Development of heterogeneous ice nucleation rate coefficient parameterizations from ambient measurements

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Ice nucleating particles (INPs) are a rare subset of particles that can have an outsized impact relative to their prevalence. To simulate INP variability, models require parameterizations for the most important sources of INPs.  Most parameterizations in the literature were developed from laboratory experiments that used proxies for ambient particles. Whether these laboratory models effectively represent ambient aerosol is still not well understood and parameterizations developed from field measurements may be more atmospherically relevant. Expanding on previous work in which we used an ice chamber and an single particle mass spectrometer (SPMS) to characterize INP composition, we use the combined measurements to calculate heterogeneous ice nucleation rate coefficients for ambient particles. We find good agreement between our results for dust and sea spray aerosol with previous results.  We also determine the relative contribution of each measurement to the total measurement uncertainty using a Monte Carlo approach and find that the biggest source of uncertainty is the sampling efficiency of the SPMS.