Articles | Volume 9, issue 3
Research article
30 Mar 2016
Research article |  | 30 Mar 2016

Re-evaluating the Frankfurt isothermal static diffusion chamber for ice nucleation

Jann Schrod, Anja Danielczok, Daniel Weber, Martin Ebert, Erik S. Thomson, and Heinz G. Bingemer

Abstract. Recently significant advances have been made in the collection, detection and characterization of ice nucleating particles (INPs). Ice nuclei are particles that facilitate the heterogeneous formation of ice within the atmospheric aerosol by lowering the free energy barrier to spontaneous nucleation and growth of ice from atmospheric water and/or vapor. The Frankfurt isostatic diffusion chamber (FRankfurt Ice nucleation Deposition freezinG Experiment: FRIDGE) is an INP collection and offline detection system that has become widely deployed and shows additional potential for ambient measurements. Since its initial development FRIDGE has gone through several iterations and improvements. Here we describe improvements that have been made in the collection and analysis techniques. We detail the uncertainties inherent in the measurement method and suggest a systematic method of error analysis for FRIDGE measurements. Thus what is presented herein should serve as a foundation for the dissemination of all current and future measurements using FRIDGE instrumentation.

Short summary
In this manuscript we describe technical and analytical advances that have been implemented for use with the Frankfurt ice nuclei measurement system known as FRIDGE. In particular we focus on a new collection apparatus and improved data analysis protocol. We also provide an outline of how FRIDGE data should be interpreted and reported. Results from an example case study are presented and help to contextualize FRIDGE data with respect to other measurement techniques and modeling efforts.