Research Objectives

One of the remaining outstanding questions in atmospheric ice initiation is the nature of the particles on which ice form (ice nucleating aerosol particles or ice nuclei, IN).  The primary goal of this project was to demonstrate methods to improve the current limited understanding of the chemical nature of atmospheric ice nuclei. Significant advances in this regard were made through the combination of two unique, state-of-the-science instruments. The specific objectives of the proposed work were as follows:

1. Deploy an instrumental system combining a continuous flow diffusion chamber (CFDC) for measuring ice nuclei activation and a single-particle mass spectrometer (PALMS) for measuring ice nuclei composition to sample free-tropospheric aerosols from a high altitude site (Storm Peak Laboratory);

2. Characterize the composition of atmospheric ice nuclei at Storm Peak, processed for conditions present in the upper troposphere, and distinguish the characteristics of these particles from the total aerosol population;

3. Determine the conditions necessary for activating natural heterogeneous versus homogeneous ice nuclei at cirrus temperatures and attempt to distinguish these populations chemically.

4. Use the results of this work to assess the feasibility of developing a combined CFDC/PALMS system for other field missions, possibly from an aircraft platform.

Back to Single-particle Mass Spectroscopy of Ice Nucleating Particles - November 2001