Surface–atmosphere interactions over complex urban terrain in Helsinki, Finland

Timo Vesala; Leena Järvi; Samuli Launiainen; Andrei Sogachev; Üllar Rannik; Ivan Mammarella; Erkki Siivola; Petri Keronen; Janne Rinne; Anu Riikonen; Eero Nikinmaa

doi:10.1111/j.1600-0889.2007.00312.x

Surface–atmosphere interactions over complex urban terrain in Helsinki, Finland

Tellus B: Chemical and Physical Meteorology

Volume 60 (2008): Issue 2

By: Timo Vesala, Leena Järvi, Samuli Launiainen, Andrei Sogachev, Üllar Rannik, Ivan Mammarella, Erkki Siivola, Petri Keronen, Janne Rinne, Anu Riikonen and Eero Nikinmaa

Open Access

|Jan 2008

Abstract

Long-term measurements of fluxes of sensible heat (H), latent heat (LE) and carbon dioxide (F_c) were made from December 2005 to August 2006 over an urban landscape in Helsinki, Finland using the direct micrometeorological eddy covariance technique. Three distinguished sectors of land-use cover (vegetation, roads and buildings) allowed comparisons of fluxes over different urban surfaces. The normalized standard deviation of wind and scalars as a function of atmospheric stability were typical for rough surfaces, as were turbulence spectra and cospectra. Footprint analysis was performed by a boundary-layer one and half-order closure model allowing for discrimination of surface and canopy sinks/sources and complex topography. Fluxes were analysed as average diurnal courses over winter, spring and summer periods. H exceeded LE reaching 300 W m^-2 over urban and road surfaces in the summer and it was close to 100 W m^-2 in the winter. LE was highest in the summer over vegetation cover attaining 150 W m^-2. The emission rate of CO₂ was high over road sector [20 μmol (m²s)^-1] [Correction added after online publication 16 Oct 2007: 30 μmol changed to 20 μmol] while in the vegetation sector it remained below 5 μmol (m²s)^-1 and at summertime reached even −10 μmol (m²s)^-1 [Correction added after online publication 16 Oct 2007: wording of sentence altered]. Effluxes from soil measured by chambers were 1-3 μmol (m²s)^-1. F_c correlated with traffic density and a background non-vehicle flux was 1 μmol (m²s)-1 [Correction added after online publication 16 Oct 2007: 2 μmol changed to 1 μmol].

References

Aubinet , M. , Berbigier , P. , Bernhofer , Ch. Cescatti , A. , Feigenwinter , C. and co-authors. 2005. Comparing CO2 storage and advection conditions at night at different carboeuroflux sites. Boundary-Layer MeteoroL 116 , 63 – 93 .
Search in Google Scholar Back to article
Aubinet , M. , Grelle , A. , Ibrom , A. , Rannilc , C. , Moncrieff , J. and co-authors. 2000. Estimates of the annual net carbon and water exchange of European forests: the EUROFLUX methodology. Adv. EcoL Res . 30 , 114 – 175 .
Search in Google Scholar Back to article
Baldocchi , D. , Falqe , E. , Gu , L. H. Olson , R. , Hollinger , D. and co-authors. 2001. FLUXNET: A new tol to study the temporal and spatial variability of ecosystem-scale carbon dioxide, water vapour, and energy flux densities. Bull. Amer MeteoroL Soc . 82 , 2415 – 2434 .
Search in Google Scholar Back to article
Burba , G. , Anderson , D. , Liukang , Xu and McDermitt , D . 2006 . Correcting apparent off-season CO2 uptake due to surface heating of an open path gas analyzer: progress report of an ongoing study. Proceedings of 27th Annual Conference of Agricultural and Forest Meteorology , Amer. Met. Soc., San Diego, California, USA, pp. 1 – 13 .
Search in Google Scholar Back to article
Constantin , J. , Grelle , A. , Ibrom , A ., ja Morgenstern, K. 1999. Flux partitioning between understorey and overstorey in a boreal spruce/pine forest determined by the eddy covariance method. Agric. For Meteorol . 98-99, 629 – 643 .
Search in Google Scholar Back to article
De Bruin , H. A. R. , Kohsiek , W. and Van Den Hurk , J. J. M . 1993 . A verification of some methods to determine the fluxes of momentum, sensible heat, and water vapor using standard deviation and structure parameter of scalar meteorological quantities . Boundary-Layer Meteorol . 63 , 231 – 257 .
Search in Google Scholar Back to article
Eugster , W. , Kling , G. , Jonas , T. , McFadden , J. P. , Wiiest , A. and co-authors. 2003. CO2 exchange between air and water in an Arctic Alaskan and midlatitude Swiss lake: importance of convective mixing. J. Geophys. Res. 108(D12), 4362, 10.1029/2002JD002653 . Finnigan, J. 2004. The footprint concenpt in complex terrain. Agric. For MeteoroL. 127 , 117 – 129 .
Open DOI Search in Google Scholar Back to article
Foken , T . 2006 . 50 years of te Monin-Obulchov similarity theory . Boundary-Layer MeteoroL 119 , 431 – 447 .
Search in Google Scholar Back to article
Foken , T. H. , and Wichura , B . 1996 . Tools for quality assessment of surface-based flux measurements . Agric. For MeteoroL 78 , 83 – 105 .
Search in Google Scholar Back to article
Grimmond , C. S. B. , King , T. S. , Cropley , F. D. , Nowak , D. J. and Souch , C . 2002 . Local-scale fluxes of carbon dioxide in urban environments: methodological challenges and results from Chicago . Environ. Pollut . 116 , 243 – 254 .
Search in Google Scholar Back to article
Grimmond , C. S. B. and Oke , T . 1999 . Aerodynamic Properties of Urban Areas Derived from Analysis of Surface Form . J. Appl. Meteorol . 38 , 1262 – 1292 .
Search in Google Scholar Back to article
Grimmond , C. S. B. , Salmond , J. A. , Oke , T. R. , Offerle , B. and Lemonsu , A . 2004 . Flux and turbulence measurements at a dense urban site in Marseille: heat, mass (water, carbon dioxide) and momentum . J. Geophys. Res . 109 ( D24 ), D24101 , 10.1029/2004JDO04936 .
Open DOI Search in Google Scholar Back to article
Kaimal , J. C. and Kristensen , L . 1991 . Time series tapering for short data samples . Boundary-Layer Meteorol . 57 , 187 – 194 .
Search in Google Scholar Back to article
Kolari , R , Kulmala , L. , Tupek , B. , Alm , J. , Han , P. and co-authors. 2005. Photosynthetic production of boreal forest floor vegetation; seasonal and spatial variation. Proceedings of BACCI, NECC and FCoE activities 2005 , Book A, Finnish Association for Aerosol Research, 249 – 254 .
Search in Google Scholar Back to article
Lilleberg , I. and Hellman , T . 2006 . Traffic trends in Helsinki in 2005 (in Finnish) . Helsinki City Planning Department .
Search in Google Scholar Back to article
Markkanen , T. , Rannik , Ü. , Keronen , P. , Suni , T. and Vesala , T. 2001. Eddy covariance fluxes over a boreal Scots pine forest. Boreal Env. Res . 6 , 65 – 78 .
Search in Google Scholar Back to article
Moriwaki , R. and Kanda , M . 2004 . Seasonal and diurnal fluxes of radiation, heat, water vapour, and carbon dioxide over a suburban Area . J. AppL Meteorol . 43 , 1700 – 1710 .
Search in Google Scholar Back to article
Markkanen , T. , Rannik , U. , Marcolla , B. , Cescatti , A. and Vesala , T . 2003 . Footprints and feches for fluxes over forest canopies with varying structure and density . Boundary-Layer Meteorol . 106 , 437 – 459 .
Search in Google Scholar Back to article
Myllynen , M. , Aarnio , P. , Koskentalo , T. and Malldci , M . 2006 . Air Quality in Helsinki Metropolitan Area year in 2005 (in Finnish) . YTV Helsinki Metropolitan Area Council .
Search in Google Scholar Back to article
Mäkeld , K. , Laurilcko , J. and Kanner , H . 2005 . Road traffic exhaust gas emissions in Finland. LIISA 2004 calculation software (in Finnish). Technical Research Centre of Finland , Buildings and Transport , Research Report RTE 2881/05 .
Search in Google Scholar Back to article
Nemitz , E. , Hargreaves , K. J. , McDonald , A. G. , Dorsey , J. R. and Fowler , D . 2002 . Micrometeorological measurements of the urban heat budget and CO2 emissions on a city scale . Environ. Sci. TechnoL 36 , 3139 – 3146 .
Search in Google Scholar Back to article
Rannik , U. , Altimir , N. , Raittila , J. , Suni , T. , Gaman , A. and co-authors. 2002. Fluxes of carbon dioxide and water vapour over Scots pine forest and clearing. Agric. For Meteorol . 111 , 187 – 202 .
Search in Google Scholar Back to article
Roth , M . 2000 . Review of atmospheric turbulence over cities . Quart. J. Roy. Meteorol. Soc . 126 , 941 – 990 .
Search in Google Scholar Back to article
Roth , M. and Oke , T. R . 1995 . Relative efficiencies of turbulent transfer of heat, mass and momentum over a patchy urban surface. J. Atmos. Sci . 52 , 1863 – 1874 .
Search in Google Scholar Back to article
Salmond , J. A. , Oke , T. R. , Grimmond , C. S. B. , Roberts , S. and Offerle , B . 2005 . Venting of heat and carbon dioxide from urban canyons at night . J. AppL Meteorol . 44 , 1180 – 1194 .
Search in Google Scholar Back to article
Schmid , H. P . 1994 . Source areas for scalar and scalar fluxes . Boundary-Layer Meteorol . 67 , 293 – 318 .
Search in Google Scholar Back to article
Schmid , H. P . 2002 . Footprint modeling for vegetation atmosphere exchange studies: a review and perspective . Agric. For. Meteorol . 113 , 159 – 183 .
Search in Google Scholar Back to article
Schuepp , P. H. , Leclerc , M. Y. , MacPherson , J. I. and Desjardins , R. L . 1990 . Footprint prediction of scalar fluxes from analytical solutions of the diffusion equation . Boundary-Layer Meteorol . 50 , 355 – 373 .
Search in Google Scholar Back to article
Soegaard , H. and Moller-Jensen , L . 2003 . Towards a spatial CO2 budget of a metropolitan region based on textural image classification and flux measurements . Remote Sens. Environ . 87 , 283 – 294 .
Search in Google Scholar Back to article
Sogachev , A. Y. and Lloyd , J. J . 2004 . Using a one-and-a-half order closure model of the atmospheric boundary layer for surface flux footprint estimation . Boundary-Layer Meteorol . 112 , 467 – 502 .
Search in Google Scholar Back to article
Sogachev , A. and Panferov , O . 2006 . Modification of two-equation models to account for plant drag . Boundary-Layer Meteorol . 121 , 229 – 266 .
Search in Google Scholar Back to article
Sogachev , A. , Panferov , O. , Gravenhorst , G. and Vesala , T . 2004b . Numerical analysis of flux footprints for different landscapes . Theoretical and Applied Climatology 80 , 169 – 185 .
Search in Google Scholar Back to article
Sogachev , A. , Rannik , U. and Vesala , T . 2004a . On flux footprints over the complex terrain covered by a heterogeneous forest . Agric. For Meteorol . 127 , 143 – 158 .
Search in Google Scholar Back to article
Sogachev , A. , Menzhulin , G. , Heimann , M. and Lloyd , J . 2002 . A simple three-dimensional canopy - planetary boundary layer simulation model for scalar concentrations and fluxes . Tellus 54B ( 5 ), 784 – 819 .
Search in Google Scholar Back to article
Stull , R. B . 1988 . An introduction to boundary-layer meteorology . Kluwer Academic Publishers .
Search in Google Scholar Back to article
Suni , T. , Rinne , J. , Reissell , A. , Altimir , N. , Keronen , P. and co-authors. 2003. Long-term measurements of surface fluxes above a Scot pine forest in Hyytiälä. southern Finland, 1996-2001. Boreal Environ. Res . 8 , 287 – 301 .
Search in Google Scholar Back to article
Vogt , R. , Christensen , A. , Rotach , M. W. , Roth , M. and Satyanarayana , A. N. V . 2003 . Fluxes and profiles of CO2 in the urban roughness sublayer. Preprints, 5th International Conference on Urban Climate , Lodz, Poland, International Association for Urban Climate, 321 – 324 .
Search in Google Scholar Back to article
Vogt , R. , Christensen , A. , Rotach , M. W. , Roth , M. and Satyanarayana , A. N. V . 2006 . Temporal dynamics of CO2 fluxes and profiles over a Central European city . Theor AppL Climatol . 84 , 117 – 126
Search in Google Scholar Back to article
Webb , E. K. , Pearman , G. I. and Leuning , R . 1980 . Correction of flux measurements for density effects due to heat and water vapour transfer . Quart. J. Roy. Meteorol. Soc . 106 , 85 – 100 .
Search in Google Scholar Back to article
Wilczak , J. M. , Oncley , S. P. and Stage , S. A . 2001 . Sonic anemometer Tilt Correction Algorithms . Boundary Layer Meteorol . 99 , 127 – 150 .
Search in Google Scholar Back to article

Articles in this issue

DOI: https://doi.org/10.1111/j.1600-0889.2007.00312.x | Journal eISSN: 1600-0889

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Language: English

Page range: 188 - 199

Submitted on: Dec 1, 2006

Accepted on: Jul 1, 2007

Published on: Jan 1, 2008

Published by: Stockholm University Press

In partnership with: Paradigm Publishing Services

© 2008 Timo Vesala, Leena Järvi, Samuli Launiainen, Andrei Sogachev, Üllar Rannik, Ivan Mammarella, Erkki Siivola, Petri Keronen, Janne Rinne, Anu Riikonen, Eero Nikinmaa, published by Stockholm University Press
This work is licensed under the Creative Commons Attribution 4.0 License.

Volume 60 (2008): Issue 2