Collaborative Research: A Comprehensive Evaluation of the Interactions between Pollution and Hazardous Ice Fog in Interior Alaska

Colorado State University, Fort Collins CO

Investigators

Abstract

This project is part of a broader effort, the Alaskan Layered Pollution and Chemical Analysis (ALPACA) research initiative and will also contribute to the NSF-funded SNAP-TEC (Sustainably Navigating Arctic Pollution through Engaging Communities) project that includes an intensive field campaign planned for the year 2022. The goal of ALPACA is to better understand the chemical processing of air pollution during the cold and dark conditions in the wintertime in the Arctic. The objectives of SNAP-TEC are to improve the understanding of wintertime Arctic outdoor and indoor air pollution to assist in the sustainable development of the Arctic and improve air quality for Arctic peoples. This project will investigate the composition of ice nucleating particles that form ice fog in the atmosphere during the wintertime in Fairbanks Alaska. Persistent, dense ice fog events cause low visibility conditions leading to significant problems in the transportation and aviation sectors. These fog events also are associated with high pollution levels that can cause adverse health impacts. The project includes a 7-week deployment at a supersite in Fairbanks focusing on measurements of aerosols and their ice nucleation properties, both during ice fogs and clear conditions. The goals of the project are to determine the detailed sources and chemical transformations of ice nucleating particles (INPs) in the Arctic boundary layer, determine how they evolve over the course of ice fog episodes and assess whether INPs can modulate ice fog microphysics. The following hypotheses will be tested: (1) organic/inorganic aerosols from residential wood burning contribute to the INP population that facilitates ice fog formation; (2) INP composition captured at the beginning of events is indicative of those that seed ice fog formation; and (3) under similar temperatures and humidity, variation in INP populations affect ice fog microphysics, especially under mixed-phase conditions. The measurements provided through this effort are essential for better understanding the ice fogs in Fairbanks that affect visibility and human health. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.