What is US-ITASE 2? The US-ITASE 2 program is a platform for multiple scientific research projects that focus on spatial variations across the East Antarctic Ice Sheet between Taylor Dome and the South Pole. The project is part of the US contribution to the International Polar Year. Links: (IPY Website) http://www.nsf.gov/od/opp/ipy/ipy_awards_0607.jsp (List of NSF funded IPY Projects)
The primary goal of the 2 field expeditions is to determine the spatial variability of the last 200 years across the ice sheet and to compare this record with the findings of the previous US-ITASE program in West Antarctica. In cooperation with the rest of ITASE, US-ITASE aims to contribute to how we understand ocean-ice sheet climate interactions, climate variabililty, and human impact on climate over the last 200 years. The US-ITASE heavy-traverse platform offers capabilities similar to a large ocean-going research vessel with logistic and scientific support for numerous researchers while traveling long distances (1000+ km) with limited limited intermediate support. (From the US-ITASE Executive Summary submitted to NSF):
Complete US-ITASE
Science & Implementation Plan (from the University of Maine) US-ITASE 2 Route Over two years we will traversed from Taylor Dome to South Pole along a corridor behind the Trans-Antarctic Mountains, passing through the upper reaches of the major East Antarctic Ice Sheet glaciers that drain into the Ross Ice Shelf. The actual route was be modified as we encounted crevasses that were not detected by preliminary satellite image analysis, or discovered features of scientific interest. We also colleted radar data and ice cores from a number of short (100-200 km) traverses oriented perpendicular to the main traverse route. These profiles provided the opportunity to collect data along ice flow lines.
Results, Publications & Data Results of the project will be posted here soon after the first field season. As we publish our findings we will post relevant data sets at the National Snow & Ice Data Center. US-ITASE 2006: The traverse route started at Taylor Dome near the Transantarctic Mts. just west of McMurdo Station. The route headed inland and then turned south 130 km from Taylor Dome. We continued south into the Byrd Glacier drainage, collecting ice cores at four sites as well as over 500 km of deep (3 MHz) and shallow (400 MHz) radar data. Logistical problems limited our travel distance this year, but we still made good progress and expect to make it to South Pole in 2007. -Route map
-Deep radar profile (3 MHz) from upper Skelton Gl. drainage, 50 km west of Taylor Dome. Processing includes bandpass filter, NMO, and TK migration.
-Comparison of 400 MHz crevasse-detecting radar results with shallow reflectors seen in low-gain channel of 3 MHz data collected in upper Byrd Gl. drainage.
US-ITASE 2007: Instrumentation & Methods We operate a 3 MHz radio echo-sounding system to transmit and receive radio waves through as much as 3.5 km of ice. This signal frequency translates to a wavelength of about 56 m in ice. The transmitter (made by the Kentech) emits pulses at frequency of up to 2 kHz. The pulses are emitted by our transmitter antenna, a 40 m dipole dragged along the snow surface. 135 m in front of the transmitter is an identical dipole antenna that receives the signal. The signal is amplified and passed on to an oscilloscope board mounted directly on a field-ready PC computer. The scope board identifies the incoming signal, digitizes it, and sends it to the computer to be stored on the hard drive. The scope board is extremely fast, sampling the signal at up to 200 million samples/second. Each sample of the signal is digitized to a 14-bit value and stored on the computer along with the recording parameters and a precise time-stamp. We use the scope board's speed to stack the incoming signal to remove much of the environmental radio noise that hides our reflected signal. We stack the data in the field by averaging about a thousand of the transmitter pulses and their resultant echoes from the bedrock and internal layers. The traverse train travels at about 12 km/hr so we generally stack 1200-1500 pulses in order to record a trace every few meters. Stacking and the fast scope board allow us record a dense profile of traces while eliminating much of the noise that would make the data difficult to process and interpret. Field Logistics Our radar system operates primarily during the traverses between ice coring sites. The system and operator are towed as the very last sleds in the traverse train to eliminate radio noise from other instrumentation or reflections from the metal sleds and equipment. The receiver and operator are housed in a small shelter built on a wooden Komatik sled. The shelter protects the computer and operator from wind, cold, and snow. Power for the receiver can be derived from a solar-powered battery system, or a small gasoline-powered generator mounted on the back of the sled. Batteries to power the transmitter are charged by the solar panels or the generator. The shelter is also equipped with a GPS receiver to geolocate the radar data. A survival bag is strapped to the front of the shelter in case of emergency. The transmitter is towed 135 m or more behind the receiver sled. The transmitter and its battery sit in a small sled and are protected from the elements by the sled's nylon cover. The antennas for the transmitter and receiver are housed in strong hydraulic hoses and tied to the tow ropes to keep the antennas as straight and parallel as possible.
US-ITASE 2 corridor Over two years we traversed from Taylor Dome to South Pole along a corridor behind the Trans-Antarctic Mountains, passing through the upper reaches of the major East Antarctic Ice Sheet glaciers that drain into the Ross Ice Shelf. The actual route was modified as we encountered crevasses that were not detected by preliminary satellite image analysis, or discovered features of scientific interest. We collected radar data and ice cores from a number of short (100-200 km) traverses oriented perpendicular to the main traverse route. These profiles provided the opportunity to collect data along ice flow lines.
The traverse route started at Taylor Dome near the Transantarctic Mts. just west of McMurdo Station. The route headed inland and then turned south 130 km from Taylor Dome. We continued south into the Byrd Glacier drainage, collecting ice cores at four sites as well as over 500 km of deep (3 MHz) and shallow (400 MHz) radar data. Click on the map for a larger image or open full-resolution
 
2007-08 Field season We started the traverse at site 06-4 in the upper Byrd Glacier drainage basin where we left the tractors and sleds at the end of the 2006-07 season. The traverse left the winter-over site on Nov. 15, 2007 and traveled 1,200 km to the South Pole where we arrived on Dec. 24, 2007. Ice cores were collected at four sites, including Titan Dome. We collected nearly 1,400 km of 3 MHz radar data along the route and local profiles at the ice core sites. We found ice over 3 km thick in places, very complicated ice stratigraphy, and evidence of a few subglacial lakes. Click on the map for a larger image 
Related Sites Itase Log at University of Maine Itase Website at University of Maine Contact Information
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