TITLE: Mesonet ABLE Automatic Weather Station (AWS) Data [DOE]


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


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 13 May to 25 June 2002 The data are in columnar ASCII 


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:


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.


4.1  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

        wh is the station ID (here Whitewater).
        02 is the year (2002)
        06 is the month (June)
        08 is the day of month




ABLE Home Page: gonzalo.er.anl.gov/ABLE/index.html