Below is a chart of atmospheric Aerosols based on altitude and time.
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| Atmospheric Research | ||||||||||||||||||||||||||||
| LIDAR can be used to detect very small particles in the atmosphere. Water vapor, pollution, and other particles can be tracked to show weather patterns and the like. The beam is scattered by the small particles in the air, and then some of the light is reflected back to the system. | ||||||||||||||||||||||||||||
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| http://www.rap.ucar.edu/staff/tardif/CUprojects/ATOC5235/images/lidar_principle.gif | ||||||||||||||||||||||||||||
| A LIDAR system cannot detect particles smaller than the wavelength of the beam. Therefore a very small wavelength has to be used for atmospheric research. | ||||||||||||||||||||||||||||
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| http://web.mit.edu/jync/www/lidar_radar.gif | ||||||||||||||||||||||||||||
| Above is an example of an atmospheric scan. Atmospheric scans basically take 3D space to put it on a 2D chart, so ultimately only one small vertical "slice" of space can be scanned. The Y axis is the altitude of this "slice" and the X axis shows the time period. By emitted rapid pulses of the laser beam, the LIDAR can detect several positions of a particle over a short period of time. This allows the LIDAR to calculate the speed and direction of the particle. Below is a chart of atmospheric Aerosols based on altitude and time. |
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| http://oea.larc.nasa.gov/PAIS/DIAL1.gif | ||||||||||||||||||||||||||||
| In this chart, the X axis covers the time period which the data was taken over. The red and black areas are the altitudes/times that have the highest concentrations. White areas there is no data for. This chart shows how the aerosols increased in concentration over time at some altitudes, but the sky remained clear higher up. | ||||||||||||||||||||||||||||
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