ChEAS below canopy flux station data - Willow Creek
Location:  45 deg 48.47' N, 90 deg 04.72' W
Elevation:  approx. 520 m above sea level
Prepared by Bruce D. Cook, Penn. State Univ. (bcook@essc.psu.edu, 612-624-9796)

**PLEASE NOTE**  Permission to download this data does not grant permission to 
use the information contained in that file for publication. Please contact the 
owner of the file or the appropriate faculty member before use of any such 
information in a publication. 

FILE STRUCTURE:   monthly data files named bcanopyYYYY (YY=year, MM=month)
FILE COMPRESSION: gzip (information/software available at http://www.gzip.org)
FILE FORMATS:     comma delimited ASCII
BAD VALUES:       elements are flagged by -999

SAMPLING FREQUENCIES (current):

DATA OUTPUT (current): 10 minute averages  

DATA ELEMENTS (elements in columns, from left to right):     
year        = YYYY
jdate       = Julian calander date (LST time)
hrmin       = HHMM (0 to 2359 LST; signifies the end of the measurement interval)
fc_irga     = CO2 flux (mgC/m^2,s)
le_irga     = H2O flux (W/m^2)
hs          = sonic sensible heat flux (W/m^2)
h           = tc sensible heat flux (W/m^2)
tau         = momentum flux density (kg,m/s^2)
ustar       = friction velocity (m/s)
uz_uz       = covariance (m/s)^2
uz_ux       = covariance (m/s)^2
uz_uy       = covariance (m/s)^2
uz_co2      = covariance (mg/m^2,s)
uz_h2o      = covariance (g/m^2,s)
uz_ts       = covariance (m,deg C/s)
uz_fw       = covariance (m,deg C/s)
ux_ux       = covariance (m/s)^2
ux_uy       = covariance (m/s)^2
ux_co2      = covariance (mg/m^2,s)
ux_h2o      = covariance (g/m^2,s)
ux_ts       = covariance (m,deg C/s)
ux_fw       = covariance (m,deg C/s)
uy_uy       = covariance (m/s)^2
uy_co2      = covariance (mg/m^2,s)
uy_h2o      = covariance (g/m^2,s)
uy_ts       = covariance (m,deg C/s)
uy_fw       = covariance (m,deg C/s)
co2_co2     = co2 covariance (mg/m^3)^2
h2o_h2o     = h2o covariance (g/m^3)^2
ts_ts       = t covariance (deg C^2)
fw_fw       = fine wire thermocouple covariance (m/s)^2
rn_avg      = net radiation, average (W/m^2)
ux_avg      = x wind speed, average (m/s)
uy_avg      = y wind speed, average (m/s)
uz_avg      = z wind speed, average (m/s)
co2_avg     = co2 mixing ratio, average (mg/m^3)
h2o_avg     = h2o mixing ratio, average (g/m^3)
ts_avg      = sonic virtual temperature, average (deg C)
fw_avg      = fine wire thermocouple temperature, average (deg C)
rho_avg     = density of moist air, average (kg/m^3)
h2o_hmp_avg = h2o mixing ratio from T/RH probe, average (g/m^3)
t_hmp_avg   = air temperature from T/RH probe, average (deg C)
rh_hmp_avg  = relative humidity from T/RH probe, average (%)
atm_p_avg   = atmospheric pressure from irga, average (kPa)
tc_ref_avg  = thermocouple reference, average (deg C)
wdir_tnorth = wind direction, average (degrees from true north)
wdir_csat3  = wind direction, average (degrees relative to CSAT3)
wspeed      = wind speed, average (m/s)
rslt_wspd1  = ? (m/s)
rslt_wspd2  = ? (m/s)
stdev_wdir  = wind direction, std deviation (degrees from true north)
bvolt_avg   = battery voltage (VDC)
rho_stdev   = density of moist air, std deviation (kg/m^3)
h2o_stdev   = h2o mixing ratio from T/RH probe, std deviation (g/m^3)
t_stdev     = air temperature from T/RH probe, std deviation (deg C)
rh_stdev    = relative humidity from T/RH probe, std deviation (%)
n_total     = number of scans with at least 1 CSAT or IRGA warning? (unitless)
csat_diag   = CSAT3 diagnostic word (unitless)
irga_diag   = IR-7500 diagnostic word (unitless)
del_t_f_tot = delta temperature warning flag (unitless)
track_f_tot = tracking (signal lock) warning flag (unitless)
amp_h_f_tot = Amplitude high warning flag (unitless)
amp_l_f_tot = Amplitude low warning flag (unitless)
chop_f_tot  = Chopper warning flag (unitless)
det_f_tot   = Detector warning flag (unitless)
pll_f_tot   = PLL warning flag (unitless)
sync_f_tot  = Synchronization warning (unitless)
agc_avg     = Automatic gain control (unitless)

EQUIPMENT AND SENSORS:
CSI CR5000 datalogger
CSI CSAT3 sonic anemometer
LICOR LI-7500 open path infrared gas analyzer (co2 and h2o)
Vaisala HMP45C temperature and relative humidity probe
CSI FW05 fine wire thermocouple
REBS Q7.1 net radiometer
RAD Short haul modems
Toshiba Libretto portable computer and Iomega 1 Gb Jaz drive

HISTORY:        
May 2002.  Setup 2m tripod about 50m north of the above canopy flux tower.