TA-49 Station Description

Alternate Name(s): Bandelier

Measurements:
The TA-49 station includes a 46-m tower instrumented for wind and temperature at three levels and near-surface instrumentation for measuring temperature, moisture, precipitation, and shortwave solar irradiance. See Table 13.4 in the Meteorological Monitoring Plan for measurement details and Table 13.3 in the same document for definitions of variables.

Data Type Record Begins Record Ends
15-min data June 24, 1987 (still active)
24-h data June 24, 1987 (still active)

Site Description:
The TA-49 station is located on the Pajarito Plateau on high ground between two small tributaries of Ancho Canyon. The view of the station, as shown in the above photograph, is looking east toward the Sangre De Cristo Mountains.  The station's tower is seen in the middle of the photograph.  The fetch within a few hundred meters of the tower is over short grasses and widely scattered low shrubs. In the vicinity of the tower, the plateau tilts at about 2.3 degrees to the east-southeast.  The terrain slopes gently to the south and more abruptly to the north into the two tributaries of Ancho Canyon.

Location and Elevation:

Coordinate System x y
NAD 27 State Plane Coordinates (ft) 485549 1751253
UTM, Zone 13 (m) 382616.49 3964021.35
Longitude & Latitude -106° 17' 57.5" 35° 48' 47.9"

Station elevation is 7045 ft (2147.9 m) above sea level.

The tower is LANL structure no. TA-49-0123, and the datalogger shed is LANL structure no. TA-49-0138.

Data Quality:

General Remarks:
For the most part, all suspect data have been replaced with an asterisk (*). Occasionally you will see days on which all the 15-min data appear good, but some of the 24-h summary values are missing. Lightning strikes, momentary power outages, or the need to reload the datalogger program may be the cause. In these cases, you can estimate a 24-h value from the 15-min data.

See Section C.1.b and c of the Meteorological Monitoring Plan for details on sampling and general remarks concerning accuracy.

Qualifying remarks are organized by data type (for example, wind, atmospheric state, etc.), and we use our standard variable names, as defined in Table 13.3 of the Meteorological Monitoring Plan.

Wind Variables:
Wind direction measurements (dir) from November 8, 1989, to April 19, 1990, were affected by an inappropriate resistor in the circuit. Because of the averaging done in the datalogger, there is no accurate way of reconstructing these data. If you need wind direction data during the period of time, contact a meteorologist.

The measurement of the vertical velocity (w) has been multiplied by 1.25 to correct for the non-cosine response of the propeller. All quantities derived from the w signal include this correction. The w signal is occasionally affected by wet snow and ice. Although we have attempted to edit the data when this happens, you will occasionally see periods of several hours when w and its standard deviation (sdw) go to zero during the winter; a frozen propeller is the cause.

Most of the instantaneous wind gust directions (dirgst) are erroneous.

Atmospheric State Variables:
Occasionally one encounters relative humidity (rh) values exceeding 100%; we recommend changing these values to 100%.

Precipitation-related Variables:
No known problems.

Radiative Energy Variables:
During and for some time after periods of snow or frost formation, the dome of the upward looking pyranometer may become snow or ice covered. In such instances the shortwave irradiance (swdn) is diminished. Our editing has not been consistent: In portions of the record we attempted to remove these snow and frost effects and in other portions we decided not to edit. In general, it is difficult to decide when the melting is complete and the signal is back to normal.

As a result of a change in the calibration standard used by the manufacturer, measurements of swdn are 5% too large from the beginning of the record to February 22, 1995 at  0915 MST.