Impacts of Cruise-Ship Entry Quotas on Visibility and Air Quality in Glacier Bay

Increasing cruise-ship entry quotas in Glacier Bay National Park by 35% marginally impacts air quality and visibility, with minimal changes to haze indices despite shifts in aerosol composition. The study used the Weather Research and Forecasting model coupled with chemistry to simulate scenarios under different ship quotas (2008 baseline vs. increased entries). While sulfur-dioxide concentrations decreased and ammonium-sulfate aerosols increased under higher emissions, visibility remained largely unchanged, except on days with high relative humidity or calm winds. Best and worst visibility days aligned between scenarios, but relative humidity alone governed visibility in the absence of ship emissions. Even small changes require careful consideration for conservation efforts.

Mölders, N., & Gende, S. (2015). Impacts of Cruise-Ship Entry Quotas on Visibility and Air Quality in Glacier Bay. Journal of Environmental Protection, 06(11), 1236–1256. https://doi.org/10.4236/jep.2015.611109