Abstract
Time series analysis on the noise component of CO2 concentration data, measured by a single cell infra-red gas analyzer was conducted. The analysis was performed to examine whether there is any periodic noise in automatically recorded CO2 assimilation data. Two methods were performed for testing the randomness, turning point analysis and phase length analysis. Autocorrelation functions (ACF) and partial autocorrelation functions (PACF) were also computed and inspected. All results were consistent and there was no evidence that indicates the presence of time series noise.