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    • Earth System Research Laboratory Carbon Cycle and Greenhouse Gases Group Continuous Insitu Measurements of CO2, CH4, and CO at Global Background Sites, 1973-Present

    Metadata Updated: September 19, 2023

    The Global Greenhouse Gas Reference Network for the Carbon Cycle and Greenhouse Gases (CCGG) Group is part of NOAA'S Earth System Research Laboratory (ESRL) in Boulder, CO. The Reference Network measures the atmospheric distribution and trends of the three main long-term drivers of climate change, carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O), as well as carbon monoxide (CO) which is an important indicator of air pollution. The Reference Network measurement program includes continuous in-situ measurements at 4 baseline observatories (global background sites) and 8 tall towers, as well as flask-air samples collected by volunteers at over 50 additional regional background sites and from small aircraft. The air samples are returned to ESRL for analysis where measurements of about 55 trace gases are done. NOAA's Global Greenhouse Gas Reference Network maintains the World Meteorological Organization international calibration scales for CO2, CH4, CO, N2O, and SF6 in air. The measurements of the Global Greenhouse Gas Reference Network serve as a comparison with measurements made by many other international laboratories, and with regional studies. They are widely used in studies inferring space-time patterns of emissions and removals of greenhouse gases that are optimally consistent with the atmospheric observations. They serve as an early warning for climate "surprises". The measurements are also helpful for the ongoing evaluation of remote sensing technologies.

    Observatory Measurements: NOAA/ESRL/GMD operates four staffed atmospheric baseline observatories from which numerous measurements of greenhouse gases are conducted. These baseline observatories, also known as global background sites, are located in Barrow, Alaska; Mauna Loa, Hawaii; American Samoa; and South Pole, Antarctica. The measured data are baseline levels, trends, and causes of variability of atmospheric gases that have the potential to affect global climate. These observatories were established in order to provide a sampling of the most remote air on the planet so that the true "background atmosphere" could be monitored. GMD first began continuous in-situ measurements of CO2 at these observatories in 1973, and added CH4 and CO measurements in the 1980's. The ongoing data set is contingent upon the baseline observatories that are still in use going forward.

    A subset of Observatory Measurements for only carbon dioxide (CO2) taken from Observatories is archived separately with digital object identifiers (DOIs) for each of the four observation stations listed above. The observations run from 1973 through the end of 2016. The main portion of this agreement is for the enhanced "version" of the more encompassing dataset for all of the different types of observation platforms and gases.

    Through the Big Earth Data Initiative (BEDI), ESRL/GMD has taken their data collection and converted files into NetCDF-4, a self-describing format.

    Access & Use Information

    License: No license information was provided. If this work was prepared by an officer or employee of the United States government as part of that person's official duties it is considered a U.S. Government Work.

    Downloads & Resources

    Dates

    Metadata Date June 23, 2023
    Metadata Created Date October 28, 2022
    Metadata Updated Date September 19, 2023
    Reference Date(s) 2017-10 (publication), January 1, 1973 (creation)
    Frequency Of Update annually

    Metadata Source

    Harvested from ncdc

    Other Data Resources

    Graphic Preview

    Barrow, Alaska Baseline Observatory

    Additional Metadata

    Resource Type Dataset
    Metadata Date June 23, 2023
    Metadata Created Date October 28, 2022
    Metadata Updated Date September 19, 2023
    Reference Date(s) 2017-10 (publication), January 1, 1973 (creation)
    Responsible Party DOC/NOAA/ESRL/GMD > Global Monitoring Division, Earth System Research Laboratory, NOAA, U.S. Department of Commerce (Point of Contact); NOAA National Centers for Environmental Information (Point of Contact)
    Contact Email
    Guid gov.noaa.ncdc:C01545
    Access Constraints Cite as: E. Dlugokencky, K. Thoning, A. Crotwell, P. Novelli, and NOAA ESRL (2017): Earth System Research Laboratory Carbon Cycle and Greenhouse Gases Group Continuous Insitu Measurements of CO2, CH4, and CO at Global Background Sites, 1973-Present, Version 1. [indicate subset used]. NOAA National Centers for Environmental Information. DOI: 10.7289/V5HD7SX5 [access date]., The information contained herein is provided as a public service, with the understanding that the NOAA/ESRL Global Monitoring Divison makes no warranties, either expressed or implied, concerning the accuracy, completeness, reliability, or suitability of the information., 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., 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.
    Bbox East Long 180.0
    Bbox North Lat 90.0
    Bbox South Lat -90.0
    Bbox West Long -180.0
    Coupled Resource
    Frequency Of Update annually
    Graphic Preview Description Barrow, Alaska Baseline Observatory
    Graphic Preview File https://www.ncei.noaa.gov/pub/data/metadata/images/C01545.jpg
    Graphic Preview Type JPEG
    Harvest Object Id d96ac28e-12a9-439c-83a1-4fefbb50c377
    Harvest Source Id 2cb3ef77-1683-4c2a-9119-dc65e50917c6
    Harvest Source Title ncdc
    Licence
    Lineage Raw data are transferred from station computers back to NOAA/ESRL in Boulder, CO. Known corrections to the data are applied. Once data are analyzed the data are compiled into standard NetCDF files at ESRL/GMD and are archived at the NOAA National Centers for Environmental Information (NCEI).
    Metadata Language eng; USA
    Metadata Type geospatial
    Old Spatial {"type": "Polygon", "coordinates": [[[-180.0, -90.0], [180.0, -90.0], [180.0, 90.0], [-180.0, 90.0], [-180.0, -90.0]]]}
    Progress onGoing
    Spatial Data Service Type
    Spatial Reference System
    Spatial Harvester True
    Temporal Extent Begin 1973-01-01

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