Carlo Erba until October 2004
Varian from November 2004 onwards
Time Zone
UTC
Data Period
1983-01-01 - 2009-01-01
Data Type
hourly, daily, monthly
Parameter detail
Other Descriptions for Sampling and Analyses
Colum : 1/4 inch molecular sieve colum
Oven temperature : 70 °C
FID temperature : 150 °C
The height of the air intake is 260 m above sea level from the top of a 30 m high mast.
Two freezing units (-4 and -45 °C respectively) are used in series to dry the ambient air prior to analysis.
The data have been recorded at 15 min intervals (96 samples per day) and mixing ratios stored as hourly means (1983 till 1999). From mid-99 onwards, the 15-min intervals have been used to create half-hourly means. These in turn form the basis for the daily and monthly means.
The NOAA CMDL calibration scale is used for all reported data.
Scientific Aim
Observation of long-term CH4 trends in maritime air representative of the southern hemispheric mid-latitudes. Research related to baseline CH4 levels and deducing CH4 sources and sinks.
Supporting Contributor(s)
Last update
2010-02-12
Situation
ongoing
This site is maintained by the Japan Meteorological Agency
in cooperation with the World Meteorological Organization
(Created : 2001/07/02 Modified : 2010/07/31)
WMO World Data Centre for Greenhouse Gases
c/o Japan Meteorological Agency
1-3-4, Otemachi, Chiyoda-ku
Tokyo 100-8122, Japan
WDCGG Data Submission and Dissemination Guide (PDF 1.2Mbyte)
WDCGG leaflet (PDF 2.7MByte, July 2008)
