Ammmonia measurements

We use a Mini-DOAS instrument to measure ammonia. It is a miniature version of the Differential Optical Absorption Spectroscopy, allowing to measure atmospheric NH3, as well as NO, and SO2. It is an open-path sensor, thereby overcoming the problem that NH3 sticks to surfaces. We investigate the use of this instrument in the Cabauw measurement tower and in different campaigns at farmhouses.