Data from: Automation and Heat Transfer Characterization of Immersion Mode Spectroscopy for Analysis of Ice Nucleating Particles. In Center for Aerosol Impacts on Chemistry of the Environment (CAICE)

The heat transfer properties of the SIO-Automated Ice Spectrometer (AIS), an ice nucleation measurement technique, are characterized using a finite-element analysis based heat transfer simulation that was developed using the 3D Design Software SOLIDWORKS. The heat transfer simulation is proposed as a tool that could be used to explain the sources of bias in temperature measurements in ice nucleation particles (INP) measurement techniques, and ultimately explain the observed discrepancies in measured ice nucleation particles (INP) freezing temperatures between different instruments. The simulation results posted here show that a difference of +8.4 °C between the well base temperature and the headspace gas results in an up to 0.6 °C stratification of the aliquot, whereas a difference of +4.2 °C or less results in a thermally homogenous water volume within the error of the thermal probe, ±0.2 °C. The results also show that there is a strong temperature gradient in the immediate vicinity of the aliquot, such that without careful placement of temperature probes, or characterization of heat transfer properties of the water and cooling environment, ice nucleation particles (INP) measurements can be biased toward colder temperatures. Using the modified immersion mode technique, the Automated Ice Spectrometer (AIS) measurements of the standard test dust illite NX are reported and compared against 6 other immersion mode droplet assay techniques featured in (Hiranuma et al., 2015) that used wet suspensions.