Carbon dioxide fluxes from an urban area in Beijing

Abstract A better understanding of urban carbon dioxide (CO2) emissions is important for quantifying urban contributions to the global carbon budget. From January to December 2008, CO2 fluxes were measured, by eddy covariance at 47 m above ground on a meteorological tower in a high-density residential area in Beijing. The results showed that the urban surface was a net source of CO2 in the atmosphere. Diurnal flux patterns were similar to those previously observed in other cities and were largely influenced by traffic volume. Carbon uptake by both urban vegetation during the growing season and the reduction of fuel consumption for domestic heating resulted in less-positive daily fluxes in the summer. The average daily flux measured in the summer was 0.48 mg m− 2 s− 1, which was 82%, 35% and 36% lower than those in the winter, spring and autumn, respectively. The reduction of vehicles on the road during the 29th Olympic and Paralympic Games had a significant impact on CO2 flux. The flux of 0.40 mg m− 2 s− 1 for September 2008 was approximately 0.17 mg m− 2 s− 1 lower than the flux for September 2007. Annual CO2 emissions from the study site were estimated at 20.6 kg CO2 m− 2 y− 1, considerably higher than yearly emissions obtained from other urban and suburban landscapes.

[1]  M. Kanda,et al.  Seasonal and Diurnal Fluxes of Radiation, Heat, Water Vapor, and Carbon Dioxide over a Suburban Area , 2004 .

[2]  Lasse Møller-Jensen,et al.  Towards a spatial CO2 budget of a metropolitan region based on textural image classification and flux measurements , 2003 .

[3]  E. Parlow,et al.  CO2 fluxes and concentrations over an urban surface in Cairo/Egypt , 2009 .

[4]  Hal Westberg,et al.  Measurements of CO2 fluxes from the Mexico City urban landscape , 2005 .

[5]  D. Steyn,et al.  Diurnal variations of boundary-layer carbon dioxide in a coastal city—Observations and comparison with model results , 1997 .

[6]  S. Dhakal Urban energy use and carbon emissions from cities in China and policy implications , 2009 .

[7]  Thomas Foken,et al.  Documentation and Instruction Manual of the Eddy-Covariance Software Package TK3 (update) , 2011 .

[8]  B. Lamb,et al.  Eddy covariance flux measurements of pollutant gases in urban Mexico City , 2009 .

[9]  Matthias Roth,et al.  Cities as Net Sources of CO 2 : Review of Atmospheric CO2 Exchange in Urban Environments Measured by Eddy Covariance Technique , 2010 .

[10]  J. Wilczak,et al.  Sonic Anemometer Tilt Correction Algorithms , 2001 .

[11]  C. Grimmond,et al.  Five years of carbon dioxide fluxes measurements in a highly vegetated suburban area , 2011 .

[12]  Włodzimierz Pawlak,et al.  Carbon dioxide flux in the centre of Łódź, Poland—analysis of a 2‐year eddy covariance measurement data set , 2011 .

[13]  David Fowler,et al.  Micrometeorological measurements of the urban heat budget and CO2 emissions on a city scale. , 2002, Environmental science & technology.

[14]  C. J. Moore Frequency response corrections for eddy correlation systems , 1986 .

[15]  Andres Schmidt,et al.  Gap Filling and Quality Assessment of CO2 and Water Vapour Fluxes above an Urban Area with Radial Basis Function Neural Networks , 2008 .

[16]  Wu Pei-lin STUDY ON CULTIVATED LAND LOSS AND ITS DRIVING FORCES IN BEIJING 1981-2001 , 2004 .

[17]  Christopher M. Bishop,et al.  Neural networks for pattern recognition , 1995 .

[18]  Thomas Foken,et al.  Quality control of CarboEurope flux data – Part 2: Inter-comparison of eddy-covariance software , 2007 .

[19]  Alessandro Matese,et al.  Carbon Dioxide Emissions of the City Center of Firenze, Italy: Measurement, Evaluation, and Source Partitioning , 2009 .

[20]  Thomas Foken,et al.  Post-Field Data Quality Control , 2004 .

[21]  Wilhelm Kuttler,et al.  Carbon dioxide fluxes over an urban park area , 2010 .

[22]  E. K. Webb,et al.  Correction of flux measurements for density effects due to heat and water vapour transfer , 1980 .

[23]  Timothy R. Oke,et al.  Flux and turbulence measurements at a densely built‐up site in Marseille: Heat, mass (water and carbon dioxide), and momentum , 2004 .

[24]  Jason Beringer,et al.  Characteristics influencing the variability of urban CO2 fluxes in Melbourne, Australia , 2007 .

[25]  G. Pyle,et al.  Toxicity of uranium mine receiving waters to early life stage fathead minnows (Pimephales promelas) in the laboratory. , 2002, Environmental pollution.

[26]  T. Peterson,et al.  An integrated approach to improving fossil fuel emissions scenarios with urban ecosystem studies , 2009 .

[27]  O. Bergeron,et al.  CO2 sources and sinks in urban and suburban areas of a northern mid-latitude city , 2011 .

[28]  T. Foken,et al.  Tools for quality assessment of surface-based flux measurements , 1996 .

[29]  E. Nemitz,et al.  Controls of carbon dioxide concentrations and fluxes above central London , 2010 .

[30]  G. Katul,et al.  An approximate analytical model for footprint estimation of scalar fluxes in thermally stratified atmospheric flows , 2000 .

[31]  Yuesi Wang,et al.  Trend, seasonal and diurnal variations of atmospheric CO2 in Beijing , 2002 .

[32]  Change of NO2 column density over Beijing from satellite measurement during the Beijing 2008 Olympic Games , 2010 .

[33]  D. Nowak,et al.  Local-scale fluxes of carbon dioxide in urban environments: methodological challenges and results from Chicago. , 2002, Environmental pollution.