Aircraft Hand Held Microtops Measurements

On various occasions Dr. Antony Clarke and I (John Porter) have carried out hand held sun photometer measurements from light aircraft. As it turns out we were not the first to do this. Dr. Glen Shaw and Dr. Hal Maring had also done this type of measurements independently. Recently our paper which discusses this  topic has been accepted (in J. Atmospheric and Oceanic Technology, 2007). Although the method can provide quantitative mesurements, it involves a significant amount of effort and approximately 90% of the measurements are rejected. 

The figure below shows measurements made during a United Arab Emirates experiment using a hand held sun photometer. The open circles are the rejected sun photometer measurements. The solid circles are those that are considered to be good. The solid line is the aircraft altitude (see label on right side of graph).