Glaciers and Climate Change
“Are glaciers melting at alarming rates?” “Is climate change really happening?” I have been asked these questions by people and students outside the environmental field. Changes in glaciers seem to be the gold standard for measuring climate change. However, living in the Caribbean, to me glaciers seem like a distant world.
A recent vacation to Alaska on a cruise ship provided me some insight on climate change and its consequences. While in Juneau I visited Mendenhall Glacier and could notice the retreating of this glacier upon my hike in the adjoining rain forest. An old building deep inside the forest revealed the former visitor’s center more than 10 miles from the glacier’s current location as well as a stone marking from 1916 of the ice limit.
Managed by the U.S. Forest Service and part of the Tongass National Forest (the nation’s largest forest), Mendenhall, which is 12 miles long, has been rapidly retreating since 1750. From 1951–1958, the glacier, which flows into suburban Juneau, has retreated 1,900 feet (580 m). The glacier has also receded 1.75 miles (2.82 km) since 1958, when Mendenhall Lake was created. In 2004 the glacier retreated 600 feet and in 2007 another 500 ft..
Glaciers form in areas with large amounts of rain and extremely low temperatures. When snow accumulates, it compacts underlying snow layers from previous years into solid ice. Glaciers cover 10% of our world’s total area. This is the same amount of land used worldwide for agriculture. Glacier and polar ice store more water than all the world’s lakes, rivers and the atmosphere combined. When they melt, sea level rises thus consequences for coastal communities and islands are serious. Rising sea levels inundate wetlands and other low-lying lands In Juneau, I could not help noticing that the Gastineau Channel turns into a wetland at some point during the day. There was a low tide early in the morning. Our forest interpreter told us it is becoming increasingly unavigable as there has been a marked increase in silt build up. Some research into this showed that it has been argued that this a consequence of melting and retreating of Mendenhall Glacier. If current trends continue, it is possible the channel may be entirely blocked and filled with dry land.
Yes indeed, climate change is happening and it is tangible. EPA is working on many programs geared to reduce the harmful effects on human health and the environment of green house gases. While most are voluntary, states and industries are actively engaged. I invite you to take a closer look at your daily activities and try to cut down on your carbon footprint.
About the author: Brenda Reyes Tomassini joined EPA in 2002. She is a public affairs specialist in the San Juan, Puerto Rico office and also handles community relations for the Caribbean Environmental Protection Division.
Editor's Note: The opinions expressed in Greenversations are those of the author. They do not reflect EPA policy, endorsement, or action, and EPA does not verify the accuracy or science of the contents of the blog.