Turbulent sensible heat flux in ?ód?, Central Poland, obtained from scintillometer and eddy covariance measurements

Abstract

Although there are many reports of scintillometer measurements in natural environments, there are few studies concerning the application of scintillometry in urban areas. The main aim of this paper is to present the results of turbulent sensible heat flux (H) measurements with a large aperture scintillometer (LAS) in ?ód?, Central Poland, conducted during the period September 2009?May 2012. The scintillometer data (HLAS) were compared with the results from two eddy covariance towers (HEC) located in the eastern and western parts of the old city core. HLAS was computed with the free and mix convection assumptions. Overall, HLAS and HEC compare well to each other (R2 higher than 0.84). Large discrepancies were found when characteristics of the source areas differed between LAS and EC, in particular for the western EC station under southern, southwestern and to some extent western inflow conditions. The diurnal cycle of H peaks in June but is smaller by the middle of the summer, which was relatively wet in 2010 and 2011. The good performance of LAS even in winter demonstrated its applicability for long-term monitoring of H in urban areas.

Keywords

• eddy covariance
• scintillometer
• sensible heat flux
• urban climate