The objective of this project is to develop an automated sampling system that can record the dry deposition of fine particles (@ 2.5Am). The recent Symposium on Precipitation Scavenging, Dry Deposition and Resuspension, published in the Proceedings of the Fourth International Conference, Santa Monica,'CA, NovemberDecember 1982, has clearly elucidated three points: (1) The paucity of reliable and widely applicable data and the large range of values for same, especially deposition velocities; (2) the wide array of currently-in-use instrumentation and the lack of agreement as to the best techniques; and (3) the clear need for better particle monitoring instrumentation (in terms of the specific measuring techniques) e.g., resolution, response time, etc. From a monitoring strategy viewpoint, the requirement necessitates the accurate collection of the species of interest (to allow for subsequent chemical analyses) i.e., those that contribute substantially to the overall acidification process as well as a reliable, cost-effective approach. The proposed automated dry deposition monitor represents the modification of a tested and proven automatic particle-sampling system to provide for the determination of nitric acid flux values and ultimately other important atmospheric constituents such as acid sulfates and sulfuric acid. The system allows for the filter collection of up to nine samples/station, sampling duration programmable from 1-24 hrs in 1-hour increments with variable, selected time intervals between samples. The final objective is to provide a sound, reliable technology at a cost not to exceed $5,000/unit.AnticipatedResults Potential Commercial Applications as described by the awardee:The proposed automated dry deposition monitor will provide a reliable, proven, cost-effective instrument to record deposition flux values for atmospheric constituents contributing to the acidification process of an ecosystem. Additionally, researchers and practitioners in all fields of atmospheric monitoring and modeling (to include public and private sectors) will have access to an automated sampler that works.
