It’s the glaciers that give the unique beauty and sheer grandeur to the Canadian Rockies as they create all of the scenery, the lakes, the waterfalls, roaring rivers, the stunning rock cliffs, and the beautiful valleys. Banff National Park has numerous large glaciers and icefields, many of which are easily accessed from a short walk and will literally take you toe to toe with a living glacier. As with the majority of mountain glaciers around the world, the glaciers in Banff are retreating.
Glaciers fill the lakes with silt giving them a distinctive green colour as the water contains tiny bits of rocks and minerals called “rock flour” that is in suspension from the grinding of the glacier. Those rock particles refract the green spectrum of the sun’s light to make it appear green.
The Columbia Icefield is located on the boundary of Banff and Jasper National Parks. One of the largest accumulations of ice and snow south of the Arctic Circle. It covers an area of nearly 325 square kilometres, sometimes reaching a depth of 300-360 metres. The continuous accumulation of snow feeds eight major glaciers including the Athabasca, Dome, and Stutfield Glaciers, all visible from the Icefields Parkway. The Columbia Icefield is a true “hydrological apex,” for its meltwater feeds streams and rivers that pour into the Arctic, Atlantic, and Pacific oceans.
Photographic evidence alone provides testimony to this retreat and the trend has become alarming enough that glaciologists have commenced researching the glaciers in the park more thoroughly, and have been analyzing the impact that reduced glacier ice may have on water supplies to streams and rivers.
The largest glaciated areas include the Waputik and Wapta Icefields, which both lie on the Banff-Yoho National Park border. Wapta Icefield covers approximately 80 km2 in area. Outlets of Wapta Icefield on the Banff side of the continental divide include Peyto, Bow, and Vulture Glaciers.
Bow Glacier, above Bow Lake, retreated an estimated 1,100 m between the years 1850 and 1953. Since that period, there has been further retreat which has left a newly formed lake at the terminal moraine. Peyto Glacier has retreated approximately 2,000 m since 1880, and is at risk of disappearing entirely within the next 30 to 40 years.
Glaciers range in size from ice fields, with major outlet glaciers, to glacierets. Small mountain-type glaciers in cirques, niches, and ice aprons are scattered throughout the ranges. Ice-cored moraines and rock glaciers are also common.
What will happen to the rivers if the glaciers melt away? In fact, glacier meltwaters contribute less than 1% of the total annual flow to the Bow River so their overall contribution is small. However, the portion of Bow River water derived from glaciers rises during the summer as snowmelt wanes. During a drought year with reduced snowfall and rain, the relative contribution of glacier meltwater to the Bow River is higher. Without glaciers in the Bow River basin, water supply during drought years would be much more challenging. However, as long as it snows and rains every year, we can expect the river to keep moving. Water flows the entire length of the Bow River from Bow Lake to the Hudson Bay, 623 kilometres, in less than two weeks.
Today, glaciers store nearly 70 % of the world’s fresh water supply in ice that covers about 10% of the worlds land mass. A believe it or not, the mountains of the Canadian Rockies are not as high as the mountains south in the United States. An illusion is created by the peaks wrapped in glaciers and a lower tree line.
For more and larger photos of Glaciers goto The Picture Window