Harvard Forest General Trace Gas Data
Data is sorted by year in files hfYYgen, where YY is the last two digits of the year.
Each data file contains four header lines followed by the data arranged in 35 columns.
Header line 3 contains datum names for each column. Header line 4 lists units for each
column. Columns are sepearted by spaces, including header lines with datum names and
units. Missing or invalid data is reported as NA. The data file for the year 1997
combines data from Wosfy and Fitzgarrald. The file data_key97 contains a table
identifying the source (i.e., Wofsy or Fitzjarrald) of each measurement. The data
contained in the hfYYgen files is described in the table below. Time (EST) is the
day of the year with the hour given as the decimal equivalent (1 = 24 hours; e.g.
164.5 is 12 noon on day of year 164).
Column Name Description Units
1 time midpoint time of hourly average (EST) days
2 wspd wind speed from sonic m/s
3 wdir wind direction from sonic degrees
4 eddyT air temperature from sonic C
uncorrected for H2O
5 eddyQ water vapor density g/m3
6 O3mlb ozone mixing ratio ppb
7 NOy NOy mixing ratio ppt
8 sNOy standard deviation of NOy mixing ratio ppt
9 CO carbon monoxide mixing ratio ppb
10 sCO standard deviation of CO mixing ratio ppb
11 FCO2 carbon dioxide flux umole/m2/s
12 Fmom momentum flux cm2/s2
13 Fheat sensible heat flux W/m2
sonic temperature uncorrected for H2O
14 Fh2o water vapor flux mg/m2/s
15 FO3 ozone flux umole/m2/hr
16 Fnoy NOy flux umole/m2/hr
17 RNET net radiation W/m2
18 PAR_12.7 photosynthetically active radiation uE/m2/s
at 12.7 m
19 PAR_29 photosynthetically active radiation uE/m2/s
at 29.0 m
20 RH_27.9 relative humidity at 27.9 m %
21 RH_22.6 relative humidity at 22.6 m %
22 RH_15.4 relative humidity at 15.4 m %
23 RH_7.6 relative humidity at 7.6 m %
24 RH_2.5 relative humidity at 2.5 m %
25 Ta_27.9 air temperature at 27.9 m C
26 Ta_22.6 air temperature at 22.6 m C
27 Ta_15.4 air temperature at 15.4 m C
28 Ta_7.6 air temperature at 7.6 m C
29 Ta_2.5 air temperature at 2.5 m C
30 Ts_srf soil temperature near surface C
31 Ts_50 soil temperature 50 cm depth C
32 Ts_20 soil temperature 20 cm depth C
33 CO2 mean CO2 mixing ratio at 29.0 m ppm
34 CO2stg CO2 canopy storage umole/m2/s
35 Patm atmospheric pressure Pa
36 Ts_srf.adj adjusted soil temperature near surface C
(see file revision_detail)
ppm = parts per million, ppb = parts per billion, ppt = parts per trillion
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If we feel that we should be acknowledged or offered participation as authors, we will let
you know and we assume that an agreement on such matters will be reached prior to
publishing the data. If your work directly competes with our analysis we may ask that we
have the opportunity to submit a manuscript before you sumbmit one that uses our data.