Sodar measurements have been used to estimate the mixing height for ab
out 20 yr, nevertheless the issue is still the subject of controversia
l discussion. The paper attempts to critically examine the methods and
results of mixing height determination from sodar data that have been
reported in the literature. The theoretical base, the methods suggest
ed, the automatization of algorithms, and the intercomparison of sodar
-based mixing height values with data from independent measurements an
d models are briefly discussed. An assessment is given of sodar capabi
lities in comparison with other profiling techniques. It is concluded
that sodar data may be used to derive reliable mixing height informati
on in many situations which are of special relevance for environmental
monitoring, namely in stagnant weather situations with low mixing hei
ght values between about 50 and 500-1000 m, depending on the type of t
he sodar. However, the algorithms available up to now for their automa
tic evaluation appear not yet reliable enough to be recommended for op
erational purposes, and a control of the output by a trained analyst i
s advisable. Simultaneous operation of sodars and other remote sensing
systems (lidar, wind profiler) is shown to be a promising way to over
come the range limitations of sodars and to allow continuous mixing he
ight estimation throughout the complete diurnal cycle. (C) 1997 Elsevi
er Science Ltd.