gov.noaa.nodc:0174134 eng utf8 dataset NOAA National Centers for Environmental Information ncei.info@noaa.gov https://www.ncei.noaa.gov/contact HTTPS NOAA Contact Information Information for contacts at NCEI. information custodian 2025-12-14T19:40:25Z ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded Data ISO 19115-2:2009(E) Global stacked sea surface height profiles from AltiKa satellite altimeter data (NCEI Accession 0174134) 2018-08-06 publication 2018-06-26 creation International DOI Foundation (IDF) 10.25921/8hk9-fk45 NOAA National Centers for Environmental Information gov.noaa.nodc:0174134 NCEI Archive Management System 0174134 NOAA National Centers for Environmental Information ncei.info@noaa.gov https://www.ncei.noaa.gov/contact HTTPS NCEI Contact Information Information for contacts at NCEI. information publisher Karen Marks NOAA Center for Satellite Applications and Research (STAR) Karen.Marks@noaa.gov https://www.star.nesdis.noaa.gov/ HTTPS NOAA Center for Satellite Applications and Research (STAR) website Institution web page information resourceProvider NOAA Center for Satellite Applications and Research (STAR) https://www.star.nesdis.noaa.gov/ HTTPS NOAA Center for Satellite Applications and Research (STAR) website Institution web page information resourceProvider Karen Marks NOAA National Environmental Satellite, Data, and Information Service (NESDIS) Karen.Marks@noaa.gov https://www.nesdis.noaa.gov/ HTTPS NOAA National Environmental Satellite, Data, and Information Service (NESDIS) website Institution web page information principalInvestigator Smith, Walter H.F. NOAA National Environmental Satellite, Data, and Information Service (NESDIS) Walter.HF.Smith@noaa.gov https://www.nesdis.noaa.gov/ HTTPS NOAA National Environmental Satellite, Data, and Information Service (NESDIS) website Institution web page information collaborator Marks, Karen M. author Smith, Walter H.F. author NOAA National Environmental Satellite, Data, and Information Service (NESDIS) https://www.nesdis.noaa.gov/ HTTPS NOAA National Environmental Satellite, Data, and Information Service (NESDIS) website Institution web page information contributor tableDigital NetCDF file result_stack.nc contains longitude, latitude, number of cycles, sigma, and stacked sea surface height records for 1002 AltiKa satellite altimeter passes. Repeat cycles were aligned to a common position along a synthetic track having 20005 records between +/-81.498 latitude with equator crossings from the AltiKa median equator crossing table. Stacking is the median sea surface height profile from multiple repeat cycles. Sigma is the expected one sigma error in a single measurement. The number of cycles is the quantity that passed selection criteria and were included in a stack. Cycles were restricted to 1 through 32 due to orbital drift off the nominal ground track after a hardware issue in 2015. Sea surface height data were stacked to reinforce geoid anomalies arising from seafloor topography while reducing noise. completed historicalArchive NOAA National Centers for Environmental Information ncei.info@noaa.gov https://www.ncei.noaa.gov/contact HTTPS NCEI Contact Information Information for contacts at NCEI. information pointOfContact asNeeded https://www.ncei.noaa.gov/access/metadata/landing-page/bin/gfx?id=gov.noaa.nodc:0174134 Preview graphic PNG 0174134 NCEI ACCESSION NUMBER 2018-06-20 publication LATITUDE LONGITUDE SEA HEIGHT theme NODC DATA TYPES THESAURUS AltiKa satellite sensor - altimeter instrument NODC INSTRUMENT TYPES THESAURUS satellite data theme NODC OBSERVATION TYPES THESAURUS SARAL (Satellite with ARgos and ALtiKa) platform NODC PLATFORM NAMES THESAURUS NOAA National Environmental Satellite, Data, and Information Service dataCentre NODC COLLECTING INSTITUTION NAMES THESAURUS NOAA Center for Satellite Applications and Research dataCentre NODC SUBMITTING INSTITUTION NAMES THESAURUS World-Wide Distribution place NODC SEA AREA NAMES THESAURUS oceanography theme WMO_CategoryCode 2012-09-15 publication DOC/NOAA/NESDIS > National Environmental Satellite, Data, and Information Services, NOAA, U.S. Department of Commerce DOC/NOAA/NESDIS/STAR > Center for Satellite Applications and Research, NESDIS, NOAA, U.S. Department of Commerce dataCentre Global Change Master Directory (GCMD) Data Center Keywords 2026 revision 23 Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA) Greenbelt MD https://forum.earthdata.nasa.gov/app.php/tag/GCMD%2BKeywords HTTPS GCMD Keyword Forum Page Global Change Master Directory (GCMD). 2025. GCMD Keywords, Version 21. 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 EARTH SCIENCE > OCEANS > OCEAN WAVES > WAVE HEIGHT theme Global Change Master Directory (GCMD) Science Keywords 2026 revision 23 Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA) Greenbelt MD https://forum.earthdata.nasa.gov/app.php/tag/GCMD%2BKeywords HTTPS GCMD Keyword Forum Page Global Change Master Directory (GCMD). 2025. GCMD Keywords, Version 21. 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 number_of_cycles sigma stacked sea surface height theme Provider Keywords ALTIKA Altimeter > ALTIKA Altimeter ALTIMETERS > ALTIMETERS instrument Global Change Master Directory (GCMD) Instrument Keywords 2026 revision 23 Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA) Greenbelt MD https://forum.earthdata.nasa.gov/app.php/tag/GCMD%2BKeywords HTTPS GCMD Keyword Forum Page Global Change Master Directory (GCMD). 2025. GCMD Keywords, Version 21. 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 SARAL > Satellite with ARgos and ALtiKa platform Global Change Master Directory (GCMD) Platform Keywords 2026 revision 23 Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA) Greenbelt MD https://forum.earthdata.nasa.gov/app.php/tag/GCMD%2BKeywords HTTPS GCMD Keyword Forum Page Global Change Master Directory (GCMD). 2025. GCMD Keywords, Version 21. 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 GEOGRAPHIC REGION > GLOBAL OCEAN place Global Change Master Directory (GCMD) Location Keywords 2026 revision 23 Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA) Greenbelt MD https://forum.earthdata.nasa.gov/app.php/tag/GCMD%2BKeywords HTTPS GCMD Keyword Forum Page Global Change Master Directory (GCMD). 2025. GCMD Keywords, Version 21. 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 XN1B55 Send2NCEI Submission Package ID accessLevel: Public otherRestrictions Cite as: Marks, Karen M.; Smith, Walter H.F. (2018). Global stacked sea surface height profiles from AltiKa satellite altimeter data (NCEI Accession 0174134). [indicate subset used]. NOAA National Centers for Environmental Information. Dataset. https://doi.org/10.25921/8hk9-fk45. Accessed [date]. Distribution liability: NOAA and NCEI make no warranty, expressed or implied, regarding these data, nor does the fact of distribution constitute such a warranty. NOAA and NCEI cannot assume liability for any damages caused by any errors or omissions in these data. If appropriate, NCEI can only certify that the data it distributes are an authentic copy of the records that were accepted for inclusion in the NCEI archives. otherRestrictions Use liability: NOAA and NCEI cannot provide any warranty as to the accuracy, reliability, or completeness of furnished data. Users assume responsibility to determine the usability of these data. The user is responsible for the results of any application of this data for other than its intended purpose. Marks, K. M., & Smith, W. H. F. (2018). A Method of Stacking AltiKa Repeat Cycle Data that May Reveal 75,000+ Possible Small Seamounts. Earth and Space Science, 5(12), 964–969. https://doi.org/10.1029/2018ea000440 2018-12 publication International DOI Foundation (IDF) https://doi.org/10.1029/2018ea000440 https://doi.org/10.1029/2018ea000440 HTTPS https://doi.org/10.1029/2018ea000440 Journal article information Marks, K. M. NOAA Laboratory for Satellite Altimetry College Park MD USA author Smith, W. H. F. NOAA Laboratory for Satellite Altimetry College Park MD USA author American Geophysical Union (AGU) publisher documentDigital Earth and Space Science 5(12) ISSN 2333-5084, ISSN 2333-5084, pp. 964-969 crossReference sciencePaper eng; USA utf8 environment oceans -180 180 -81.5 81.5 2013-03-14 2016-04-07 NOAA National Centers for Environmental Information +1-301-713-3277 ncei.info@noaa.gov pointOfContact In most cases, electronic downloads of the data are free. However, fees may apply for custom orders, data certifications, copies of analog materials, and data distribution on physical media. Contact NCEI for other distribution options and instructions. Originator data format 391.38 https://doi.org/10.25921/8hk9-fk45 HTTPS Web browser NCEI Dataset Landing Page Navigate directly to the URL for a descriptive web page with download links. information https://www.ncei.noaa.gov/archive/accession/oas/174134 HTTPS Web browser Descriptive Information Navigate directly to the URL for a descriptive web page with download links. information https://www.ncei.noaa.gov/archive/accession/download/174134 HTTPS Web browser HTTPS Navigate directly to the URL for data access and direct download. download ftp://ftp-oceans.ncei.noaa.gov/nodc/archive/arc0123/0174134/ FTP Any FTP client FTP These data are available through the File Transfer Protocol (FTP). FTP is no longer supported by most internet browsers. You may copy and paste the FTP link to the data into an FTP client (e.g., FileZilla or WinSCP). download dataset NCEI Accession 0174134 v1.1 was published. 2018-08-06T18:04:51Z NCEI Accession 0174134 v1.1 publication https://www.ncei.noaa.gov/archive/accession/0174134/1.1 HTTPS NCEI Accession 0174134 v1.1 published 2018-08-06T18:04:51Z download dataset Parameter or Variable: LONGITUDE (calculated); Units: degrees E; Observation Category: model output; Sampling Instrument: satellite sensor - altimeter; Sampling and Analyzing Method: AltiKa repeat cycles are aligned to a common position along a synthetic track having 20005 records between +/-81.498 latitude with equator crossings from the AltiKa median equator crossing table. East longitude relative to Greenwich meridian. Positive longitude is East longitude, negative longitude is West longitude. Parameter or Variable: LATITUDE (calculated); Units: degrees N; Observation Category: model output; Sampling Instrument: satellite sensor - altimeter; Sampling and Analyzing Method: AltiKa repeat cycles are aligned to a common position along a synthetic track having 20005 records between +/-81.498 latitude with equator crossings from the AltiKa median equator crossing table. Positive latitude is North latitude, negative latitude is South latitude. Parameter or Variable: Number of Cycles (calculated); Units: cycles; Observation Category: other; Sampling Instrument: satellite sensor - altimeter; Sampling and Analyzing Method: Each of 1002 AltiKa passes has up to 32 cycles selected for this analysis. The number of cycles is the quantity used in the stack for each pass. Parameter or Variable: Sigma (calculated); Units: meters; Observation Category: model output; Sampling Instrument: satellite sensor - altimeter; Sampling and Analyzing Method: Sigma is expected error in a single measurement. Sigma of the stack = sigma/sqrt((2N+1)/3), where N = number of cycles Parameter or Variable: Stacked sea surface height (calculated); Units: meters; Observation Category: model output; Sampling Instrument: satellite sensor - altimeter; Sampling and Analyzing Method: Stacked sea surface height is the median sea surface height profile from multiple repeat cycles. asNeeded Metadata are developed, maintained and distributed by NCEI. Updates are performed as needed to maintain currentness. NOAA National Centers for Environmental Information custodian AltiKa AltiKa Ka-band Altimeter AltiKa is a Ka-band altimeter (35 GHz) developed by CNES (Space Agency of France) on-board the Satellite with ARgos and ALtiKa (SARAL). It is the first space-born ocean surface topography instrument using such a high frequency. The use of the Ka-band frequency will supply more accurate measurements (improvement of the spatial and vertical resolution of the ocean surface topography observations), enabling a better observation of ice, coastal areas, continental water bodies as well as wind and waves height. SARAL is a French and Indian collaborative mission to measure sea surface height using the Ka-band AltiKa altimeter and was launched on February 25, 2013. Additional Information: http://www.aviso.altimetry.fr/en/missions/present-missions/saral/instruments/altika-a-ka-band-altimeter.html https://altika-saral.cnes.fr/en/SARAL/altika.htm satellite sensor - altimeter satellite sensor - altimeter satellite sensor - altimeter SARAL (Satellite with ARgos and ALtiKa) Platform Class: 65-Orbiting satellite Synonyms: Satellite with ARgos and ALtiKa Launched Date: 2013-02-25 Commissioned Date: 2013-03-13 Decommissioned Date (YYYY-MM-DD): Notes: Satellite with ARgos and ALtiKa (SARAL) is a cooperative altimetry technology mission of Indian Space Research Organization(ISRO) and CNES (Space Agency of France). SARAL performs altimetric measurements designed to study ocean circulation and sea surface elevation. The payloads of SARAL are the ISRO built satellite with payloads modules (ALTIKA altimeter), DORIS, Laser Retro-reflector Array (LRA) and Advanced Research and Global Observation Satellite (ARGOS) data collection system provided by CNES. ISRO is responsible for the platform, launch, and operations of the spacecraft. The overall objectives of SARAL are to realize precise, repetitive global measurements of sea surface height, significant wave heights and wind speed for: 1)Development of operational oceanography (study of mesoscale ocean viability, coastal region observations, inland waters, marine ecosystems, etc. ); 2) Understanding of climate and developing forecasting capabilities and 3)Operational meteorology. Info Source: https://directory.eoportal.org/web/eoportal/satellite-missions/s/saral https://altika-saral.cnes.fr/en/SARAL/GP_satellite.htm http://www.isro.gov.in/Spacecraft/saral