Fog Deposition Measurements with the Eddy Covariance Method

The eddy covariance method is considered the only direct flux measurement method. Its application for fog deposition measurements is relatively new and has a high potential to allow the accurate determination of nutrient and trace element deposition due to fog droplet interception by vegetation canopies. Based on experiences gained at an agricultural site on the Swiss Plateau and a mountainous coniferous forest site in Germany we assessed the quality of our data. The accuracy of turbulent liquid water flux measured over a 30 minute period was found to be±0.63 mg m−2 s−1. The accuracy of average liquid water content was found to be 0.14 mg m−3. However, the high statistical noise level reduces the reliability of single short-term measurements and the measured variances of liquid water content. Nevertheless, the quality of the eddy covariance measurements can be considered sufficient for obtaining reliable data on fog interception or occult deposition.