It is suggested that the CNR 1 is mounted at a height of at least 1.5 metres above the surface, to
avoid shading effects of the instruments on the soil and to promote spatial averaging of the
measurement. If the instrument is H metres above the surface, 99% of the input of the lower
sensors comes from a circular area with a radius of 10 H. Shadows or surface disturbances with
radius < 0.1 H will affect the measurement by less than 1%.
The Net Radiometer should be installed horizontally, using the level on the body of the CNR 1.