edu.ucar.opensky::articles:24307 UCAR/NCAR - Library OpenSky Support PO Box 3000 Boulder CO 80307-3000 opensky@ucar.edu http://opensky.ucar.edu/ homepage pointOfContact 2025-12-25T06:30:47.528805 ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded Data ISO 19115-2:2009(E) https://n2t.org/ark:/85065/d7gb27gv https://doi.org/10.26023/30T9-FZ21-4G04 https Related Dataset #1 HIPPO-2 Multiple Enclosure Device for Unfractionated Sampling of Air (MEDUSA) Flask Data. Version 2.0 https://doi.org/10.26023/4NM6-3MPG-WC14 https Related Dataset #2 HIPPO-1 Multiple Enclosure Device for Unfractionated Sampling of Air (MEDUSA) Kernel Data. Version 2.0 https://doi.org/10.26023/AWHD-19RV-GC14 https Related Dataset #3 START-08 Multiple Enclosure Device for Unfractionated Sampling of Air (MEDUSA) Flask Data. Version 1.0 https://doi.org/10.26023/CS11-P31Q-V713 https Related Dataset #4 START-08 Multiple Enclosure Device for Unfractionated Sampling of Air (MEDUSA) Kernel Data. Version 1.0 https://doi.org/10.26023/FF65-2RZM-ZB00 https Related Dataset #5 HIPPO-4 Multiple Enclosure Device for Unfractionated Sampling of Air (MEDUSA) Kernel Data. Version 2.0 https://doi.org/10.26023/GA02-K0FR-C10M https Related Dataset #6 HIPPO-3 Multiple Enclosure Device for Unfractionated Sampling of Air (MEDUSA) Kernel Data. Version 2.0 https://doi.org/10.26023/J0VT-J67P-330R https Related Dataset #7 HIPPO-1 Multiple Enclosure Device for Unfractionated Sampling of Air (MEDUSA) Flask Data. Version 2.0 https://doi.org/10.26023/MYW6-DQQ6-PZ0R https Related Dataset #8 HIPPO-3 Multiple Enclosure Device for Unfractionated Sampling of Air (MEDUSA) Flask Data. Version 2.0 https://doi.org/10.26023/P4PE-KKYS-FZ07 https Related Dataset #9 HIPPO-2 Multiple Enclosure Device for Unfractionated Sampling of Air (MEDUSA) Kernel Data. Version 2.0 https://doi.org/10.26023/PPR2-97CQ-N106 https Related Dataset #10 ARISTO-2015 Airborne Oxygen Instrument. Version 1.0 https://doi.org/10.26023/R8JN-Z3TG-2E0N https Related Dataset #11 HIPPO-5 Multiple Enclosure Device for Unfractionated Sampling of Air (MEDUSA) Flask Data. Version 2.0 https://doi.org/10.26023/X9KY-CK34-VR10 https Related Dataset #12 HIPPO-5 Multiple Enclosure Device for Unfractionated Sampling of Air (MEDUSA) Kernel Data. Version 2.0 https://doi.org/10.26023/XQW5-YHPP-XG0M https Related Dataset #13 HIPPO-4 Multiple Enclosure Device for Unfractionated Sampling of Air (MEDUSA) Flask Data. Version 2.0 https://doi.org/10.3334/CDIAC/HIPPO_010 https Related Dataset #14 HIPPO Merged 10-Second Meteorology, Atmospheric Chemistry, and Aerosol Data. Version 1.0 https://doi.org/10.3334/CDIAC/HIPPO_014 https Related Dataset #15 HIPPO MEDUSA Flask Sample Trace Gas And Isotope Data. Version 1.0 https://doi.org/10.3334/ORNLDAAC/1581 https Related Dataset #16 ATom: Merged Atmospheric Chemistry, Trace Gases, and Aerosols https://doi.org/10.3334/ORNLDAAC/1880 https Related Dataset #17 ATom: L2 In Situ Measurements from the NCAR Airborne Oxygen Instrument (AO2), V2 https://doi.org/10.3334/ORNLDAAC/1881 https Related Dataset #18 ATom: L2 Trace Gas and Isotope Measurements from Medusa Whole Air Sampler, Version 2 https://doi.org/10.5065/D61834TJ https Related Dataset #19 Merged Selected GV Low Rate Flight-Level and Instrument Data and Interpolated GFS Analysis Variables. Version 1.0 https://doi.org/10.5065/D65Q4TF0 https Related Dataset #20 HIPPO-2 Airborne Oxygen Instrument. Version 2.0 https://doi.org/10.5065/D679431D https Related Dataset #21 HIPPO-4 Airborne Oxygen Instrument. Version 2.0 https://doi.org/10.5065/D67H1GXJ https Related Dataset #22 HIPPO-3 Airborne Oxygen Instrument. Version 2.0 https://doi.org/10.5065/D6DJ5CZ5 https Related Dataset #23 START-08 Airborne Oxygen Instrument. Version 2.0 https://doi.org/10.5065/D6H130FW https Related Dataset #24 ORCAS Medusa Flask Sampler Flask Data. Version 2.0 https://doi.org/10.5065/D6J38QVV https Related Dataset #25 HIPPO-1 Airborne Oxygen Instrument. Version 2.0 https://doi.org/10.5065/D6N29VC6 https Related Dataset #26 ORCAS Airborne Oxygen Instrument. Version 2.0 https://doi.org/10.5065/D6SB445X https Related Dataset #27 ORCAS Merge Products. Version 1.0 https://doi.org/10.5065/D6WW7G0D https Related Dataset #28 HIPPO-5 Airborne Oxygen Instrument. Version 2.0 https://doi.org/10.5065/D6DR2SJP https Related PhysicalObject #1 NSF/NCAR GV HIAPER Aircraft https://doi.org/10.5065/D6WM1BG0 https Related PhysicalObject #2 NSF/NCAR Hercules C130 Aircraft Airborne measurements of oxygen concentration from the surface to the lower stratosphere and pole to pole 2021-04-01T00:00:00Z publication https://n2t.org/ark:/85065/d7gb27gv https://doi.org/10.5194/amt-14-2543-2021 Stephens, Britton author Morgan, E. J. author Bent, J. D. author Keeling, R. F. author Watt, Andrew S. author Shertz, Stephen R. author Daube, B. C. author UCAR/NCAR - Library publisher We have developed in situ and flask sampling systems for airborne measurements of variations in the O-2/N-2 ratio at the part per million level. We have deployed these instruments on a series of aircraft campaigns to measure the distribution of atmospheric O-2 from 0-14 km and 87 degrees N to 86 degrees S throughout the seasonal cycle. The National Center for Atmospheric Research (NCAR) airborne oxygen instrument (AO(2)) uses a vacuum ultraviolet (VUV) absorption detector for O-2 and also includes an infrared CO2 sensor. The VUV detector has a precision in 5 s of +/- 1:25 per meg (1 sigma) delta(O-2/N-2), but thermal fractionation and motion effects increase this to +/- 2:5-4.0 per meg when sampling ambient air in flight. The NCAR/Scripps airborne flask sampler (Medusa) collects 32 cryogenically dried air samples per flight under actively controlled flow and pressure conditions. For in situ or flask O-2 measurements, fractionation and surface effects can be important at the required high levels of relative precision. We describe our sampling and measurement techniques and efforts to reduce potential biases. We also present a selection of observational results highlighting the individual and combined instrument performance. These include vertical profiles, O-2 : CO2 correlations, and latitudinal cross sections reflecting the distinct influences of terrestrial photosynthesis, air-sea gas exchange, burning of various fuels, and stratospheric dynamics. When present, we have corrected the flask delta(O-2/N-2) measurements for fractionation during sampling or analysis with the use of the concurrent delta(Ar/N-2) measurements. We have also corrected the in situ delta(O-2 /N-2) measurements for inlet fractionation and hu- midity effects by comparison to the corrected flask values. A comparison of Ar/N-2-corrected Medusa flask delta(O-2/N-2) measurements to regional Scripps O-2 Program station observations shows no systematic biases over 10 recent campaigns (+0 :2 +/- 8 :2 per meg, mean and standard deviation, n = 86). For AO2, after resolving sample drying and inlet fractionation biases previously on the order of 10-100 per meg, independent AO2 delta(O-2/N-2) measurements over six more recent campaigns differ from coincident Medusa flask measurements by -0:3 +/- 7:2 per meg (mean and standard deviation, n = 1361) with campaign-specific means ranging from -5 to +5 per meg. UCAR/NCAR - Library OpenSky Support PO Box 3000 Boulder CO 80307-3000 opensky@ucar.edu http://opensky.ucar.edu/ homepage pointOfContact PDF Text theme Resource Type 2016-01-01T00:00:00Z publication Copyright author(s). This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License. None eng geoscientificInformation