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Greenhouse Gases and Carbon Cycle

Atmospheric carbon dioxide (night-time daily mean mixing ratio) measured at Izaña Observatory since 1984 and derived interannual trend. Superposed to a continuously growing interannual trend (due to anthropogenic emissions), there is a seasonal cycle (net biomass increase in the northern hemisphere spring and summer, and its associated atmospheric carbon dioxide decrease; and net biomass decrease in the northern hemisphere autumn and winter; and its associated atmospheric carbon dioxide increase).

Introduction

News related with this programme

Annual increments of CO2, CH4, N2O, and SF6 measured at Izaña

Infrastructures

IARC Measurement Programmes

Collaborative Measurement Programmes

Some External Links with IARC Contribution

GAW Scientific Audits

Publications

Staff

Introduction

Anthropogenic greenhouse gases increase is the major driver of the present and forthcoming climate change. IARC carries out high quality atmospheric greenhouse gases measurements at Izaña observatory (Global GAW station), following WMO GAW recommendations.

To achieve the high quality required for the measurements, IARC has built measurement systems (hardware based on commercial components; acquisition, control, and raw data processing software done by IARC staff) that work in a non-commercial way (achieving much better accuracy). The measurement systems are continuously calibrated (every 15 minutes or 60 minutes depending on the particular system) using working standards. The working standards are calibrated against the Izaña standards (provided by the WMO GAW Central Calibration Laboratory) every two weeks. Therefore, the measurements are in the WMO scale, and the working standards are traceable to the WMO GAW primary standards.

IARC Greenhouse Gases and Carbon Cycle program deals with the measurement of the main greenhouse gases, but also with carbon monoxide measured with a GC-RGA3 due to: a) the measurement scheme (gas chromatography, and the use of working standards and Izaña standards) is similar to that used with some greenhouse gases, b) carbon monoxide affects the atmospheric burden of methane.


News related with this programme

The state of greehouse gases in the atmosphere based on global observations through 2013

Measurement campaign for obtaining atmospheric vertical profiles of greenhouse gases from an aircraft chartered by the MUSICA and AMISOC projects

17th WMO/IAEA Meeting on Carbon Dioxide, Other Greenhouse Gases, and Related Measurement Techniques (Beijing, China, 10-14 June 2013)

The CO2 has surpassed the threshold of 400 ppm!

The paper titled “A statistical approach to quantify uncertainty in carbon monoxide measurements at the Izaña global GAW station: 2008–2011” has been published in the scientific journal “Atmospheric Measurement Techniques”

NEW PUBLICATION: Quantifying uncertainty in carbon monoxide measurements at the Izaña global GAW station (2008-2011)

Atmospheric Carbon Monoxide measurements time series at Izaña Observatory

Greenhouse gases annual increment at Izaña Atmospheric Observatory during 2011.

The greenhouse gases annual bulletin has been just published by the World Meteorological Organization

16th WMO/IAEA meeting on carbon dioxide, other greenhouse gases, and related measurement techniques (Wellington, New Zealand 25th–28th October 2011)

Update of the product GLOBALVIEW-CO2, and some explanations to understand the Atmospheric Carbon Cycle

Annual increments of CO2, CH4, N2O, and SF6 measured at Izaña

Update of Izaña Carbon Dioxide Time Series (June 1984-March 2011)

The Sulphur Hexafluoride atmospheric series of Izaña (June 2007-December 2010) is published by first time

Update of the Methane atmospheric series of Izaña (June 1984-March 2011)

Series of Atmospheric Nitrous Oxide measured at Izaña (2007-2010)

Update of the Carbon Dioxide and Methane atmospheric series of Izaña (1984-2010)

15th WMO/IAEA Meeting of Experts on CO2 Measurement Techniques (September 7-10, 2009; Jena, Germany)

CH4 in the atmosphere. The updated Izana’s CH4 record (1984-2009)

Izaña’s updated CO2 Series (May 28th, 2009)

 

Annual increments of CO2, CH4, N2O, and SF6 measured at Izaña

The panel with the graphics (click it to see the panel at a larger size) shows the annual increments (in relative percentage, click here to see the graphics of absolute increments) for the greenhouse gases CO2, CH4, N2O, and SF6 measured at Izaña Atmospheric Observatory. In detail, the annual increment for a given year has been obtained computing the difference between the mean of such year and the mean of the previous year, therefore, there is not increment associated to the first year of each measurement series.

The time series with daily data for these gases measured at Izaña can be seen in the following Izaña news: CO2 (news dated on April 5, 2011), CH4 (news dated on March 29, 2011), N2O (news dated on March 21, 2011), and SF6 (news dated on April 5, 2011), additionally to comments about each atmospheric component and series.

The few time intervals in the series with data gaps, have been filled using an estimation obtained from the series themselves: interannual trend (blue line of the corresponding time series) plus a constant in time annual cycle (no plotted in the graphics with the series), both computed applying a Fourier analysis and keeping only the appropriate harmonics (click here to see specialized information about this topic). Due to the fact that this method is not perfect, the first computed annual increment for each series (for example, 1985 for CO2 and CH4) has a very high uncertainty (error), because all these gas measurements were initiated in middle year (in June for CO2, N2O, and SF6; and July for CH4). Additionally, such method can introduce a high uncertainty where the gaps are large. Therefore, the graphics also show the percentage of available measured data used to compute the annual increments, in detail, for each increment, the mean percentage of available data in the two years used to compute such increment is plotted.

Infrastructures

The two general ambient air inlets which provide ambient air for all instruments that analyse it, are 8cm inner diameter (ID) stainless steel pipes, and have a high flow rate. These inlets are situated on top of the building tower; the height above the ground has changed through the years: 13 m (1984-2000), 8 m (2000- May 2005) and 30 m (from June 2005). The measurement systems for greenhouse gases and carbon monoxide are located in two laboratories on the third floor of the Izaña Observatory tower.

 

The central facility which distributes chromatographic gases (nitrogen, hydrogen, synthetic air, argon/methane 95%/5%) is located on the ground floor. At the same floor, there is a system to fill tanks with dried ambient air (operated by AirLiquide Canarias) with the desired slightly modified levels of carbon dioxide, in order to create working standards. This system is similar to the system which NOAA/ESRL/GMD uses to fill standards.

IARC Measurement Programmes

Carbon Dioxide (measured in-situ continuously since 1984 with NDIR analysers)

The main part of the measurement system is a NDIR analyser (Siemens Ultramat 3 from 1984 to 2006; LI-COR Li-7000 from 2007 till present, working simultaneously -in series- with a LI-COR Li-6252 from 2008 till present). Upstream of the NDIR, a cryocool trap is used to reduce the dew point of ambient air to -65 C.

From 1984 to 2006, instrument calibrations are performed using 3 working standards (during 6 minutes each one) every 3 hours (starting at 00:00 UTC every day). From 2006 till present, instrument calibrations are performed using 3 working standards (during 3 minutes each one) every hour (starting at 00:30 UTC every day). The working standards are calibrated against IARC standards, which were provided by WMO GAW CO2 CCL. In detail: a) Before 2000, three levels of station standard gases were used (primary, secondary and working gases). The working gases were calibrated against the secondary gases every 2 weeks. The secondary tanks were calibrated against the station primary tanks every 3 or 4 months. b) After 2000, only two levels of station standard gases are used (primary and working gases). The working tanks are calibrated every 2 weeks against primary tanks.

 

Between calibrations, ambient air is analysed continuously and raw data are stored. Physical data are obtained using the instrument calibrations performed using 3 working standards.

Download pdf with additional information on CO2 measurements

Methane (measured in-situ continuously since 1984 with a GC-FID)

The main part of the measurement system is a gas chromatograph GC-3800 DANI with a flame ionization detector (FID). Upstream of the GC sample loop (10 ml size), a cryocool trap is used to reduce the dew point of ambient air to -45 C. The instrument is calibrated every 30 minutes using a working gas tank (at minutes 15 and 45 every hour). The working gas tank is calibrated every two weeks against the methane Izana standards (provided by WMO GAW CH4 CCL). Four samples are automatically measured every hour: at 00 and 30 minutes the sample is ambient air, at 15 and 45 minutes the sample is working gas. Physical data for each ambient air injection are obtained using the two bracketing instrument calibrations (injections of working gas).

 

 

 

 

 

 

 

 

Nitrous Oxide and Sulphur Hexafluoride (measured in-situ continuously since 2007 with a GC-ECD)

(download pdf with the instrumental description)

Carbon Monoxide (measured in-situ continuously since 1998 with a GC-RGA3)

Collaborative Measurement Programmes

Since 1991, IARC collects weekly ambient air in a pair of flasks for the NOAA/ESRL/GMD CCGG Cooperative Air Sampling Network. NOAA/ESRL/GMD/CCGG analyses in these samples the mixing ratio of carbon dioxide (and its stable isotope ratios), methane, carbon monoxide, hydrogen, nitrous oxide, sulphur hexafluoride, and recently, some more trace gases.

Since 1984, IARC collects carbon dioxide samples (using a sodium hydroxide solution) for the Carbon Cycle Group, Institut für Umweltphysik, University of Heidelberg. They analyse such samples for the radioactive isotope carbon 14.

Some External Links with IARC Contribution

After processing and quality controlling, IARC greenhouse gases data are submitted to the WMO GAW World Data Center for Greenhouse Gases (WDCGG).

Also, IARC contributes to the products GLOBALVIEW-CO2, GLOBALVIEW-CH4 and OBSPACK.

IARC contributes to the computation of CO2 surface fluxes carried out by Max-Planck Institute of Jena.

IARC contributes to the computation of CO2 global distribution that carries out the Japan Meteorological Agency using an inversion model.

GAW Scientific Audits

Methane and Carbon monoxide Audit (EMPA, March 2009) (download pdf)

Nitrous Oxide Audit (Dr Eckhart Scheel, WCC-N2O, November 2008) (download pdf)

Methane and Carbon monoxide Audit (EMPA, December 2004) (download pdf)

Publications


Gomez-Pelaez, A.J., R. Ramos, V. Gomez-Trueba, R. Campo-Hernandez,E. Reyes-Sanchez: "Izaña Global GAW station greenhouse-gas measurement programme. Novelties and developments during October 2011-May 2013" to be published in the GAW report of the "17th WMO/IAEA Meeting on Carbon Dioxide, Other Greenhouse Gases, and Related Measurement Techniques (Beijing, China, June 10-14, 2013)", World Meteorological Organization, 2013 (download pdf).

Gomez-Pelaez, A. J., Ramos, R., Gomez-Trueba, V., Novelli, P. C., and Campo-Hernandez, R.: A statistical approach to quantify uncertainty in carbon monoxide measurements at the Izaña global GAW station: 2008–2011, Atmos. Meas. Tech., 6, 787-799, doi:10.5194/amt-6-787-2013, 2013 (link to the article)

Sepúlveda, E., M. Schneider, F. Hase, O. E. García, A. Gomez-Pelaez, S. Dohe, T. Blumenstock, and J.C. Guerra, Long-term validation of tropospheric column-averaged CH4 mole fractions obtained by mid-infrared ground-based FTIR spectrometry, Atmos. Meas. Tech., 5, 1425-1441, doi:10.5194/amt-5-1425-2012, 2012 ( link to the article)

Chevallier, F., N. M. Deutscher, T. J. Conway, P. Ciais, L. Ciattaglia, S. Dohe, M. Fröhlich, A.J. Gomez-Pelaez, D. Griffith, F. Hase, L. Haszpra, P. Krummel, E. Kyrö, C. Labuschagne, R. Langenfeld, T. Machida, F. Maignan, H. Matsueda, I. Morino, J. Notholt, M. Ramonet, Y. Sawa, M. Schmidt, V. Sherlock, P. Steele, K. Strong, R. Sussmann, P. Wennberg, S. Wofsy, D. Worthy, D. Wunch, M. Zimnoch, Global CO2 fluxes inferred from surface air-sample measurements and from TCCON retrievals of the CO2 total column, Geophysical Research Letters, 38, L24810, doi: 10.1029/2011GL049899, 2011 (link to the article)

Gomez-Pelaez, A.J., R. Ramos, V. Gomez-Trueba, R. Campo-Hernandez, E. Dlugokencky, T. Conway "New improvements in the Izaña (Tenerife, Spain) global GAW station in-situ greenhouse gases measurement program" to be published in the GAW report of the "16th WMO/IAEA Meeting on Carbon Dioxide, Other Greenhouse Gases, and Related Measurement Techniques (Wellington, New Zealand, October 25-28, 2011)", World Meteorological Organization, 2011 (download pdf).

Chevallier, F., P. Ciais, T. J. Conway, T. Aalto, B. E. Anderson, P. Bousquet, E. G. Brunke, L. Ciattaglia, Y. Esaki, M. Fröhlich, A. Gomez, A. J. Gomez-Pelaez, L. Haszpra, P. B. Krummel, R. L. Langenfelds, M. Leuenberger, T. Machida, F. Maignan, H. Matsueda, J. A. Morguí, H. Mukai, T. Nakazawa, P. Peylin, M. Ramonet, L. Rivier, Y. Sawa, M. Schmidt, L. P. Steele, S. A. Vay, A. T. Vermeulen, S. Wofsy, D. Worthy, , CO2 surface fluxes at grid point scale estimated from a global 21 year reanalysis of atmospheric measurements, J. Geophys. Res., 115, D21307, doi:10.1029/2010JD013887, 2010.(link to the paper in JGR website).

Gomez-Pelaez, A.J., R. Ramos, E. Cuevas, V. Gomez-Trueba, 25 years of continuous CO2 and CH4 measurements at Izaña Global GAW mountain station: annual cycles and interannual trends; Proceedings of the “Symposium on Atmospheric Chemistry and Physics at Mountain Sites (ACP Symposium 2010, June 8-10, 2010, Interlaken, Switzerland)”, 157-159, 2010 (download pdf)

Levin, I., T. Naegler, B. Kromer, M. Diehl, R. Francey, A. J. Gomez-Pelaez, L. P. Steele, D. Wagenbach, R. Weller, and D.E. Worthy, Observations and modelling of the global distribution and long-term trend of atmospheric 14CO2, Tellus (2010), 62B, 26–46 (download pdf)

Gomez-Pelaez, A.J., Ramos, R., "Improvements in the Carbon Dioxide and Methane Continuous Measurement Programs at Izaña Global GAW Station (Spain) during 2007-2009", in GAW report (No. 194) of the “15th WMO/IAEA Meeting of Experts on Carbon Dioxide, Other Greenhouse Gases, and Related Tracer Measurement Techniques (Jena, Germany; September 7-10, 2009)”, edited by Willi A. Brand, World Meteorological Organization (TD No. 1553), 133-138, 2011 (download pdf)

Gomez-Pelaez, A.J., Ramos, R., "Installation of a new gas chromatograph at Izaña GAW station (Spain) to measure CH4, N2O, and SF6" in GAW Report (No. 186) of the "14th WMO/IAEA meeting of experts on Carbon dioxide, other greenhouse gases, and related tracers measurement techniques (Helsinki, Finland, 10-13 September 2007)", edited by Tuomas Laurila, World Meteorological Organization (TD No. 1487), 55-59, 2009 (download pdf)

Gomez-Pelaez, A.J., "A brief overview of the theory of flow along GC packed columns and some practical consequences for measuring atmospheric CH4, N2O, and SF6" in GAW Report (No. 186) of the "14th WMO/IAEA meeting of experts on carbon dioxide, other greenhouse gases, and related tracers measurement techniques (Helsinki, Finland, 10-13 September 2007)", edited by Tuomas Laurila, World Meteorological Organization (TD No. 1487), 60-64, 2009 (download pdf)

Patra, P. K., M. Takigawa, K. Ishijima, B.-C. Choi, D. Cunnold, E. J. Dlugokencky, P. Fraser, A. J. Gomez-Pelaez, T.-Y. Goo, J.-S. Kim, P. Krummel, R. Langenfelds, F. Meinhardt, H. Mukai, S. O'Doherty, R. G. Prinn, P. Simmonds, P. Steele, Y. Tohjima, K. Tsuboi, K. Uhse, R. Weiss, D. Worthy and T. Nakazawa, Growth rate, seasonal, synoptic, diurnal variations and budget of methane in lower atmosphere, J. Meteorol. Soc. Jpn., 87(4), 635-663, 2009. (Copyright MSJ). Download pdf.

Gomez-Pelaez, A.J., Ramos, R., Perez-delaPuerta, J., "Methane and carbon dioxide continuous measurements at Izana GAW station (Spain)" in GAW Report (No. 168) of the "13th WMO/IAEA Meeting of Experts on Carbon Dioxide Concentration and Related Tracers Measurement Techniques
(Boulder, Colorado, USA, 19-22 September 2005)", edited by J.B. Miller, World Meteorological Organization (TD No. 1359), 180-184, 2006 (download pdf)

Ripodas, P., Ramos, R., Cuevas, E., Calbet, X., "1984-1999 CO2 time series at Izana (Tenerife). Long range transport effects". Report of the "2 Asamblea Hispano Portuguesa de Geodesia y Geofisica", Lagos, Portugal, 2000, page. 467.

Staff

Angel J. Gomez-Pelaez (Program Leader)

Ramon Ramos-Lopez (partial time dedication to this program)

Ruben del Campo Hernandez (partial time dedication to this program)

Vanessa Gomez-Trueba (AirLiquide Canarias staff)