Earthwatch Institute engages people worldwide in scientific field research and education to promote the understanding and action necessary for a sustainable environment.
On the Alaska Glacier research project participants explore geological processes involving surge and outburst events on the largest alpine glacier in North America, Alaska's Bering Glacier, led by Dr. Jay Fleisher (State University of New York, Oneonta) and his experienced field staff.
In Alaska, participants share "weatherport" house tents with teammates on the shore of Lake Vitus, with a view of the calving Bering ice front, icebergs, and the Chugach Range, enjoying occasional showers and the rigors of pit toilets. In both cases, you'll rediscover the simple pleasures of peanut butter and canned tuna and share cooking of nonperishable delights over camp stoves.
These are extraordinary times at Bering Glacier, Alaska. Unlike any other glacier in Alaska, the Bering possesses two rather unique characteristics. It is known to be affected by a 25-30 year surge cycle that is accompanied by outburst floods. Floodwater is discharges through a peripheral drainage system along which rapid sedimentological changes are part of the normal regime (Fleisher, et al, 1998; Fleisher, et al., 1995; Lingle, et al., 1993; Molnia, 1993; Muller, et al., 1993; Post, 1972). Working with a unique pre-surge frame of reference, we assess the impact of the 1993-95 surge and outburst floods on ice-marginal environments and foreland terrain (Fleisher, et al., 2004).
The glacier has rapidly retreated during the ten years following the surge (1995-2004), thus exposing its erosional effects on overridden terrain. Field work during the past three field seasons has yielded astounding preliminary results. It appears that the dynamic erosional effects of overriding ice on an outwash foreland are secondary to changes caused by pressured subglacial water movement through basal conduits (Fleisher, et al., 2003). In addition, a database of field measurements, aerial photos, and satellite imagery spanning the past surge cycle permits an assessment of Global Warming on current rates of downwasting and retreat.
During the 2006 field season, we will deal with a diverse assemblage of topics, including:
- Measurement of ice front retreat and surface melting
- GPS mapping of ice front position and foreland terrain
- Measure daily rates of glacier surface melting and evaluate factors that control melting
- Measure annual rates of retreat and ice surface lowering
- Consider the influence on Global Warming
- Trace the pathways of englacial water movement in exposed tunnels
- Assess impact of 1993-95 surge on foreland terrain
- Effects of subglacial erosion and deposition by water and ice
- Effects of outburst events on ice-marginal foreland
- Effects of hydrofracturing
- Conduct topographic surveys
- Establish bench marks elevations for construction of topographic map
- Construct topographic profiles for landform interpretation
- Continue investigation of foreland stratigraphy
- Identify and describe stratigraphic units
- Map, correlate, and interpret pre-history glacial events
- Sample fossil trees for radiaocarbon dating and dendrochronologic correlation
The anthropogenic input of greenhouse gasses through the burning of fossil fuels exacerbates normal trends of climate change that are known to be part of the geologic record. Solutions to this growing problem must be based on the measured effects of warming trends in all ecosystems, with glaciers being one of the most conspicuous examples. The problem is compounded by surge and outburst flood events. Skeidarárjökull in Iceland, an outlet of the Vatnajokull Ice Cap, shares a comparably dynamic history with Bering Glacier. Our long-term goal is to link Bering Glacier research findings with those at Skeidarárjökull, Iceland.