Shipboard oceanographic fluorescence lidar development and evaluation

• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Antarctic; Drake Passage; South Shetland Islands; The Antarctic; Antarc*
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.579.591; http://las.physik.uni-oldenburg.de/publications/paper/sbl.pdf

The prototype of a shipboard lidar for oceanographic applications uses the 355 nm wavelength of a Nd:YAG-Laser to excite fluorescence of gelbstoff and chlorophyll in seawater. The lidar was installed on board the research vessel Polarstern at the end of 1996 during cruise ANT XIV/2. Measurements were carried out around the South Shetland Islands and in the Drake Passage between South America and the Antarctic Pen-insula. Remotely measured depth profiles of the beam attenuation coefficient in the upper water column were derived from time resolved measurements of water Raman scattering. In the same way, depth profiles of gelbstoff and chlorophyll were derived from laser-induced fluorescence signals. These depth profiles were continuously taken while the ship was underway with a penetration depth of up to 40 m, depending on the de-tection wavelength and turbidity of the water. The data are compared with in situ fluorescence measurements. Limitations and advantages of remotely measured lidar profiles and in situ measurements with submerged probes are discussed. 1.