Data Files Accompanying: “Best practices for precipitation sample storage for offline studies of ice nucleation”
Authors:  Charlotte M. Beall, Dolan Lucero, Thomas C. Hill, Paul J. DeMott, M. Dale Stokes, Kimberly A. Prather
Journal: in review with Atmospheric Measurement Techniques

Contact: 
Kimberly A. Prather, kprather@ucsd.edu, Scripps Institituion of Oceanography / Department of Chemistry and Biochemistry, University of California San Diego

Cite as:
Beall, Charlotte M.; Lucero, Dolan; Hill, Thomas C.; DeMott, Paul J.; Stokes, M. Dale; Prather, Kimberly A. (2020). Data from: Best practices for precipitation sample storage for offline studies of ice nucleation. In Center for Aerosol Impacts on Chemistry of the Environment (CAICE). UC San Diego Library Digital Collections. https://doi.org/10.6075/J0M32T8B

The data directory contains the following data in csv files:

	1. INP_Concentrations: Contains cumulative ice nucleating particle (INP) spectra for fresh and stored precipitation samples between -35 and 5 degrees C, corrected for freezing events in instrumental control sample (ultrapure water dispensed from Sartorius arium(R) Pro) and the storage time interval for each sample in days.  File name format is INP_Concentrations_StorageProtocol_TreatmentType.  For example, INP_Concentrations_-20C_Heated contains cumulative INP spectra for all heat-treated samples stored at -20 C.  

	2. Frozen_Well_Counts: Contains frozen and unfrozen well counts, corrected for freezing events in instrumental control sample (ultrapure water dispensed from Sartorius arium(R) Pro) within 2 C temperature bins between -5 and -19 C and storage time interval (days).  File name format is Frozen_Well_Counts_StorageProtocol_TreatmentType.  For example, Frozen_Well_Counts_Fresh_Untreated contains frozen and unfrozen well counts for all fresh, untreated precipitation samples.  Well counts were used to apply Fisher's Exact Test (p < 0.01) to identify significant changes in INP concentrations in stored samples.  
	
	3. Stored_Fresh_INP_Ratios: Contains stored:fresh INP concentration ratios between -5 and -19 C, binned by 2 C, and storage time interval (days).  File name format is Stored_Fresh_INP_Ratios_StorageProtocol_TreatmentType.

This folder also contains MATLAB analysis scripts for generating all figures featured in the manuscript.  Fresh_Precipitation_Figure.mat generates Fig. 1 and Stored_Fresh_Ratio_Figures.mat generates Figs. 2-4.

The SampleNameKey shows which samples (S01-S16) correspond to which sampling periods, as in Table 1 of the manuscript.

INP concentration data for stored and fresh precipitation samples were obtained using the SIO-Automated Ice Spectrometer (SIO-AIS), as described in:
Beall, C. M., Stokes, M. D., Hill, T. C., DeMott, P. J., DeWald, J. T., and Prather, K. A.: Automation and heat transfer characterization of immersion mode spectroscopy for analysis of ice nucleating particles, Atmos. Meas. Tech., 10, 2613–2626, doi:10.5194/amt-10-2613-2017, 2017.