and inundation distance, and socio-economic data (deaths, injuries, damage) for the specific runup location. These data are necessary for tsunami hazard assessments, mitigation efforts, and warning guidance. onGoing Nicolas Arcos DOC/NOAA/NESDIS/NCEI > National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce (303) 497-3158 (303) 497-6513 325 Broadway, Mail Code E/NE42 Boulder CO 80305-3328 USA haz.info@noaa.gov pointOfContact asNeeded https://www.ngdc.noaa.gov/hazard/icons/tsunamis.jpg Maps showing tsunami events and tsunami runups and locations. jpg Earth Science > Oceans > Ocean Waves > Tsunamis theme Global Change Master Directory (GCMD) Science Keywords 2024 revision 19 Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA) https://forum.earthdata.nasa.gov/app.php/tag/GCMD%2BKeywords GCMD Keyword Forum Page Global Change Master Directory (GCMD). 2024. GCMD Keywords, Version 19. Greenbelt, MD: Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA). URL (GCMD Keyword Forum Page): https://forum.earthdata.nasa.gov/app.php/tag/GCMD+Keywords information custodian Disasters > Catastrophic Phenomena > Tsunami theme INFOTERRA Keyword Thesaurus ICSU-WDS > International Council for Science - World Data System project Global Change Master Directory (GCMD) Project Keywords 2020-01-09 publication 9.1 Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA) https://forum.earthdata.nasa.gov/app.php/tag/GCMD%2BKeywords GCMD Keyword Forum Page Global Change Master Directory (GCMD). 2024. GCMD Keywords, Version 19. Greenbelt, MD: Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA). URL (GCMD Keyword Forum Page): https://forum.earthdata.nasa.gov/app.php/tag/GCMD+Keywords information custodian Global place Global Change Master Directory (GCMD) Location Keywords 2024 revision 19 Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA) https://forum.earthdata.nasa.gov/app.php/tag/GCMD%2BKeywords GCMD Keyword Forum Page Global Change Master Directory (GCMD). 2024. GCMD Keywords, Version 19. Greenbelt, MD: Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA). URL (GCMD Keyword Forum Page): https://forum.earthdata.nasa.gov/app.php/tag/GCMD+Keywords information custodian DOC/NOAA/NESDIS/NCEI > National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce DOC/NOAA/NESDIS/NGDC > National Geophysical Data Center, NESDIS, NOAA, U.S. Department of Commerce dataCentre Global Change Master Directory (GCMD) Data Center Keywords 2020-01-09 publication 9.1 Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA) https://forum.earthdata.nasa.gov/app.php/tag/GCMD%2BKeywords GCMD Keyword Forum Page Global Change Master Directory (GCMD). 2024. GCMD Keywords, Version 19. Greenbelt, MD: Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA). URL (GCMD Keyword Forum Page): https://forum.earthdata.nasa.gov/app.php/tag/GCMD+Keywords information custodian otherRestrictions Cite as: National Geophysical Data Center / World Data Service: NCEI/WDS Global Historical Tsunami Database. NOAA National Centers for Environmental Information. doi:10.7289/V5PN93H7 [access date] otherRestrictions Access to this dataset is unrestricted. otherRestrictions While every effort has been made to ensure that these data are accurate and reliable within the limits of the current state of the art, NOAA cannot assume liability for any damages caused by any errors or omissions in the data, nor as a result of the failure of the data to function on a particular system. NOAA makes no warranty, expressed or implied, nor does the fact of distribution constitute such a warranty. NCEI/WDS Global Significant Earthquake Database, 2150 BC to Present 1972-01-01 publication doi:10.7289/V5TD9V7K partOfSeamlessDatabase collection NCEI/WDS Global Significant Volcanic Eruptions Database, 4360 BC to Present 2001-03-23 publication doi:10.7289/V5JW8BSH partOfSeamlessDatabase collection NCEI/WDS Global Tsunami Deposits Database 2001-03-23 publication gov.noaa.ngdc.mgg.hazards:G10146 crossReference collection Size of great earthquakes of 1837-1974 inferred from tsunami data. 1979-01-01 publication doi:10.1029/JB084iB04p01561 Abe, Katsuyuki author Journal of Geophysical Research 84(B4) pp. 1561-1568 crossReference sciencePaper Magnitudes of Large Shallow Earthquakes from 1904 to 1980. 1981-01-01 publication doi:10.1016/0031-9201(81)90088-1 Abe, Katsuyuki author Physics of the Earth and Planetary Interiors 27 pp. 72-92 crossReference sciencePaper Preliminary Catalog of Tsunamis Occurring in the Pacific Ocean 1967-12-01 publication Iida, Kumizi author Cox, Doak C. author Pararas-Carayannis, George author Hawaii Institute of Geophysics Report HIG-67-10 275 p. crossReference sciencePaper eng; USA oceans geoscientificInformation -180 180 -63 71 -2100 Tsunami Source Date physicalMeasurement Tsunami Source Location physicalMeasurement Source Latitude Distance measured north or south from the equator. Distance north is positive, distance south is negative. 90.00000 -90.00000 decimal degrees decimal degrees Source Longitude Longitude is measured from the Prime Meridian (which is the north/south line that runs through Greenwich, England), values measured east are positive and values measured west are negative. 180.00000 -180.00000 decimal degrees decimal degrees Source Country The country in which the source event of the tsunami occurred. Source Region The global region in which the source event of the tsunami occurred. Tsunami Cause physicalMeasurement Validity of Tsunami Validity of the actual tsunami occurrence is indicated by a numerical rating of the reports of that event 4 = definite tsunami 3 = probable tsunami 2 = questionable tsunami 1 = very doubtful tsunami 0 = event that only caused a seiche or disturbance in an inland river -1 = erroneous entry Cause of Tsunami (Code) The source of the tsunami. 0 = Unknown 1 = Earthquake 2 = Questionable Earthquake 3 = Earthquake and Landslide 4 = Volcano and Earthquake 5 = Volcano, Earthquake, and Landslide 6 = Volcano 7 = Volcano and Landslide 8 = Landslide 9 = Meteorological 10 = Explosion 11 = Astronomical Tide Tsunami Characteristics physicalMeasurement Maximum Water Height of All Runups The maximum water height above sea level in meters for this event. If the type of measurement of the runup was a: Tide Gauge - half of the maximum height (minus the normal tide)of a tsunami wave recorded at the coast by a tide gauge. Runup Height - the maximum elevation the wave reaches at the maximum inundation. meters meters Number of Runups The total number of runups link will display the runup locations associated with a particular tsunami event. Tsunami Magnitude (Abe) Abe defined two different tsunami magnitude amplitudes. His first tsunami magnitude (1979) is: Mt = logH + B, where H is the maximum single crest or trough amplitude of the tsunami waves (in meters) and B a constant. The second definition (1981) is: Mt = logH + alogR + D, where R is the distance in km from the earthquake epicenter to the tide station along the shortest oceanic path, and a and D are constants. Tsunami Magnitude (Iida) Tsunami magnitude (M) is defined by Iida and others (1967) as M = log2h, where "h" is the maximum runup height of the wave. Tsunami Intensity Tsunami intensity is defined by Soloviev and Go (1974) as I = log2(21/2 * h), where "h" is the maximum runup height of the wave. Tsunami Runup Measurements physicalMeasurement Tsunami Runup Latitude The latitude of the observed tsunami runup. Distance measured north or south from the equator. Distance north is positive, distance south is negative. 90.00000 -90.00000 decimal degrees decimal degrees Tsunami Runup Longitude The longitude of the observed tsunami runup. Longitude is measured from the Prime Meridian (which is the north/south line that runs through Greenwich, England), values measured east are positive and values measured west are negative. 180.00000 -180.00000 decimal degrees decimal degrees Tsunami Runup Country The country where the tsunami effects were observed. Tsunami Runup State The State, Province or Prefecture where the tsunami effects were observed. Tsunami Runup Location Name The location (city, state or island) where the tsunami effects were observed. Distance from Source The distance from the tsunami event source to the runup location. kilometers kilometers Initial Wave Arrival Time The arrival time is the universal coordinated time of the arrival of the initial tsunami wave at the location of the effects given in Day, Hour and Minutes. Initial Wave Travel Time The travel time is the time in hours and minutes that it took the initial tsunami wave to travel from the source to the location of effects. Maximum Water Height The maximum water height above sea level in meters for this runup. If the type of measurement of the runup was a: Tide Gauge - half of the maximum height (minus the normal tide)of a tsunami wave recorded at the coast by a tide gauge. Runup Height - the maximum elevation the wave reaches at the maximum inundation. meters meters Maximum Indundation Distance The maximum horizontal distance of inland flooding (in meters) meters meters Period The period is in minutes and, when available, is the period of the first cycle. minutes minutes Number of Deaths from the Tsunami at this Location If an actual number of deaths due to the tsunami is known, enter a number in this search field. If only a description is available such as "few", "some", or "many", the database can be searched using the search field: Death Description. Number of Injuries from the Tsunami at this Location Whenever possible, numbers of injuries from the tsunami are listed. Damage in Millions of Dollars from the Tsunami at this Location The value in the Damage column should be multiplied by 1,000,000 to obtain the actual dollar amount. If an actual number of dollars in damage due to the tsunami is known, enter a number in this search field. If only a description is available such as "limited", "moderate", or "severe", the database can be searched using the search field:Damage Description. When a dollar amount for damage was found in the literature, it was listed in the Damage column in millions of U.S. dollars. The dollar value listed is the value at the time of the event. To convert the damage to current dollar values, please use the Consumer Price Index Calculator. Monetary conversion tables for the time of the event were used to convert foreign currency to U.S. dollars. Number of Houses Destroyed by the Tsunami at this Location Whenever possible, number of houses destroyed by the tsunami are listed. Number of Houses Damaged by the Tsunami at this Location Whenever possible, number of houses damaged by the tsunami are listed. Type of Measurement The type of measurement used to determine the tsunami runup at this location. 1 = Eyewitness measurement 2 = Tide-gauge measurement 3 = Deep ocean gauge 4 = Water height, Post-tsunami survey measurement 5 = Runup Height, Post-tsunami survey measurement 6 = Atmospheric Wave 7 = Seiche 8 = Water height in harbor, Post-tsunami survey measurement 9 = Splash mark, Post-tsunami survey measurement 10 = Flow Depth, Post-tsunami survey measurement First Motion The first motion of the wave whether rise or fall. R = Rise F = Fall Description of Number of Deaths from the Tsunami at this Location When a description was found in the historical literature instead of an actual number of deaths, this value was coded and listed in the Deaths De column. If the actual number of deaths was listed, a descriptor was also added for search purposes. 0 = None 1 = Few (~1 to 50 deaths) 2 = Some (~51 to 100 deaths) 3 = Many (~101 to 1000 deaths) 4 = Very Many (~1001 or more deaths) Description of Number of Injuries from the Tsunami at this Location When a description was found in the historical literature instead of an actual number of injuries, this value was coded and listed in the Injuries De column. If the actual number of injuries was listed, a descriptor was also added for search purposes. 0 = None 1 = Few (~1 to 50 injuries) 2 = Some (~51 to 100 injuries) 3 = Many (~101 to 1000 injuries) 4 = Very Many (~1001 or more injuries) Description of Damage from the Tsunami at this Location For those events not offering a monetary evaluation of damage, the following five-level scale was used to classify damage (1990 dollars) and was listed in the Damage De column. If the actual dollar amount of damage was listed, a descriptor was also added for search purposes. When possible, a rough estimate was made of the dollar amount of damage based upon the description provided, in order to choose the damage category. In many cases, only a single descriptive term was available. These terms were converted to the damage categories based upon the authors apparent use of the term elsewhere. In the absence of other information, LIMITED is considered synonymous with slight, minor, and light, SEVERE as synonymous with major, extensive, and heavy, and EXTREME as synonymous with catastrophic. Note: The descriptive terms relate approximately to current dollar values. 0 = NONE 1 = LIMITED (roughly corresponding to less than $1 million) 2 = MODERATE (~$1 to $5 million) 3 = SEVERE (~>$5 to $24 million) 4 = EXTREME (~$25 million or more) Description of Number of Houses Destroyed by the Tsunami at this Location For those events not offering an exact number of houses destroyed, the following four-level scale was used to classify the destruction and was listed in the Houses Destroyed De column. If the actual number of houses destroyed was listed, a descriptor was also added for search purposes. 0 = None 1 = Few (~1 to 50 houses) 2 = Some (~51 to 100 houses) 3 = Many (~101 to 1000 houses) 4 = Very Many (~1001 or more houses) Description of Number of Houses Damaged by the Tsunami at this Location For those events not offering an exact number of houses damaged, the following four-level scale was used to classify the damage and was listed in the Houses Damaged De column. If the actual number of houses destroyed was listed, a descriptor was also added for search purposes. 0 = None 1 = Few (~1 to 50 houses) 2 = Some (~51 to 100 houses) 3 = Many (~101 to 1000 houses) 4 = Very Many (~1001 or more houses) Overall Tsunami Effects physicalMeasurement Number of Deaths from the Tsunami If an actual number of deaths due to the tsunami is known, enter a number in this search field. If only a description is available such as "few", "some", or "many", the database can be searched using the search field: Death Description. Number of Injuries from the Tsunami Whenever possible, numbers of injuries from the tsunami are listed. Damage in Millions of Dollars from the Tsunami The value in the Damage column should be multiplied by 1,000,000 to obtain the actual dollar amount. If an actual number of dollars in damage due to the tsunami is known, enter a number in this search field. If only a description is available such as "limited", "moderate", or "severe", the database can be searched using the search field:Damage Description. When a dollar amount for damage was found in the literature, it was listed in the Damage column in millions of U.S. dollars. The dollar value listed is the value at the time of the event. To convert the damage to current dollar values, please use the Consumer Price Index Calculator. Monetary conversion tables for the time of the event were used to convert foreign currency to U.S. dollars. Number of Houses Destroyed by the Tsunami Whenever possible, number of houses destroyed by the tsunami are listed. Number of Houses Damaged by the Tsunami Whenever possible, number of houses damaged by the tsunami are listed. Description of Number of Deaths from the Tsunami When a description was found in the historical literature instead of an actual number of deaths, this value was coded and listed in the Deaths De column. If the actual number of deaths was listed, a descriptor was also added for search purposes. 0 = None 1 = Few (~1 to 50 deaths) 2 = Some (~51 to 100 deaths) 3 = Many (~101 to 1000 deaths) 4 = Very Many (~1001 or more deaths) Description of Number of Injuries from the Tsunami When a description was found in the historical literature instead of an actual number of injuries, this value was coded and listed in the Injuries De column. If the actual number of injuries was listed, a descriptor was also added for search purposes. 0 = None 1 = Few (~1 to 50 injuries) 2 = Some (~51 to 100 injuries) 3 = Many (~101 to 1000 injuries) 4 = Very Many (~1001 or more injuries) Description of Damage from the Tsunami For those events not offering a monetary evaluation of damage, the following five-level scale was used to classify damage (1990 dollars) and was listed in the Damage De column. If the actual dollar amount of damage was listed, a descriptor was also added for search purposes. 0 = NONE 1 = LIMITED (roughly corresponding to less than $1 million) 2 = MODERATE (~$1 to $5 million) 3 = SEVERE (~>$5 to $24 million) 4 = EXTREME (~$25 million or more) Description of Number of Houses Destroyed by the Tsunami For those events not offering an exact number of houses destroyed, the following four-level scale was used to classify the destruction and was listed in the Houses Destroyed De column. If the actual number of houses destroyed was listed, a descriptor was also added for search purposes. 0 = None 1 = Few (~1 to 50 houses) 2 = Some (~51 to 100 houses) 3 = Many (~101 to 1000 houses) 4 = Very Many (~1001 or more houses) Description of Number of Houses Damaged by the Tsunami For those events not offering an exact number of houses damaged, the following four-level scale was used to classify the damage and was listed in the Houses Damaged De column. If the actual number of houses destroyed was listed, a descriptor was also added for search purposes. 0 = None 1 = Few (~1 to 50 houses) 2 = Some (~51 to 100 houses) 3 = Many (~101 to 1000 houses) 4 = Very Many (~1001 or more houses) TSV NOAA National Centers for Environmental Information Hazards Data Manager haz.info@noaa.gov pointOfContact Free online https://www.ngdc.noaa.gov/hazel/view/hazards/tsunami/event-search http Tsunami Event Database Provides information on the tsunami source including date, time, event location, magnitude of the phenomenon, maximum wave height, and socio-economic information such as the total number of fatalities and dollar damage estimates if available. If the tsunami source was an earthquake or volcanic eruption, it is flagged and linked to the related database. search https://www.ngdc.noaa.gov/hazel/view/hazards/tsunami/runup-search http Tsunami Runup Database Provides information on locations where tsunami waves were observed by eyewitnesses, post-tsunami field surveys, tide gauges, or deep ocean sensors. Includes the maximum wave height, inundation distance, and number of fatalities or dollar damage estimates at the specific location if available. search https://www.ncei.noaa.gov/maps/hazards/ http Natural Hazards Map Viewer Tsunami source and runup locations, significant earthquake epicenters, significant volcanic eruption locations. search https://www.ngdc.noaa.gov/hazel/view/hazards/tsunami/event-search http Tsunami Event Database Provides information on the tsunami source including date, time, event location, magnitude of the phenomenon, maximum wave height, and socio-economic information such as the total number of fatalities and dollar damage estimates if available. If the tsunami source was an earthquake or volcanic eruption, it is flagged and linked to the related database. download https://www.ngdc.noaa.gov/hazel/view/hazards/tsunami/runup-search http Tsunami Runup Database Provides information on locations where tsunami waves were observed by eyewitnesses, post-tsunami field surveys, tide gauges, or deep ocean sensors. Includes the maximum wave height, inundation distance, and number of fatalities or dollar damage estimates at the specific location if available. download https://www.ngdc.noaa.gov/hazard/ Natural Hazards Website Data, products and services for natural hazards. information dataset First computerized tsunami database started in 1970s with ascii files with descriptions that were separate to eventually searchable ascii and finally databases. In 1980s, NGDC began compilation of quantitative tsunami data from all available catalogs and special studies of tsunamis. In the 1908s the original database only covered the Pacific. The current NCEI/WDS Global Historical Tsunami Database includes two related tables: global observations of tsunami sources and tsunami runup records (locations where tsunami waves were observed by eyewitnesses, field reconnaissance surveys, tide gauges or deep-ocean sensors). The historical database incorporates, where available, maximum tsunami wave heights for each coastal tide gauge and deep-ocean buoy that recorded a tsunami signal. The database is now updated regularly from sources such as NOAA Tsunami Warning Centers, NOAA National Data Buoy Center, NOAA National Ocean Service, UNESCO/IOC-NOAA International Tsunami Information Center, NOAA Pacific Marine Environmental Laboratory, U.S. Geological Survey, national and government databases and reports, tsunami catalogs, post-event reconnaissance reports, journal articles, newspapers, internet sources, email, and other written documents. The database is updated upon the availability of new tsunami data. Natural Hazards Data Manager DOC/NOAA/NESDIS/NCEI > National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce custodian The database is updated regularly from sources such as NOAA Tsunami Warning Centers, NOAA National Data Buoy Center, NOAA National Ocean Service, UNESCO/IOC-NOAA International Tsunami Information Center, NOAA Pacific Marine Environmental Laboratory, U.S. Geological Survey, national and government databases and reports, tsunami catalogs, post-event reconnaissance reports, journal articles, newspapers, internet sources, email, and other written documents. dataset Erroneous statistical conclusions can be drawn from the numbers of earthquakes taken from Catalog of Significant Earthquakes, 2150 B.C. to the present. The reporting of large or destructive earthquakes is not homogeneous in space or time, particularly for periods prior to the 1900s. Because this publication mainly lists those earthquakes that have caused death or damage, the number of earthquake reports is dependent on the written history available for a particular region, as well as on the rate of development of population centers and related structures. Therefore, it is misleading to use the numbers of significant earthquakes in that publication to suggest statistically that there has been an increase in worldwide seismic activity since 1900 or for any time period. that "apparent" increase in activity: Instrumental seismology is a young science. The first calibrated instruments to measure seismic waves traveling through the earth did not appear until the late 1800s. At that time, seismologists became aware of the vast numbers of earthquakes occurring throughout the world, but because of the insensitivity of their instruments they were able to locate only the large magnitude events. The 1960s saw two major advances. First, a network of seismological observatories, the Worldwide Standardized Seismograph Network (WWSSN), was installed by the United States Government, principally to monitor underground nuclear tests. These sensitive instruments could detect and identify earthquakes anywhere in the world from about magnitude 4.5. Second computers became available in the late 1960s. Computers allowed seismologists to leave inaccurate and cumbersome graphical methods of locating earthquakes, and to process the increasing volume of new network data more rapidly than ever before. Prior to 1962, only hundreds of earthquake epicenters were determined each year by Government and academic institutions, but the number increased to the thousands using computerized location methods. In some special local studies, more than 100,000 earthquakes per year were identified and located. In summary, using the data in Catalog of Significant Earthquakes, 2150 B.C. to the present to suggest that there has been an increase in worldwide earthquake activity is misleading and erroneous. The above observations and reporting factors must also be considered when making statistical studies based on that historical data report. The same problems that can lead to erroneous statistics discussed above, also introduce uncertainties in the earthquake and tsunami databases for events prior to the late 1800s, and in some areas for events prior to the installation of the WWSSN in 1962. Before the invention of seismographs in the late 1800s magnitudes, times and locations of earthquakes and tsunami sources were determined from descriptions of earthquake damage and tsunami effects. Earthquake epicenters and tsunami source locations may have been assigned to the wrong places when the names of localitieis were incorrectly transcribed or when some localities had identical or very similar names. Errors may have also been introduced when the local times of earthquakes and tsunami reports were incorrectly converted to Universal Coordinated Time by catalogers. Earthquake and tsunami events can also be listed twice when the dates are recorded in different sources according to the Julian or the Gregorian calendars. As a result, the earthquake and tsunami databases may include listings of events on different dates that are actually descriptions of the same event. For a more complete discussion of these errors please see Historical Seismograms and Earthquakes of the World, edited by W.H.K. Lee, H. Meyers and K. Shimzaki, 1988, Academic Press, Inc., San Diego, California, 513 p. The tsunami database may also include errors that are unique to that database. One of the most important measurements associated with a tsunami event is the maximum runup height or water height reached above sea level in meters. Unfortunately, it is not always clear which reference level was used. The tsunami database also includes locations where the tsunami was observed, called runup locations. The same problem that occurs when identifying earthquake epicenters can occur when assigning runup locations, where the names of localities were incorrectly transcribed or where some localities had identical or very similar names. In addition, names of locations can change over time adding to the possibility of errors. If tsunami arrival and travel times are available for specific runup locations, they are included in the database. These data are valuable in verifying tsunami travel time models. The definition used in this database is the arrival or travel time of the first wave that arrives at a runup location. The first wave may not have been the largest wave, therefore the travel time reported in the original source may have been the second or third wave. Erroneous statistical conclusions can be drawn from the numbers of earthquakes taken from Catalog of Significant Earthquakes, 2150 B.C. to the present. The reporting of large or destructive earthquakes is not homogeneous in space or time, particularly for periods prior to the 1900s. Because this publication mainly lists those earthquakes that have caused death or damage, the number of earthquake reports is dependent on the written history available for a particular region, as well as on the rate of development of population centers and related structures. Therefore, it is misleading to use the numbers of significant earthquakes in that publication to suggest statistically that there has been an increase in worldwide seismic activity since 1900 or for any time period. that "apparent" increase in activity: Instrumental seismology is a young science. The first calibrated instruments to measure seismic waves traveling through the earth did not appear until the late 1800s. At that time, seismologists became aware of the vast numbers of earthquakes occurring throughout the world, but because of the insensitivity of their instruments they were able to locate only the large magnitude events. The 1960s saw two major advances. First, a network of seismological observatories, the Worldwide Standardized Seismograph Network (WWSSN), was installed by the United States Government, principally to monitor underground nuclear tests. These sensitive instruments could detect and identify earthquakes anywhere in the world from about magnitude 4.5. Second computers became available in the late 1960s. Computers allowed seismologists to leave inaccurate and cumbersome graphical methods of locating earthquakes, and to process the increasing volume of new network data more rapidly than ever before. Prior to 1962, only hundreds of earthquake epicenters were determined each year by Government and academic institutions, but the number increased to the thousands using computerized location methods. In some special local studies, more than 100,000 earthquakes per year were identified and located. In summary, using the data in Catalog of Significant Earthquakes, 2150 B.C. to the present to suggest that there has been an increase in worldwide earthquake activity is misleading and erroneous. The above observations and reporting factors must also be considered when making statistical studies based on that historical data report. The same problems that can lead to erroneous statistics discussed above, also introduce uncertainties in the earthquake and tsunami databases for events prior to the late 1800s, and in some areas for events prior to the installation of the WWSSN in 1962. Before the invention of seismographs in the late 1800s magnitudes, times and locations of earthquakes and tsunami sources were determined from descriptions of earthquake damage and tsunami effects. Earthquake epicenters and tsunami source locations may have been assigned to the wrong places when the names of localitieis were incorrectly transcribed or when some localities had identical or very similar names. Errors may have also been introduced when the local times of earthquakes and tsunami reports were incorrectly converted to Universal Coordinated Time by catalogers. Earthquake and tsunami events can also be listed twice when the dates are recorded in different sources according to the Julian or the Gregorian calendars. As a result, the earthquake and tsunami databases may include listings of events on different dates that are actually descriptions of the same event. For a more complete discussion of these errors please see Historical Seismograms and Earthquakes of the World, edited by W.H.K. Lee, H. Meyers and K. Shimzaki, 1988, Academic Press, Inc., San Diego, California, 513 p. The tsunami database may also include errors that are unique to that database. One of the most important measurements associated with a tsunami event is the maximum runup height or water height reached above sea level in meters. Unfortunately, it is not always clear which reference level was used. The tsunami database also includes locations where the tsunami was observed, called runup locations. The same problem that occurs when identifying earthquake epicenters can occur when assigning runup locations, where the names of localities were incorrectly transcribed or where some localities had identical or very similar names. In addition, names of locations can change over time adding to the possibility of errors. If tsunami arrival and travel times are available for specific runup locations, they are included in the database. These data are valuable in verifying tsunami travel time models. The definition used in this database is the arrival or travel time of the first wave that arrives at a runup location. The first wave may not have been the largest wave, therefore the travel time reported in the original source may have been the second or third wave. repository NOAA National Centers for Environmental Information NOAA created the National Centers for Environmental Information (NCEI) by merging NOAA's National Climatic Data Center (NCDC), National Geophysical Data Center (NGDC), and National Oceanographic Data Center (NODC), including the National Coastal Data Development Center (NCDDC), per the Consolidated and Further Continuing Appropriations Act, 2015, Public Law 113-235. NCEI launched publicly on April 22, 2015. 2015-04-22T00:00:00 unknown This record was automatically modified on 2015-10-01 to include references to NCEI where applicable. The title and citation statement were changed from NGDC to NCEI on 2018-06-07 because NCEI is the current publisher. NOAA National Centers for Environmental Information Metadata Specialist editor