Questions have long been asked about the effects of cruise ships on Skagway’s air quality. The Skagway Traditional Council (STC) decided this would be a good summer to sample the air — without any cruise ships.
The lack of ships this year makes it unique, said Reuben Cash, STC environmental coordinator. It means that the data collected this season will reflect only the community’s contribution to particulate matter in the air, or other sources that blow into town such as forest fire smoke.
“Clean air is essential for health,” said Cash.
The project could be the start of building a framework that monitors air quality index locally. Data collection for the project began in April and will continue until the end of September.
The testing will be conducted using three light laser photometer stations that are scattered from the harbor to near the White Pass & Yukon Railroad train yard. The instruments measure particulate matter (PM), which is a result of combustion from cruise ships, car engines, train exhaust, wood-burning stoves and forest fires. Another contributing factor to PM is a result of high-atmospheric chemical reactions from power plant emissions, which can spread long distances around the world.
Data is recorded in real-time by directing a beam of polarized light into a small chamber through which particles move at a consistent rate. When the beam of light detects particulate matter, it refracts and changes its intensity. Each test is set to run for 24 hours and will calculate the average amount of times it detects PM of less than two and a half microns, which is the amount that can be considered hazardous to health and respiratory functions.
“We were able to detect residual amounts of PM under two and a half microns presumably from wildfire smoke originating in the Siberian Arctic,” Cash said.
The U.S. Environmental Protection Agency (EPA) established the health standards, which is what STC modeled its study on for data comparisons.
Once all the data has been collected it will “be compared to EPA standards, analyzed for patterns and correlations to atmospheric conditions, and reviewed by environmental staff and EPA experts and STC to determine whether further data needs to be collected,” said Cash.
Cash has seen that Skagway experiences inversion events when a layer of warmer air traps pollutants and particulate matter close to the ground where people breathe.
To date, there is no comparable data on the air quality for the town.