A strategy for quality and uncertainty assessment of long-term eddy-covariance measurements

► A comprehensive quality assessment strategy for long-term eddy-covariance measurement is developed. ► Fundamentally based tests and algorithms are applied. ► This strategy comprises tests on high-frequency data, tests on fluxes and quantification of uncertainty. ► Its robustness and effectiveness is demonstrated for five test data sets. ► The resulting data quality assessment parameters are compared with alternative approaches.