Im. Povey et al., A BROAD-BAND LIDAR FOR THE MEASUREMENT OF TROPOSPHERIC CONSTITUENT PROFILES FROM THE GROUND, J GEO RES-A, 103(D3), 1998, pp. 3369-3380
In this paper we describe a novel lidar that combines differential UV-
visible absorption spectroscopy and the lidar technique. The critical
and novel element of the system is the use of an imaging spectrometer
in conjunction with a two-dimensional CCD detector array to simultaneo
usly spectrally and temporally resolve backscattered radiation. To exp
loit this approach, the lidar system utilizes a broadband laser output
of 10-20 nn full width at half maximum tunable across the UV-visible
spectral region, thus allowing the simultaneous measurement of multipl
e molecular species by the differential optical absorption spectroscop
y technique. To demonstrate the flexibility of the technique for tropo
spheric composition monitoring we present initial results for both ela
stic and inelastic (Raman) backscatter and for absorption studies in t
he spectral regions where NO3 and H2O absorb. In addition, the techniq
ue has applicability for a wide range of molecules including O-3, NO2,
and other spectrally structured absorbers and for atmospheric tempera
ture sounding, which may be derived from either rotational Raman retur
n or temperature dependent absorptions such as those of O-2.