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 Organization

NO 53
Acronym NIES
Name National Institute for Environmental Studies
Address 1
Address 2 National Institute for Environmental Studies
Address 3 16-2 Onogawa, Tsukuba 305-8506, Japan
Country/Territory Japan
Website https://www.nies.go.jp/index-e.html

 Contact(s)

Name Yasunori TOHJIMA
Prefix Dr.
Email tohjima@nies.go.jp
Organization No 53
Organization acronym NIES
Organization name National Institute for Environmental Studies
Organization country/territory Japan
Address 1
Address 2 National Institute for Environmental Studies
Address 3 16-2, Onogawa, Tsukuba-shi, Ibaraki 305-8506, Japan
Country/territory Japan
Tel
Fax
Last updated date 2023-06-28


 Monitoring background conditions, and the influence of air pollution
 UTC
 ppb
 9999-12-31 00:00:00 - 9999-12-31 23:59:59: NIES94
 9999-12-31 00:00:00 - 9999-12-31 23:59:59: Hewlett Packard 5890 II, Agilent GC 7890 etc.(Gas chromatography (FID))
 9999-12-31 00:00:00 - 9999-12-31 23:59:59: 51.5 (m)
 10 minutes
 NIES Primary standard gases are gravimetrically prepared CH4-in-air mixtures.
From July 1995 to December 1999, the basic GC cycle was 28 injections of the three working standards, each injected twice for each GC analysis, followed by 22 air samples.
Since December 1999, the basic GC cycle has been 12 injections of 3 working standards followed by 9 air samples.
CH4 concentrations of air samples are calculated with calibration curves, which are determined from the two sets of measurements of the working standard gases, measured just before and after the set of air samples. The calibration curve is expressed as a function of peak height (h) and time (t) as follows: y=a+bh+ct, where constant a, b, and c were determined by least square fiitting. The mole fraction is determined from this fitting curve. The working standard gases are calibrated against primary standard gases at NIES before and after their use. The CH4 mole fractions are reported in NIES 94 scale, which is related to the WMO CH4 X2004A according to NIES94=WMO+5ppb.
 Every chromatogram from the instrument is collected via the data acquisition system and stored as raw data, The data acquisition system also analyze the CH4 peaks and sotred peak informations (peak height, area, and so on). CH4 observations are checked remotly via internet by an operator every day.
 [Hourly] Hourly data are taken from the arithmetic mean of observed data for one hour after the irregular and evident error data are rejected.
 [Daily] Daily data are taken from the arithmetic mean of hourly data.
 [Monthly] Monthly data are taken from the arithmetic mean of daily data.
 There is no orginal data quality flags.
 Operational/Reporting
 The height of the intake is 51 meters above ground level (100 meters above mean sea-level). The air samples are dried first by a Nafion® tube dryer and then by a cold trap (-40 °C).
The interval between air sample measurements is 15 minutes for the period from July 1995 to December 1999, and 10 minutes from December 1999.
Study of long-term trends in the level of atmospheric CH4, as one of the baseline monitoring stations for the global environmental research and the policy-making communities.
 Wind direction:
 Wind speed:
 Relative humidity:
 Precipitation amount:
 Air pressure:
 Air temperature:
 Dew point temperature:
 Sea water temperature:
 Sea surface water temperature:
 Sea water salinity:
 Sea surface water salinity:
Meteorological data may remain as first provided, even when greenhouse gas data are updated.
 

 DOI Metadata

DOI
ch4_coi_surface-insitu_53_9999-9999_hourly.nc 10.17595/20160901.004
ch4_coi_surface-insitu_53_9999-9999_hourly.txt 10.17595/20160901.004
ch4_coi_surface-insitu_53_9999-9999_daily.nc 10.17595/20160901.004
ch4_coi_surface-insitu_53_9999-9999_daily.txt 10.17595/20160901.004
ch4_coi_surface-insitu_53_9999-9999_monthly.nc 10.17595/20160901.004
ch4_coi_surface-insitu_53_9999-9999_monthly.txt 10.17595/20160901.004
For more information, please refer: doi.org/10.17595/20160901.004

 Related information

Format Text (WDCGG Data Format Table, WDCGG Meteorological Data Format Table), NetCDF
Relation List (Is Part Of) All CH4 data contributed to WDCGG by GAW stations and mobiles by 2023-09-13
All CH4 data contributed to WDCGG by GAW stations and mobiles by 2022-09-07
All CH4 data contributed to WDCGG by GAW stations and mobiles by 2021-08-27
All CH4 data contributed to WDCGG by GAW stations and mobiles by 2020-09-28
All CH4 data contributed to WDCGG by GAW stations and mobiles by 2019-09-19
All CH4 data contributed to WDCGG by GAW stations and mobiles by 2018-10-25
Geolocation Point
Latitude (north: +; south: -) 43.16028
Longitude (east: +; west: -) 145.49739

 GAW Data Policy

"For Scientific purposes, access to these data is unlimited and provided without charge. By their use you accept that an offer of co-authorship will be made through personal contact with the data providers or owners whenever substantial use is made of their data. In all cases, an acknowledgement must be made to the data providers or owners and to the data centre when these data are used within a publication."

 Citation format

This format is an example of the WDCGG standard citation.
Please follow the citation format which the data providers or owners indicate.
Yasunori TOHJIMA (NIES), Atmospheric CH4 at Cape Ochiishi by National Institute for Environmental Studies , dataset published as CH4_COI_ surface-insitu_NIES_data1 at WDCGG, ver. 2023-07-07-2213 (Reference date*: YYYY/MM/DD)

* As the reference date, please indicate the date you downloaded the files.

 Reference(s)

1  Tohjima et al. (2002), Analysis and presentation of in situ atmospheric methane measurements from Cape Ochi-ishi and Hateruma Island, J. Geophys. Res., 107, 4148, DOI:10.1029/2001JD001003.