Each winter in the Mount Washington Valley, a visitor arrives at the roof's edge of every home and business. This visitor sometimes gets in our way, but usually watches us from above as we live each day. Its existence is dependent upon the weather conditions that Mother Nature provides. It can span meters long and have a sharp edge, or grow to become short and stubby with wide length. This visitor, the icicle, is one of the most recognized symbols of winter. Despite being silent in its manner, the icicle's formation and dynamics consists of great intricacy.
Believe it or not, there is a science as to how and why icicles develop. Icicles are often misunderstood not only for their beauty, but also the importance of their formation. The most basic definition to describe an icicle is that it is formed due to the freezing of dripping water or melting snow. Given this reasoning, the icicle forms into the shape of a cone or spike. It is important to note that icicles are not confined to the roofs of our homes and businesses, but that they also hang from trees, waterfalls, fences, and utility poles.
The birth of an icicle commonly occurs when the temperature of air and snow rises above 32 degrees, otherwise being the melting point. When the snowmelt flows downward on an object, it begins to engage itself into a war between gravity (downward force) and surface tension (flat flow). Ultimately, the war will lead to positive results of evenly spaced liquid ripples. When the temperature drops below the melting point, the ripples will freeze and become the base root for the developing icicle. This same process repeats itself multiple times, which results in progressive layers for the icicle.
After a period of time, the icicle begins to develop horizontal features. Rings expand around the icicle where they eventually encircle it towards the tip. These rings are very fragile when they first develop. However, the water from the snowmelt rapidly solidifies them. The water also adds layers to the forming icicle, which in turn helps it to grow. Mother Nature is in control as to how many times such a process will repeat itself, but even after active growth is finished, the icicle will continue to reshape and define its look.
It is not uncommon for an icicle to contain bubbles or produce a milky appearance after its developmental stage. Icicles have also been known to grow meters in length, but melting and gravity causes them to fall towards the ground prematurely. Icicles usually collapse during significant winter storms that produce high wind and heavy snowfall. People have been seriously injured during such times because of the capacity ice has had on the human body. Despite any negative aspects that icicles may produce, they represent a world of beauty that have captivated generations here in North Conway.