Catherine Cahill - US grants

This award is to continue an REU site program at the Geophysical Institute of the University of Alaska. Building on success since 1987, this program will give further research opportunities to undergraduates majoring in the physical sciences. The program objective is to acquaint undergraduates with life and work at a research institute. The objective is achieved by providing summer educational work opportunities in which undergraduates become interns participating in the research activities at the Institute. Research topics concentrate on space physics and aeronomy, but also extend to atmospheric science, and in a minor way to solid state physics and laser physics. Students are assigned to conduct research with individual principal investigators who direct their work and serve as mentors during their internship. A common program of weekly lectures and field trips is designed to expose interns to fields of research beyond the scope of their project. Through their close relationships with their mentors, contacts with graduate students, attendance at seminars, lectures, and thesis defenses, and participation in field trips, the interns gain a first hand perspective on life and work as a research scientist.

In the framework of the Variability of the American Monsoon Systems (VAMOS) Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-REx), this project will study the changes in the microphysical characteristics of the Stratocumulus (Sc) cloud layer off the coast of Chile in the Southeast Pacific, which is under the influence of polluted continental air. A complete set of tropospheric aerosol instruments at the land-ocean boundary will be deployed at the remote village of Paposo in Chile during October 2008. This exploratory research aims to connect the in-situ chemical composition of aerosols, the total column aerosol optical properties, and in situ aerosol microphysical characteristics measured on land with the MBL (Marine Boundary Layer) dynamical structure and the microphysical and structural changes of the Sc layer during the interaction of the Sc with the polluted air flowing off the coast. A suite of measurements will be made to determine how the off-shore continental aerosols are entrained in the MBL, and how microphysical-structural changes induced in the Sc cloud layer can be determined using polarimetric lidar measurements.

This project will explore the capabilities of polarimetric lidar in determining aerosol properties. It must be carried out in October 2008, as it is only during the VOCALS field campaign that the remote field site will be available. Moreover, the value of the measurement attempted under this project will be greatly enhanced by their coincidence with the measurements to be made by other investigators at the field site as well as those made offshore during VOCALS REx.

Broader impacts of this project are in its contributions to the overall VOCALS-REx dataset. The project will provide training for undergraduate students in aerosol physics, environmental chemistry, and optical remote sensing via the Research Experience for Undergraduates and the Arctic Region Supercomputing Center summer internship programs at the University of Alaska Fairbanks.