J. Laubach et Kg. Mcnaughton, A spectrum-independent procedure for correcting eddy fluxes measured with separated sensors, BOUND-LAY M, 89(3), 1998, pp. 445-467
We investigate dux underestimates in eddy correlation measurements that are
caused by horizontal separation of the sensors. A common eddy correlation
setup consists of a sonic anemometer and a humidity sensor which, because o
f its bulk, must be placed some distance away from the sonic path, leading
to a flux loss (of latent heat). Utilizing an additional fast temperature s
ensor placed near the humidity sensor, we develop st procedure for correcti
ng for this loss. The procedure simultaneously corrects the sensible heat f
lux for the difference between true temperature and sonic temperature. Our
correction procedure, which does not depend on the shape of the cospectrum,
is then compared to the widely-used procedure following Moore (1986), whic
h assumes a cospectral model ('Kansas Model'). Both correction methods are
applied to data collected within the internal boundary layer over a rice pa
ddy, downwind of arid land. Under conditions of good fetch, they were found
to agree well. Under poor fetch conditions, the model-based correction ten
ded to be too small, while the spectrum-independent combined correction was
robust. The latter is thus recommended for situations where the cospectral
shape can be expected to deviate from the 'Kansas' shape.