Products

Urban Heat and CO2 Fluxes

The Eddy Covariance method uses the turbulent transport theory in the surface layer of the atmosphere, and estimates gas and energy fluxes from the covariance between vertical wind speed and the gas concentration and temperature at a measured height above the surface. With eddy covariance, the exchange of various gases and energy between the atmosphere and the underlying surface can be measured. The installed systems in Heraklion measure latent and sensible heat fluxes, as well as CO2 fluxes. Τhe measurements are representative of a wide area around the sensors (footprint) that are estimated to cover a significant part of the surrounded area.

As of 2023, both flux towers have become integral parts of the ICOS (Integrated Carbon Observation System) flux towers network. This integration underscores the exceptional quality of measurements and the utilization of cutting-edge techniques in the acquisition of data.

The Eddy Covariance system, at Heraklion city centre, is equipped with the IRGASON Integrated CO2 / H2O Open-Path Gas Analyser and a 3D Sonic Anemometer (Campbell Scientific, Inc, Utah, USA). It is installed on the roof of a high building in the center of Heraklion (Kornarou Square) since October 2016. The sensor is mounted on a 10 meter telescopic mast in order to reach the appropriate height (27 m) over the urban canopy layer and measure a blended, spatially averaged signal. The system is also equipped with a CNR1 Net Radiometer (Kipp & Zonen B.V. Delft) to measure incoming and outgoing shortwave and longwave radiation.

The Eddy Covariance system, at Mastambas, is equipped with the IRGASON Integrated CO2 / H2O Open-Path Gas Analyser and a 3D Sonic Anemometer (Campbell Scientific, Inc, Utah, USA). It is installed on the roof of a public elementary school since April 2021. The sensor is mounted on a 17 meter tower in order to reach the appropriate height (24 m) over the urban canopy layer and measure a blended, spatially averaged signal. The system is also equipped with a CNR4 Net Radiometer (Kipp & Zonen B.V. Delft) to measure incoming and outgoing shortwave and longwave radiation and an air temperature and relative humidity probe (Rotronic).