TITLE: Mesonet ABLE Automatic Weather Station (AWS) Data [DOE]
CONTACTS:
Richard L. Coulter - ER 203
Argonne National Laboratory
9700 South Cass Avenue
Argonne, IL 60439
Voice: 630 252-5833
Fax: 630 252-5498
Email: rl_coulter@anl.gov
1.0 DATA SET OVERVIEW
This data set contains 1-minute resolution surface meteorological
data from the Atmospheric Boundary Layer Experiments (ABLE) operated
by the Argonne National Laboratory in the Walnut River Watershed in
Butler County Kansas (east of Wichita). The ABLE Automated Weather
Station (AWS) Network consists of five stations. Data cover the
period from 20 May to 7 July 2003 The data are in columnar ASCII
format.
2.0 INSTRUMENT DESCRIPTION
2.1 Instrumentation
The AWS stations directly measure:
Wind speed at 10 m, Precision: 0.01 m/s; Uncertainty: +/-1% for
2.5 to 30 m/s, increases to +/-0.5 m/s when 0.5 m/s is reported.
Propellor anemometer and wind vane, R. M. Young Model 05103 Wind Monitor
Wind direction at 10 m, Precision: 0.1 deg; Uncertainty: +/-5 deg
Air temperature at 2 m, Precision: 0.01 C; Uncertainty: +/-0.7 C
(This will eventually improve when an aspirated reference is obtained.)
Thermistor and Vaisala RH, Campbell Scientific Model HMP35C Temperature and
Relative Humidity Probe
Relative humidity at 2 m, Precision: 0.1% RH; Uncertainty: +/-2.06% RH
(0% to 90% RH), +/-3.04% RH (90% to 100% RH)
Thermistor and Vaisala RH, Campbell Scientific Model HMP35C Temperature and
Relative Humidity Probe
Barometric pressure at 1 m, Precision: 0.01 kPa; Uncertainty: +/-0.035 kPa
Digital barometer, Vaisala Model PTB201A
Precipitation, Precision: 0.254 mm; Uncertainty: +/-0.254 mm (unknown
during strong winds and for snow)
Electrically heated, tipping bucket precipitation gauge, MetOne Model 385
Rain/Snow Gage
Data logger: Campbell Scientific Model CR10X-1M Measurement & Control Module
with 1 MByte memory; Precision: A function of input type and range,
Uncertainty: 0.2% of Full Scale Range for Analog Inputs
2.2 Station Locations
UTM km (Zone 14)
Site 99 deg Meridan DEG dddmmmsss ddmm.mm Alt (m)
----------------------------------------------------------------------------------
Augusta, KS Central Site 4166.2 UTMN km 37.626 37 37' 32" 37 37.53' 400
686.9 UTME km 96.882 96 52' 55" 96 52.92'
Beaumont, KS 4167.1 UTMN km 37.627 37 37' 38" 37 37.64' 478
717.2 UTME km 96.538 96 32' 19" 96 32.32'
Oxford, KS 4126.7 UTMN km 37.273 37 16' 25" 37 16.41' 360
668.8 UTME km 97.095 97 05' 45" 97 05.75'
Smileyberg, KS 4154.6 UTMN km 37.521 37 31' 15" 37 31.26' 408
689.6 UTME km 96.855 96 51' 18" 96 51.30'
Whitewater, KS 4189.5 UTMN km 37.841 37 50' 26" 37 51.43' 416
659.6 UTME km 97.186 97 11' 10" 97 11.16'
For file names the station IDs are as follows:
Augusta cs
Beaumont be
Oxford ox
Smileyberg sm
Whitewater wh
Topo maps and aerial photos are available at:
gonzalo.er.anl.gov/ABLE/sitelatlon.html
3.0 DATA COLLECTION AND PROCESSING
The AWS sensors are mounted on a 10 meter, triangular tower, except for the
rain gauge.
The wind monitor propeller anemometer produces a magnetically controlled AC
output whose frequency is proportional to the wind speed. The Wind Monitor
direction vane drives a potentiometer, which is part of a resistance bridge.
The Wind Monitor is mounted on a cross-arm at a height of 10 m.
The T-RH probe temperature sensor, a thermistor, is connected into a
resistance bridge. The Vaisala RH circuitry produces a voltage that is
proportional to the capacitance of a water vapor absorbing, thin polymer
film. The T-RH probe is mounted in an R. M. Young Mode l43408 Gill Aspirated
Radiation Shield. The Radiation Shield is mounted at a height of 2 m on the
southern face of the tower.
The barometric pressure sensor uses a silicon capacitive pressure sensor
and is housed in a weatherproof enclosure along with a data logger, a
storage module, and serial communications equipment, all mounted on the
tower at a height of 1 m.
The rain-snow gauge has a 12-inch orifice and is located near the tower. A
thermostatically controled heater melts frozen precipitation. The water is
funneled to a tipping bucket, which triggers a magnetic reed switch. An
Alter Shield is used to increase the reliability of rain collection in high
winds and of snow collection.
The data logger measures each input once per second except for barometric
pressure, which is measured once per minute. The vapor pressure is computed
from the air temperature and relative humidity. The data logger produces
1- and 30-min averages of wind speed, vector-averaged wind speed,
vector-averaged wind direction, air temperature, relative humidity, and
vapor pressure. The standard deviation of the wind direction is computed by
an algorithm. The 1-min output includes the barometric pressure reading and
total precipitation during the minute. The 30-min output includes the battery
voltage and 30-min-total precipitation. The 30-min output also includes the
standard deviations of wind speed, temperature, relative humidity, vapor
pressure, and barometric pressure.
UCAR/JOSS conducted no processing or quality control on these data.
4.0 DATA FORMAT AND FILE NAMING
4.1 Data Format
These data are in columnar ASCII format.
AWS data header
TairC average air temperature in deg C taken at 2 m
RH_% average relative humidity in % taken at 2 m
VP_hPa water vapor pressure in hPa computed from average RH
W_spd average wind speed in m/s taken at 10 m (except at temporary sites)
W_vect magnitude of vector-averaged winds in m/s taken at 10 m
Wdir direction angle from North of vector-averaged winds taken at 10 m
WdirSD standard deviation of 10 m wind direction computed by algorithm
BarohPa barometric pressure in hPa taken at 1.5 m (not present at BE, WH, OX)
Prcp_mm precipitation in mm
All times are UTC.
4.2 File Naming conventions
wh020608.awstxt
where:
wh is the station ID (here Whitewater).
02 is the year (2002)
06 is the month (June)
08 is the day of month
5.0 DATA REMARKS
None.
6.0 REFERNCES
ABLE Home Page: gonzalo.er.anl.gov/ABLE/index.html