Description of flux data for Sylvania Wilderness / Helen Lake Tower Last update: 22 May 2003, Ankur Desai Filename: Sylvaniayy_flux.txt Notes: Missing or invalid data is reported as -999. Time is recorded at the beginning of average period. The average interval is 30 minutes. Local standard time (CST) is -6 UTC FORTRAN Format code is: (i4.4,i3,i3,f5.1,i4,f6.3,9f12.3,i4,f12.3) Value of flag (Column 16): -1) Preliminary data – no full year calibrations or screening 0) Non-preliminary data, no screening tests 1) Non-preliminary data, good or no data Storage terms for LE,H and G are computed 2) Non-preliminary data, small u*, NEE is gap-filled 3) Non-preliminary data, NEE from lake (30-90 degrees). NEE is gap-filled 4) Gap-filled missing or bad NEE- using PAR/T fitted functions 5) Gap-filled missing or bad NEE- using NEE multi-week moving window ensemble -2,-3,-4,-5 preliminary screened data, same meanings as positive values if flag has a one in front = (11,12,13,14,15) = C storage term is filled Column Name Description Unit Range/Notes 1 Year Year Year 2000-3000 2 Month Month Month 1-12 3 DOM Day of Month Day 1-31 4 LST Local Standard Time Hour 0.0-23.5 5 DOY Day of Year Day 1-366 6 F_day Fraction of Day 0-1 7 Storage Rate of change of umol/m2s CO2 storage - 36 m 8 Flux CO2 flux - 36 m umol/m2s 9 NEE Net ecosystem exchange umol/m2s (Flux+Storage), filled 10 NetRad Net radiation – 36 m watts/m2 11 PAR Photosynthetic active umol/m2s radiation – 36 m 12 LE Latent heat flux - 36 m watts/m2 13 H Sensible heat flux – 36 m watts/m2 14 G Soil heat flux – 75mm below watts/m2 15 U* Friction velocity – 36 m m/s 16 Flag Data quality flag 17 oNEE original non-screened NEE umol/m2s