Abstract
Simulations from the Weather Research and Forecasting Model, inline coupled with chemistry, were used to examine the fate of particulate matter with diameter of 10 μm or less (PM10) in Glacier Bay, Alaska during the 2008 tourist season. The simulations demonstrated that mesoscale and synoptic scale weather systems affect the residence time of PM10, the magnitude of concentrations, and its transport in and out of Glacier Bay. Strong inversions exceeding 2 K (100 m)-1 cause notable trapping of pollutants from cruise-ship emissions, increasing PM10 concentrations up to 43% compared to days with cruise-ship visits without the presence of an inversion. Inversions occurred locally in Glacier Bay on 42% of the 124-day tourist season with an average lifetime of 9 h. Pollutants occasionally originated from outside the National Park when southerly winds advected pollutants from ship traffic in Icy Strait. Occasionally, orographically forced lifting over the Fairweather Mountains transported pollutants from the Gulf of Alaska into Glacier Bay. While hourly (daily) PM10 concentrations reached ~44 μg·m-3 (22 μg·m-3) in some areas of Glacier Bay, overall seasonal average PM10 concentrations were below 2 μg·m-3. Despite up to two cruise-ship visits per day, Glacier Bay still has pristine air quality. Surface and upper air meteorological state variables were evaluated through an extensive network of surface and radiosonde observations, which demonstrated that the model was able to capture the meteorological conditions well.
Highlights
IntroductionGlacier Bay National Park and Preserve, Alaska (hereafter called Glacier Bay), is one of the most pristine glacial fjord areas in the world, comprising a notable part of the 24.3 million-acre Kluane/Wrangell-St. Elias/Glacier Bay/Tatshenshini-Alsek World Heritage Site, and one of the largest marine protected areas in the northern hemisphere
Glacier Bay National Park and Preserve, Alaska, is one of the most pristine glacial fjord areas in the world, comprising a notable part of the 24.3 million-acre Kluane/Wrangell-St
Surface Observations While Weather Research and Forecasting Model (WRF)/Chem adequately captured the near-surface meteorology throughout the 124-day tourist season, similar to many other high-latitude studies (e.g. [4] [26] [30] [31]), it failed in some instances to capture the atmospheric dynamics when conditions were changing rapidly, or over complex terrain
Summary
Glacier Bay National Park and Preserve, Alaska (hereafter called Glacier Bay), is one of the most pristine glacial fjord areas in the world, comprising a notable part of the 24.3 million-acre Kluane/Wrangell-St. Elias/Glacier Bay/Tatshenshini-Alsek World Heritage Site, and one of the largest marine protected areas in the northern hemisphere. The park includes more than 2.6 million acres of federally designated candidate “wilderness” areas constituting one of the largest, and one of the few marine-based units in the U.S National Wilderness Preservation System. While Glacier Bay is characterized by large areas of marine and terrestrial wilderness, a mandate of all U.S national parks is to provide opportunities for visitation and enjoyment. There are no roads connecting Glacier Bay to outside areas of Alaska, meaning that the park is accessed almost exclusively by marine vessels, including commercial cruise-ships. 225 cruise-ship entries are permitted during the 5-month tourist season (May 15-September 15), constituting over 400,000 (~97% of total) visitors annually
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
