847 
obtain adequate sea-truth data with the wide set of conventional oceanographic 
methods and instruments available on-board a ship. Moreover, according to our 
practice, shipborne lidars appear to be a useful tools in framework of complex 
research survey, being capable of providing real-time information about 
studied phenomena during all motions of the ship in the area. This allows, for 
instance, fast corrections of preliminary stated positions of the stations for 
detailed analysis of features found by lidar along-track monitoring. 
We should note that the helicopter may be considered as potentially very 
promising carrier for lidar-fluorosensor system (for example, see Bristow et 
al., 1985). The major advantage of that platform is the capability for varying 
its speed in a wide range (including stopping for detailed studying the found 
structures of particular interest and even sampling the water for further lab 
analysis). Due to its potential operating at low altitudes (about 100 m) the 
compact and low-consuming helicopter-based lidar-fluorosensor could be deve 
loped. Such a system could be effectively used for environmental survey in 
coastal zones. Another attractive opportunities would be provided by develop 
ment of lidar mounted at compact ship-based helicopter. In particular, this 
approach may help to solve the problem of synoptic covering during ship-going 
activity. 
4 - LIDAR PROFILING AND MAPPING IN THE SEA 
In the framework of present paper we will give a brief review of some results 
obtained with shipborne lidar-fluorosensor developed at Moscow university. 
Additional information on various applications of lidar systems in 
oceanography one may find in cited papers. 
4.1. Lidar Profiling in the North-Western Atlantic and the Mediterranean Sea 
An example of along-track profile of chlorophyll-a is shown in Fig.3 
(shipboard lidar monitoring). The measurements were conducted in the 
North-Western Atlantic on the 20-21 of April, 1990 (Gorbunov and Chekalyuk, 
1993). The most interesting feature of the presented profile is the large area 
of powerful spring bloom of phytoplankton. Further sample analysis indicated 
that this bloom was caused by Phaeocystis sp. algae. There was considerable 
patchiness within the bloom area with mesoscale quasi-periodical structures. 
According to our estimations based on lidar sensing and laser measurements of 
relative yield of variable Chl-a fluorescence (Chekalyuk and Gorbunov, 1992b), 
The North-Western Atlantic, 
April 20-21, 1990 
-48 -47 -46 -45 -44 -43 -42 
WESTERN LONGITUDE (degrees) 
Figure 3. Along-track Profile of Chlorophyll-a Concentration