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Analysis of Glacial Melting in Glacier National Park, Montana

Midshipman 1/C Meaghan Allen & Midshipman 1/C Jeena Bermudez, General Science 2021

Advisor: Professor Peter Guth, Oceanography Department

Abstract Results and Discussion Satellite imagery of Glacier National Park in Montana In our analysis of the glaciers in Glacier National Park, we see a large displays the environmental effects this area is facing, such as decrease in the area of glaciers. The blue outlines are glacier boundaries erosion and melting. Glacier National Park entails 25 active collected in 1966. The red outlines are glacier boundaries collected in glaciers today. Sentinel-2 (or Landsat) satellite imagery 2015. Table 1.1 Shows the difference in area in units of square meters. shows environmental change in Harrison Glacier, Old Sun The largest change in the glaciers we observed was a 71.2% decrease in Glacier, Pumpelly Glacier, Rainbow Glacier, Chaney Glacier, area of Shepard Glacier. The smallest glacier change we observed was a and Shepard Glacier from year to year. While even the large 10.3% decrease in Pumpelly glacier. This is especially significant due to reduction in glacial area is distinct even to the naked eye, the the fact that it is one of the largest glaciers in GNP. With such Normalized-Difference Snow Index (NDSI) shows that the significant melting in a glacier this size, it is no surprise that smaller edges of even the largest glaciers have melted within the past glaciers have melted so much. Glacier national park has experienced an 30 years. increase in the average temperature and continuous increase of temperatures can be expected. If these trends continue this could mean an average of 200 square meters of area loss a year. After examining the Figure 1. Glacier National Park in Montana Figure 2. Glacier Locations (red) within Background Glacier National Park NDSI difference maps, we noticed that the majority of change in NDSI Glacier National Park (GNP) is a huge tourist attraction in the occurs along the edges of the glacier boundaries. The majority of upper Northwest side of Montana with many glaciers melting occurs within the elevation range of 2000 and 2600 meters. including Harrison Glacier, Old Sun Glacier, Pumpelly Because of the way that National Parks are protected, they incur Glacier, Chaney Glacier, Shepard Glacier, and Rainbow minimal environmental change aside from the change happening on a Glacier. Over time, many of the glaciers that have been the global scale. GNP’s glaciers serve as a controlled microcosm of glacier main attraction of this tourist site have melted away. Due to change around the world.. factors such as global warming, glaciers all over the world have been melting. The temperature of the Earth’s surface has increased approximately 1.5 degrees fahrenheit in the past Conclusion 100 years. The rate of warming in northwest Montana is Glacier melting has significant impact on the ecosystem. Glaciers approximately twice that of the average on Earth. The provide fresh water to mountain areas, without with wildlife could increase in temperature has caused many of the park’s struggle to survive. Significant increases in glacial melting can be glaciers to melt and even increases the chances of wildfires partially attributed to rising global temperatures as well as decreased happening. With area damage, history is also lost as the cloud coverage, and variation from standard precipitation. The trend of glacial melting in Glacier National Park that has been depicted in these attraction also holds deep rooted history. Researchers have Figure 3. Boundaries of Harrison Glacier in 1966 figures is a small example of glacial melting globally. discovered that European explorers and several different (blue) and 2015 (red crosshatch) Figure 4. Boundaries of Rainbow Glacier in 1966 tribes had explored and even settled in this area. (blue) and 2015 (red crosshatch) Acknowledgments We would like to thank Professor Peter Guth, without whom we would not have been able to complete this project. His love of geology and Data and Methods wildlife inspired us and lifted our spirits in the worst of times. Using the Glacier Database data given from GLMIS for Western Canada and the United States, we inputted the data into MICRODEM and merged our KMZ file from Google Earth(shown in red in figure 2). Using USGS glacier boundary data from 1966 until 2015 to pinpoint the glaciers we would examine , we assessed recent glacial melting. We merged the boundary data sets and layered them on top of elevation data from USGS. We then examined the difference in glacier area and melting over the years due to various factors such as global climate variation. We also examined Landsat data from 1991 and 2011 and found the Normalized Figure5. Boundaries of Pumpelly Glacier in 1966 Difference Snow Index (NDSI). We created a difference map References (blue) and 2015 (red crosshatch) Figure 6. Boundaries of Old Sun Glacier in 1966 determine where albedo decreased. (blue) and 2015 (red crosshatch) Area of the Named Glaciers of Glacier National Park (GNP) and Flathead National Forest (FNF) including Little Ice Age extent, and years 1966, 1998, 2005 and 2015. (n.d.). Retrieved November 09, 2020, from https://www.usgs.gov/data-tools/area-named-glaciers-glacier-national-park-gnp-and-flathead-n ational-forest-fnf-including Table 1. Differential Graph of Glacier Area from 1966 to 2015 in Glacier National Park

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Figure 7. Boundaries of Shepard Glacier in 1966 (blue) and 2015 (red crosshatch) Figure 8. Boundaries of Chaney Glacier in 1966 (blue) and 2015 (red crosshatch)