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Table 2 CO2 fluxes and their uncertainties with different processing procedures

From: Comparative assessment of net CO2 exchange across an urbanization gradient in Korea based on eddy covariance measurements

FC (unit: μmol m2 s1) Mean Std. 25% 50% 75%
Default (double rotation & block averaging only) 8.8 7.3 2.3 7.8 14.4
  1. Data period is 1-month (March 2015) from HU site. Italic indicates the methods applied in this study
Difference with default (EXP-default; unit: μmol m−2 s−1)
Coordinate rotation
 Triple rotation − 0.1 1.5 0.0 0.0 0.1
 Planar fit [24] − 0.8 3.8 − 1.7 − 0.5 0.3
 Planar fit [25] − 1.0 3.9 − 1.9 − 0.6 0.3
Detrending
 Linear detrending − 0.4 3.9 − 1.3 − 0.1 0.4
 Running mean 250 s − 0.7 4.3 − 2.0 − 0.5 0.8
 Exponential running mean 250 s − 0.9 3.8 − 2.0 − 0.6 0.2
Time Lags Compensation
 Covariance maximization 0.0 0.1 0.0 0.0 0.1
 Covariance maximization with default 0.1 0.1 0.0 0.0 0.1
 Automatic time lag Optimization 0.0 0.1 0.0 0.0 0.1
Spike count/removal
 Mauder et al. [26], accepted spikes 1–30% − 0.5 1.4 − 0.3 0.0 0.0
 Vickers and Mahrt [27] (VM97), Max consecutive outliers (MCO) 3 − 0.1 0.2 − 0.1 0.0 0.0
 VM97, MCO 10 − 0.2 0.4 − 0.2 0.0 0.0
 VM97, MCO 30 − 0.3 0.7 − 0.4 − 0.1 0.0
 VM97, MCO 50 − 0.4 0.8 − 0.4 − 0.1 0.0
 VM97, MCO 70 − 0.4 0.8 − 0.5 − 0.1 0.0
Amplitude resolution
 4–7 sigma, number of bins 50–150 0.0 0.1 0.0 0.0 0.1
Dropouts
 Accepted central dropouts 5–20% 0.0 0.1 0.0 0.0 0.1
Absolute limits 0.0 0.1 0.0 0.0 0.1
Skewness & Kurtosis 0.0 0.1 0.0 0.0 0.1
Discontinuities 0.0 0.1 0.0 0.0 0.1
Spectral correction
 Low-frequency range [28] 0.3 0.4 0.1 0.2 0.4
 High-frequency range (HFR) [29] 0.1 0.2 0.0 0.1 0.2
 HFR [30, 31] 0.7 1.0 0.2 0.4 0.8
 HFR [32] 0.2 0.3 0.0 0.1 0.4
 HFR [33] with Horst and Lenschow [34] (HL09): along-wind, cross, and vertical winds 0.1 0.2 0.0 0.1 0.2
 HFR [33] with HL09: only cross and vertical winds 0.1 0.1 0.0 0.1 0.2
 HFR [35] with HL09: along-wind, cross, and vertical winds 0.2 0.2 0.0 0.1 0.3
 HFR [35] with HL09: only cross and vertical winds 0.2 0.2 0.0 0.1 0.3
  1. Data period is 1-month (March 2015) from HU site. Italic indicates the methods applied in this study