Air Temperature

TAIR (1.5 m)

The 5-minute average air temperature at a height of 1.5 meters above the ground. (Note: The air temperature sensors were removed from the micronets during December 2008 through March 2009.) Archived air temperature data from the micronets can be downloaded on the Data Request Page.

This sensor is quite rugged and accurate. However, power and cost limitations dictated using an unaspirated radiation shield. Unfortunately, such shields can create temperature errors of several degrees Celsius when the wind is calm (less than 1 m/sec) and radiation is strong (more than 800 Watts per square meter). Radiation at high sun angles near 70 degrees seem to induce the worst errors.

Sensor Used:

Vaisala HMP45C

Standard Units:

degrees Celsius

Accuracy:

± 0.5 ºC when windspeed is 6 m/s
± 1.0 ºC when windspeed is 3 - 6 m/s
± 1.5 ºC when windspeed is 2 - 3 m/s
± 3.0 ºC when windspeed is 1 - 2 m/s