Global warming topic continuesBy JEFF NORTH,
The blast of arctic air we experienced this past weekend was almost therapeutic. Sweaters and jackets were brought from the closets and only a hint of moth balls could be detected in the crisp air. Shorts and sneakers were replaced with jeans and boots. Maples finally began to show a crown of crimson on their upper most branches as the water flow is definitely moving southward allowing those anthocyanins to be revealed until a killing frost stops the show.
Everyone I spoke with was in a grand mood. Conversation was gay and lighthearted. A more perfect weekend could not have been ordered, excluding a couple of football scores from around the state. Of course, I should never have brought this up to cast a dark cloud over a wonderful two days. As my brother-in-law Mr. Charlie says though, if you come to campus on a beautiful fall day for football, you’re coming for the wrong reason. Touche’, brother, you got that right. The chilly air and the north wind stirred my inner soul as well. As a rush of wind and leaves would swirl, I thought of the mountains and valleys to our north. Glacier country was on my mind and the inspiration for another article.
Glaciers are persistent bodies of dense ice that are formed by snow and ice accumulations that exceed the rate of melting. For millions of years these vast creations of arctic precipitation have covered approximately 10 percent of the earth’s surface. Though I have mainly thought of glaciers being only in the Arctic and Antarctica, they are actually present in over 50 countries.
The word “glacier” derives from the Latin word glacies, meaning ice. They are in constant motion and the speed at which they travel is entirely dependent upon the rate of glacial melting and slope of the landscape upon which they rest. Typically, glaciers move at the rate of around three feet per day but some have been documented to move 70 feet per day under conditions where water acts as a lubricant and speed is increased. Conversely, under colder conditions, movement becomes stagnant when water under glaciers freezes thus slowing the process.
Glacial ice is the largest reservoir of freshwater on earth. This water is stored in the form of ice and as temperatures warm in spring and summer, water is released creating a vast resource for plants and animals. Pools form in depressions providing sources of water up and down the corridor in the valleys where glaciers exist. Glacial ice can appear blue. This is because water molecules absorb other colors more efficiently than blue thus reflecting only blue to the human eye. This reminds me of a question posed to me during my defense and orals in graduate school. A large textbook was on the table in the conference room and I was asked by one of my professors what color it was. Knowing full well that he was up to something I replied that it “appeared” to be green. Of course he made me take a stand as to whether it was green or not and I stated yes, it is green. He informed me that indeed it was not green for every color in the spectrum was absorbed by this book except green. So it is with glacier blue, I presume. Another reason glaciers appear blue is the lack of air bubbles. The typical white color of ice is due to abundant air bubbles within and glacial pressure squeezes them out reflecting a more pure blue color.
Glacier bodies vary greatly in size and thickness. Those that are larger than 20,000 square miles are referred to as ice sheets or continental glaciers. Tidewater glaciers are those that terminate at the sea. As they move, pieces break off or calve, forming icebergs. This phenomenon is a huge tourist attraction for those that venture into this country to witness. Caution must be taken however when viewing this act of nature for waves created by the explosion of dropping ice has been known to swamp and capsize boats. Hypothermia will take place in only minutes if you find yourself in these frigid waters.
The global warming debate is ever present and has become politicized in every imaginable way known to man. One of our most accepted ways to measure global warming has been to measure glacial health through a process known as terminus behavior. Healthy glaciers have large accumulation zones by which more ice is accumulated than lost through melting. Following the end of the Little Ice Age around 1850, the stability of glaciers around the globe retreated significantly. There was a documented cooling period between 1950 and 1985 which led to the advance of many alpine glaciers and overall health improved. Since then however, a warming trend has been observed and glacier mass has retreated once again. Is this a true sign of global warming though? Do we experience periods of warming trends that can at times last for centuries? Conversely, does the earth also experience cooling off periods which can last just as long? This debate will continue long after we’re gone from this planet, I assure you. I seem to remember ice crystals protruding from the ground years ago more than I do now. Dad wouldn’t let me take the bird dogs out to the sage fields until the ice melted so they wouldn’t cut the pads on their feet. I don’t see this as much anymore, but on the other hand, my pipes were on the verge of freezing when we endured 8 degree weather this past January. So from these examples, you can see how this debate will continue. Regardless, glaciers are an intriguing part of our planet that helps sustain life. If you can, venture to our north country to experience the glacier in all of her splendor. You’ll be glad you did.
Until next time enjoy our woods and waters and remember, let’s leave it better than we found it.