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UV Raman lidar Chilbolton Observatory Review April 2003-2004. Judith Agnew CCLRC Rutherford Appleton Laboratory Radio Communications Research Unit. Summary of events.
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UV Raman lidarChilbolton ObservatoryReview April 2003-2004 Judith Agnew CCLRC Rutherford Appleton Laboratory Radio Communications Research Unit
Summary of events • CWAVE campaign June-July 2003: comparison of UV Raman lidar data with Met Office Radiometrics radiometer and co-located Aberystwyth polarimetric lidar. • Examples of high cirrus cloud. • Laser repair. • Implementation of new data acquisition system.
Lidar, radiometer, radiosonde humidity mixing ratio Average signal in each radiometer range bin during lidar measurement period Lidar Radiometer Radiosonde
Water vapour measurements 13/06/03 Raman lidar Radiometer Difference
Water vapour measurements 25/06/03 Raman lidar Radiometer Difference
High cirrus clouds 07/05/03 09/06/03
Lidar upgrades • New data acquisition system about to be delivered. Installation work to begin immediately, while keeping existing system operational. • Will upgrade the capabilities from 8 bit analog to 12 bit analog and photon counting • Photon counting will improve the measurement of small signals, especially by night. • Higher resolution analog measurements beneficial when photon counting is not suitable, for example by day in the Raman scattering channels. • Laser underwent extensive maintenance and now has much improved beam power.