Variation of CO 2 mole fraction in the lower free troposphere, in the boundary layer and at the surface

Abstract. Eight years of occasional flask air sampling and 3 years of frequent in situ measurements of carbon dioxide (CO2) vertical profiles on board of a small aircraft, over a tall tower greenhouse gases monitoring site in Hungary are used for the analysis of the variations of vertical profile of CO2 mole fraction. Using the airborne vertical profiles and the measurements along the 115 m tall tower it is shown that the measurements at the top of the tower estimate the mean boundary layer CO2 mole fraction during the mid-afternoon fairly well, with an underestimation of 0.27–0.85 μmol mol−1 in summer, and an overestimation of 0.66–1.83 μmol mol−1 in winter. The seasonal cycle of CO2 mole fraction is damped with elevation. While the amplitude of the seasonal cycle is 28.5 μmol mol−1 at 10 m above the ground, it is only 10.7 μmol mol−1 in the layer of 2500–3000 m corresponding to the lower free atmosphere above the well-mixed boundary layer. The maximum mole fraction in the layer of 2500–3000 m can be observed around 25 March on average, two weeks ahead of that of the marine boundary layer reference (GLOBALVIEW). By contrast, close to the ground, the maximum CO2 mole fraction is observed late December, early January. The specific seasonal behavior is attributed to the climatology of vertical mixing of the atmosphere in the Carpathian Basin.

[1]  George C. Holzworth,et al.  ESTIMATES OF MEAN MAXIMUM MIXING DEPTHS IN THE CONTIGUOUS UNITED STATES , 1964 .

[2]  Measuring system for the long‐term monitoring of biosphere/atmosphere exchange of carbon dioxide , 2001 .

[3]  Petra Seibert,et al.  Review and intercomparison of operational methods for the determination of the mixing height , 2000 .

[4]  Liang Feng,et al.  Evaluating a 3-D transport model of atmospheric CO 2 using ground-based, aircraft, and space-borne data , 2010 .

[5]  X. Rodó,et al.  Atmospheric CO2 in situ measurements: Two examples of Crown Design flights in NE Spain , 2008 .

[6]  Philippe Ciais,et al.  Weak Northern and Strong Tropical Land Carbon Uptake from Vertical Profiles of Atmospheric CO2 , 2007, Science.

[7]  Zoltán Barcza,et al.  History and Sites of Atmospheric Greenhouse Gas Monitoring in Hungary , 2011 .

[8]  K. Davis,et al.  Long-term tall tower carbon dioxide flux monitoring over an area of mixed vegetation , 2005 .

[9]  Y. Niwa,et al.  Carbon balance of South Asia constrained by passenger aircraft CO 2 measurements , 2011 .

[10]  J. Randerson,et al.  An atmospheric perspective on North American carbon dioxide exchange: CarbonTracker , 2007, Proceedings of the National Academy of Sciences.

[11]  D. Fitzjarrald,et al.  Nocturnal vertical CO2 accumulation in two Amazonian ecosystems , 2008 .

[12]  M. Heimann,et al.  Validation of routine continuous airborne CO2 observations near the Bialystok Tall Tower , 2011 .

[13]  T. Machida,et al.  A Lightweight Observation System for Atmospheric Carbon Dioxide Concentration Using a Small Unmanned Aerial Vehicle , 2006 .

[14]  Regional carbon dioxide fluxes from mixing ratio data , 2004 .

[15]  P. Bakwin,et al.  What is the concentration footprint of a tall tower , 2001 .

[16]  S. Wofsy,et al.  Strategies for measurement of atmospheric column means of carbon dioxide from aircraft using discrete sampling , 2003 .

[17]  Shamil Maksyutov,et al.  Atmospheric CO2 inversion validation using vertical profile measurements: Analysis of four independent inversion models , 2011 .

[18]  P. Bakwin,et al.  Measurements of carbon dioxide on a very tall tower , 1995 .

[19]  E. Dlugokencky,et al.  Trends and temporal variations of major greenhouse gases at a rural site in Central Europe , 2008 .

[20]  CP and lepton-number violation in GUT neutrino models with abelian flavour symmetries , 2006, hep-ph/0612292.

[21]  K. Davis,et al.  Regional carbon dioxide fluxes from mixing ratio data , 2004 .

[22]  James B. Abshire,et al.  Calibration of the Total Carbon Column Observing Network using aircraft profile data , 2010 .

[23]  F. Chevallier,et al.  572 Four-dimensional data assimilation of atmospheric CO 2 using AIRS observations , 2022 .

[24]  John C. Lin,et al.  Toward constraining regional‐scale fluxes of CO2 with atmospheric observations over a continent: 1. Observed spatial variability from airborne platforms , 2003 .

[25]  Richard J. Engelen,et al.  Estimating atmospheric CO2 from advanced infrared satellite radiances within an operational four‐dimensional variational (4D‐Var) data assimilation system: Results and validation , 2005 .

[26]  P. Tans,et al.  Atmospheric carbon dioxide at Mauna Loa Observatory: 2. Analysis of the NOAA GMCC data, 1974–1985 , 1989 .

[27]  L. Haszpra Atmospheric greenhouse gases: The Hungarian perspective , 2011 .

[28]  Development of an Atmospheric Carbon Dioxide Standard Gas Saving System and Its Application to a Measurement at a Site in the West Siberian Forest , 2010 .

[29]  Philippe Ciais,et al.  Comparing atmospheric transport models for future regional inversions over Europe - Part 1: mapping the atmospheric CO2 signals , 2006 .

[30]  J. Randerson,et al.  New constraints on Northern Hemisphere growing season net flux , 2007 .

[31]  C. Sweeney,et al.  Regional US carbon sinks from three-dimensional atmospheric CO2 sampling , 2010, Proceedings of the National Academy of Sciences.