Glaciers have always fascinated me and I've planned many a trip and hike to see glaciers and the landscapes they have formed. As we moved further north along the coast of Baffin Island, we were treated to the sight of many glaciers.

    GlacierA mass of ice that persists for many years and notably deforms and flows under the influence of gravity. Primer

    Here is a quick introduction into glaciers.

    Glacial Formation

    Here is an explanation of how glaciers form. It was included in the "Flakes, Blobs, and Bubbles" Lesson created by Polar Educators International for Polar Week held in September 2012.

    "Glaciers and ice sheets form as snow accumulates. As overlying snow accumulates, the pressure increases, weighing down the underlying snow. This creates a layer of dense snow, called firn. Eventually the firn gets further compacted and develops into solid ice. As the process occurs, air between the snow grains gets trapped. This air, once preserved in the ice, can be sampled to learn about the composition of past atmospheres. Scientists, who study ice cores, use these trapped-gases to understand how concentrations of greenhouse gases like CO2 and CH4 (methane) have varied over time." (Authors: Dan Zwartz and Heidi Roop, Antarctic Research Centre, Victoria University of Wellington, New Zealand) You can learn more about ice core drilling at the West Antarctic Ice Sheet by reading Heidi Roop's Blog.

    Snow, Firn, Ice
    Creating a glacier

    Glacial Definitions

    • Moraines - As a glacier moves it carries debris along with it. A moraine is that material usually made up of rocks, boulders, sand and silt.

    • Terminal Moraine - Debris left at the bottom end of the glacier

    • Lateral Moraine - Debris deposited along the sides of the glacier

    • Medial Moraine - Debris deposited between glaciers coming from two different valleys as they merge into one

    • Glacial Till - Debris that consists of a great deal of unsorted smaller rocks and gravel

    Buchan Gulf and Icy Inlet Hike - Day 6 August 16, 2013

    Here are some photos from our Day in Buchan Gulf and Icy Inlet. We were treated to many glaciers and a hike in Icy Inlet where we could see meltwater from a glacier and the glacial moraines.

    Glacial Front
    Glacier feeding into ocean from Baffin Island

    Lateral Moraine
    Glacier with some lateral moraine

    Terminal Moraine
    Glacier showing terminal moraine

    Meltwater and Till
    Glacial meltwater and till

    Water and Glaciers

    Freshwater comprises only 3% of the water on the Earth. Mountain glaciers are an important source of fresh water across the globe. These glaciers are often referred to as the Third Polar Region in the world. Icecaps and glaciers make up 68.7% of the freshwater on the Earth. As the global temperature increases many of the mountain glaciers are melting at an increasing rate threatening the security of this water supply. The Greenland and Antarctic ice sheets are also changing. Glacial ice that feeds into the ocean has the potential to increase sea levels.

    Earth's Water
    Distribuition of Earth's Water Source: Gleick, P. H., 1996: Water resources. In Encyclopedia of Climate and Weather, ed. by S. H. Schneider, Oxford University Press, New York, vol. 2, pp.817-823.

    Greenland Visitor: An Ice Island from Petermann GlacierA mass of ice that persists for many years and notably deforms and flows under the influence of gravity. - Day 5 August 15, 2013

    The ship passed by a 3.7-kilometer-long ice island currently anchored in the water off of Cape Raper on the afternoon of August 15, 2013. This ice island was created from a calving event on July 16, 2012 of the Petermann GlacierA mass of ice that persists for many years and notably deforms and flows under the influence of gravity. in Greenland. Here are a couple of satellite images of the event.

    NASA Earth Observatory Image
    The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite captured this image of Ice Island on July 17, 2012

    MODIS Image of 2012 Calving Event
    Modis Image of Ice Island from Petermann Glacier

    Here is a map that shows an estimated path for the journey of the ice island. It has traveled approximately 750 nautical miles since it left Petermann GlacierA mass of ice that persists for many years and notably deforms and flows under the influence of gravity. July 16, 2012 to create the Ice Island we saw off of Cape Raper in Baffin Island on 8-15-13.

    Ice Island Journey
    Approximate Distance Ice Island traveled to current location

    Dark blue streaks seen in the ice are intrusions, similar to geologic intrusions in a rock. The melt streams on the surface of the ice island refreeze into a dense, bubble-free ice.

    Up Close
    Ice island up close, created from calving of Petermann Glacier in 2012

    Ice Island
    Ice island created from calving of Petermann Glacier in 2012

    Greenland Mega-Canyon Discovered

    A recent story in the news talked about the discovery of a mega-canyon underneath the Greenland ice sheet. It extends for 460 miles and the mouth of the canyon lies under the Petermann GlacierA mass of ice that persists for many years and notably deforms and flows under the influence of gravity. where it meets the sea. It is about twice the length of the Grand Canyon, twice as wide in most places, but only half as deep. Like the Grand Canyon it appears to be formed by a river long before an ice sheet existed in Greenland. Scientist, Jonathan Bamber from the University of Bristol, discovered this canyon by analyzing an incredible amount of data collected by research airplanes that have been flying over Greenland for the past 40 years.

    Image of enormous canyon below the ice sheet in Greenland. Courtesy of J. Bamber/University of Bristol

    http://youtu.be/ENg9Hci9y3M

    Date
    Weather Summary
    Partly cloudy
    Temperature
    42

    Comments