Glaciers Under Siege
Over many years, snow can compress into large, thick ice masses—glaciers. Glaciers move very slowly over time, carving out the landscape and creating new features. Glaciers have fall lines like rivers where the bed of the glacier narrows and descends rapidly, creating an icefall (like a waterfall). For example, on Mount Everest, the Khumbu Icefall is arguably the most difficult and treacherous terrain. In addition to creating striking and astounding topographies, glaciers are globally important. They currently cover approximately 10% of the total land area on Earth, most located in the Arctic and Antarctic. And glaciers and ice caps contain about 69% of the total freshwater on Earth. If all land ice melted, the sea level would rise about 230 feet (70 meters), causing a domino effect of catastrophic events. And global warming is causing the world’s glaciers to melt rapidly, with glaciers near the Equator especially at risk. Glaciers are not only important as indicators for global warming, but also as a source of freshwater, feeding many rivers around the world. The movement of glaciers has also created, beautiful, dramatic landscapes, like those seen in Glacier National Park (Montana, USA, and British Columbia, Canada). When Glacier National Park was designated in Montana in 1910, there were about 150 glaciers within the park’s borders. Currently, the number of glaciers is estimated to be less than 30. The loss of glacial ice due to rapid melting decreases the amount freshwater available for plants and animals. Scientists are concerned about glaciers of the Swiss Alps (pictured), predicting glaciers of central Switzerland may nearly completely disappear by the end of the 21st century. On Mount Kilimanjaro (Tanzania), scientists estimate snow has melted more than 80% since 1912. Furthermore, many of the glaciers of the Himalayas (Nepal, China, Bhutan, Tibet, India, Pakistan)—if not all—are retreating, and millions of people depend on those glaciers as a source of freshwater. In the United States, a mean of approximately 46 gigatons of ice were lost from Alaskan glaciers every year from 2003 to 2010. From the poles to the equator and most areas in between, ice fields, glaciers, and sea ice are vanishing. The biggest and most quickly melting glaciers in Antarctica may be those of Pine Island Bay—Pine Island glacier and Thwaites glacier. If melted completely, they may lead to a sea-level rise of 11 feet—a global disaster. See here for more on sea level rise. There are many resources on ways to help combat climate change, like the new book The Carbon Code: How You Can Become a Climate Change Hero by Dr. Brett Favaro.
Photo and haiku by: Samantha Oester