<?xml version="1.0" encoding="UTF-8"?><OAI-PMH xmlns="http://www.openarchives.org/OAI/2.0/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/ http://www.openarchives.org/OAI/2.0/OAI-PMH.xsd"><responseDate>2026-06-11T20:16:40Z</responseDate><request identifier="ATL03.006" metadataPrefix="dif" verb="GetRecord">http://nsidc.org/api/dataset/metadata/oai</request><GetRecord><record><header><identifier>oai:nsidc.org/ATL03.006</identifier><datestamp>2026-02-17T20:03:17Z</datestamp><setSpec>cumulus</setSpec><setSpec>retired</setSpec><setSpec>nasa_nsidc_daac</setSpec></header><metadata>
<DIF xmlns="http://gcmd.gsfc.nasa.gov/Aboutus/xml/dif/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://gcmd.gsfc.nasa.gov/Aboutus/xml/dif/ http://gcmd.gsfc.nasa.gov/Aboutus/xml/dif/dif_v9.7.1.xsd"><Entry_ID>ATL03.006</Entry_ID><Entry_Title>ATLAS/ICESat-2 L2A Global Geolocated Photon Data</Entry_Title><Data_Set_Citation><Dataset_Creator>Neumann, T. A., Brenner, A., Hancock, D., Robbins, J., Gibbons, A., Lee, J., Harbeck, K., Saba, J., Luthcke, S. B. &amp; Rebold, T.</Dataset_Creator><Dataset_Title>ATLAS/ICESat-2 L2A Global Geolocated Photon Data</Dataset_Title><Dataset_Release_Date>2023-05-11</Dataset_Release_Date><Dataset_Release_Place>Boulder, Colorado USA</Dataset_Release_Place><Dataset_Publisher>NASA NSIDC DAAC: NASA National Snow and Ice Data Center Distributed Active Archive Center</Dataset_Publisher><Version>6</Version><Other_Citation_Details><Invert_Citation_Order>false</Invert_Citation_Order></Other_Citation_Details><Dataset_DOI>10.5067/ATLAS/ATL03.006</Dataset_DOI><Online_Resource>https://nsidc.org/sites/default/files/documents/user-guide/atl03-v006-userguide.pdf</Online_Resource><Dataset_Series_Name>ATL03</Dataset_Series_Name></Data_Set_Citation><Personnel><Role>Technical Contact</Role><First_Name>NSIDC</First_Name><Last_Name>User Services</Last_Name><Email>nsidc@nsidc.org</Email><Phone>1-303-492-6199</Phone><Fax>1-303-492-2468</Fax><Contact_Address><Address>CIRES, 449 UCB</Address><Address>University of Colorado</Address><City>Boulder</City><Province_or_State>CO</Province_or_State><Postal_Code>80309-0449</Postal_Code><Country>USA</Country></Contact_Address></Personnel><Parameters><Category>EARTH SCIENCE</Category><Topic>LAND SURFACE</Topic><Term>TOPOGRAPHY</Term><Variable_Level_1>TERRAIN ELEVATION</Variable_Level_1><Variable_Level_2> </Variable_Level_2><Variable_Level_3> </Variable_Level_3><Detailed_Variable> </Detailed_Variable></Parameters><ISO_Topic_Category>Climatology/Meteorology/Atmosphere</ISO_Topic_Category><Keyword>icesat2-project</Keyword><Sensor_Name><Short_Name>ATLAS</Short_Name><Long_Name>Advanced Topographic Laser Altimeter System</Long_Name></Sensor_Name><Source_Name><Short_Name>ICESat-2</Short_Name><Long_Name>Ice, Cloud, and land Elevation Satellite-2</Long_Name></Source_Name><Temporal_Coverage><Start_Date>2018-10-13</Start_Date><Stop_Date>2025-03-03</Stop_Date></Temporal_Coverage><Data_Set_Progress>deprecated</Data_Set_Progress><Spatial_Coverage><Southernmost_Latitude>-90</Southernmost_Latitude><Northernmost_Latitude>90</Northernmost_Latitude><Westernmost_Longitude>-180</Westernmost_Longitude><Easternmost_Longitude>180</Easternmost_Longitude></Spatial_Coverage><Location><Location_Category>GEOGRAPHIC REGION</Location_Category><Location_Type>GLOBAL</Location_Type></Location><Data_Resolution><Latitude_Resolution>70 cm</Latitude_Resolution><Longitude_Resolution>70 cm</Longitude_Resolution><Temporal_Resolution>91 day</Temporal_Resolution></Data_Resolution><Access_Constraints>These data have been retired and are no longer accessible, though a more recent version of these data may be available.</Access_Constraints><Use_Constraints>These data have been retired and are no longer available for use, though a more recent version of these data may be available. Cite any prior or planned use of these data according to the recommended citation at https://nsidc.org/about/data-use-and-copyright. For more information on the NASA ESDIS Data Use Guidance, see&#xA0;https://www.earthdata.nasa.gov/engage/open-data-services-software-policies/data-use-guidance.</Use_Constraints><Data_Set_Language>English</Data_Set_Language><Originating_Center>NASA/GSFC/SED/ESD/I2-SIPS</Originating_Center><Data_Center><Data_Center_Name><Short_Name>NASA NSIDC DAAC</Short_Name><Long_Name>NASA National Snow and Ice Data Center Distributed Active Archive Center</Long_Name></Data_Center_Name><Data_Center_URL>https://nsidc.org/daac</Data_Center_URL><Personnel><Role>Data Center Contact</Role><First_Name>NSIDC</First_Name><Last_Name>User Services</Last_Name><Email>nsidc@nsidc.org</Email><Phone>1-303-492-6199</Phone><Contact_Address><Address>National Snow and Ice Data Center</Address><Address>CIRES, 449 UCB</Address><Address>University of Colorado</Address><City>Boulder</City><Province_or_State>CO</Province_or_State><Postal_Code>80309-0449</Postal_Code><Country>USA</Country></Contact_Address></Personnel></Data_Center><Distribution><Distribution_Media>HTTPS</Distribution_Media><Distribution_Format>HDF5</Distribution_Format></Distribution><Reference/><Summary><Abstract>This data set (ATL03) contains height above the WGS 84 ellipsoid (ITRF2014 reference frame), latitude, longitude, and time for all photons downlinked by the Advanced Topographic Laser Altimeter System (ATLAS) instrument on board the Ice, Cloud and land Elevation Satellite-2 (ICESat-2) observatory. The ATL03 product was designed to be a single source for all photon data and ancillary information needed by higher-level ATLAS/ICESat-2 products. As such, it also includes spacecraft and instrument parameters and ancillary data not explicitly required for ATL03.</Abstract></Summary><Related_URL><URL_Content_Type><Type>VIEW RELATED INFORMATION</Type></URL_Content_Type><URL>https://nsidc.org/sites/default/files/documents/user-guide/atl03-v006-userguide.pdf</URL><Description>ATLAS/ICESat-2 L2A Global Geolocated Photon Data, Version 6 User Guide</Description></Related_URL><Metadata_Name>CEOS IDN DIF</Metadata_Name><Metadata_Version>VERSION 9.9</Metadata_Version><DIF_Creation_Date>2023-05-11</DIF_Creation_Date><Last_DIF_Revision_Date>2026-02-17</Last_DIF_Revision_Date><Extended_Metadata><Metadata><Group>NSIDC</Group><Name>Version Summary</Name><Value>Changes for Version 6 include:
- Added parameters for photon weights
- Updated sigma_h to be dynamically calculated
- Changed data type for ph_id_count to an unsigned 1-byte integer
- Changed the geographic extent metadata from a predicted orbit path to a geodetic polygon
- Updated the ANC42 transmitter echo path reference file to reflect changes in the ATL02 time-of-flight calculations stemming from calibration file updates
- Updated ATL03 photon heights to include an updated zero range point</Value></Metadata><Metadata><Group>NSIDC</Group><Name>Minor Version</Name><Value><number>1</number><summary>Data were reprocessed using ITRF2014 (replacing ITRF2020) for consistency across the entire data set.</summary><start_datetime>2022-11-13</start_datetime><end_datetime>2023-10-26</end_datetime><view_order>0</view_order></Value></Metadata><Metadata><Group>NSIDC</Group><Name>Spatial Reference Systems</Name><Value><Spatial_Reference_System><SRID>EPSG:4326</SRID><Description>WGS 84</Description></Spatial_Reference_System></Value></Metadata><Metadata><Group>NSIDC</Group><Name>Level of Service</Name><Value><Level>No Data Access</Level></Value></Metadata><Metadata><Group>NSIDC</Group><Name>Full Dataset Citation</Name><Value>Neumann, T. A., Brenner, A., Hancock, D., Robbins, J., Gibbons, A., Lee, J., Harbeck, K., Saba, J., Luthcke, S. B. &amp; Rebold, T. (2023). &lt;i&gt;ATLAS/ICESat-2 L2A Global Geolocated Photon Data&lt;/i&gt;. (ATL03, Version 6). [Data Set]. Boulder, Colorado USA. NASA National Snow and Ice Data Center Distributed Active Archive Center. &lt;a href="https://doi.org/10.5067/ATLAS/ATL03.006"&gt;https://doi.org/10.5067/ATLAS/ATL03.006&lt;/a&gt;. [&lt;i&gt;&lt;describe subset used if applicable&gt;&lt;/i&gt;].</Value></Metadata><Metadata><Group>NSIDC</Group><Name>Retired</Name><Value>true</Value></Metadata></Extended_Metadata></DIF>
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