Influence of surface inhomogeneity on the formation of turbulent fluxes above the swamp surface

The ability to take into account the thermal inhomogeneity of the surface in atmospheric models is an important task, since a difference in the surface temperature significantly affects the formation of turbulent fluxes. In this paper, an assessment is made of the influence of the thermal inhomogeneity of a wetlands surface on the accuracy of calculating heat fluxes, and a methodology is proposed for taking it into account for the classical Monin-Obukhov similarity theory (MOST). The basis of the work was the data collected during the IAP RAS expedition to the Mukhrino field station from June 11 to June 23, 2022. As part of the expedition, three pulsation measuring complexes were deployed on eddy covariance tower located above wetland micro-landscapes, which differ in the degree of watering: ryam, ridges and swamp. Regular aerial IR surveys of two polygons with a homogeneous and heterogeneous surface were carried out used the DJI Mavic 2 Pro copter and the Flir TAU 2R IR camera. In the course of processing the collected data, a detailed temperature map of the surface of the studied polygons was obtained, footprints for each tower were calculated, and the contribution of the allocated micro-landscapes to the formation of the measured heat flux was estimated. The heat fluxes calculated by the MOST with and without thermal inhomogeneity of the surface. Results were compared with the fluxes obtained by the eddy covariance method. Finally, the estimate was obtained of the effectiveness of the method proposed by the authors for taking into account the thermal inhomogeneity of the surface for modeling turbulent fluxes. This work was supported in part by the Russian Science Foundation grant no. 22-47-04408.