Backscattersonde: a new instrument for atmospheric aerosol research.

A relatively simple balloonborne device for measuring the local aerosol backscatter at multiple wavelengths has been developed and field tested. The instrument produces detailed profiles which are inherently similar to those generated from lidar soundings. It is also sensitive, being able to measure the 20-km stratospheric aerosol background layer with a signal-to-noise ratio of approximately 100:1. An important feature of this device is its ability to be calibrated in an absolute sense. Theoretical considerations show that the measurements can be accurately converted to aerosol mass loading in the stratosphere for conditions ranging from background to heavy volcanic influence. The instrument is not expected to replace other observational techniques; rather it provides highly complementary information as well as furnishes a cost-effective alternative to measurement systems available to only a few scientists.