An urban flux tower for atmospheric turbulence and trace gas flux studies

 Gunnar W. Schade, C. H. Park I. BoedekerTexas A&M University, College Station, TX

Site Description, I

Site Description, IIland use (+winds)

land cover

Hardy / Elysian Roads

Traffic Counts

Hardy (south bound) Elysian (north bound)

Quitman Road (east/west bound)

How it looks like

Tower Measurement Setup

Tower

PAR pyranometer

net radiation

Sonic

WS/WD aspirated T/RH

N

3/8’’ and 1/4“ OD PFA Tubes

Lag time ≈ 9 s

BaseBuilding

60 m

50 m

40 m

20 m

13 m Relaxed Eddy Accumulation

GC-FID

PC

Wind data (10 Hz)

w

DL

CO2 H2O slow: CO, NOx, O3

EC

gradient

Integral statistics example I

Integral statistics example II

no roughness sub-layer influence

d and z0 distributions

displacement height related to cumulative roughness element parameters

site (in)homogeneities I

site (in)homogeneities II

site (in)homogeneities III

site (in)homogeneities IV

seasonality I

winter

summer

seasonality II

weekday

weekend

VOC flux

VOC flux

Summary Operated from summers 2007 to 2009 Results very similar to previous urban

turbulence research • comfortable that site is well-suited for flux

measurements• flux data is under renewed investigation

Obtained follow-up funding• will commence this summer• expand with particle flux measurements

Acknowledgements

Houston Yellow Cab Texas A&M University startup Texas Air Research Center

Bernhard Rappenglück TCEQ